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subzali
09-09-2011, 09:32 AM
No, I'm not putting a V8 in anytime soon :D

But - the PO of my FJ40 always swore up and down that the secondary on the carb never worked. I had a hunch that that was possible, because Martin is able to outrun me on his 34x10.50 LTBs and 4" lift, and my buddy CJ7 Matt can out-pull me on hills on I-70 and he has 3.56 gears in his Jeep.

The carb on my 2F (a '78 carb) has a vacuum-actuated secondary, as opposed to the mechanically actuated secondary on earlier carbs. But before the vacuum can do its part to move the butterfly, the primary has to be open just about 100%, because there is a mechanical stop that has to get out of the way to let the butterfly turn.

I've been doing some tests with a paperclip on the secondary actuator rod and have found that it's not opening. I checked the secondary diaphragm and it's in perfect condition. I replaced it anyway but I'm still not getting the paperclip to slide down the rod, which means the secondary indeed is not opening. As I pondered this last night while I was looking at it, I jammed my accelerator pedal down to the floor and held it there with my star wrench, and went and looked at the linkage on the carb. The lever was just over 50% of its total travel, nowhere near far enough to move the stop so the secondary could open :eek:. I pushed it further with my hand and was able to get it where it needed to be, and then I was able to turn the secondary by hand. Good, the butterfly isn't stuck to the carb. :rolleyes:

I found the culprit (at least I think) to be the bracket that's bolted to the firewall. It's missing some bushings and grommets so the rod is kinda floating in place, which is allowing it to not travel all the way to where it's supposed to. I looked on SOR and the parts I need are: 042-50F, 042-57, and 042-61. 042-50F is discontinued and no longer available, so I'm wondering if anyone could take a picture and/or measurements for me so I can figure out what it is and how I can duplicate it. Thanks! :cheers:

I would like to have more power :thumb:

subzali
09-09-2011, 12:09 PM
Well after doing a little MUDsearch I found some pictures of what it's supposed to look like. I think mine is wallowed out to the point where it's going to need some :weld: repair before continuing on...
http://forum.ih8mud.com/attachment.php?attachmentid=174355&stc=1&d=1190248391

http://forum.ih8mud.com/attachment.php?attachmentid=152748&stc=1&d=1182529836

http://forum.ih8mud.com/attachment.php?attachmentid=161932&stc=1&d=1185820413

L43dean
09-09-2011, 03:24 PM
So 042-50f is rubber and 042-57 is a metal bushing? Ace Hdw and Napa have several sizes of rubber grommets. Maybe one will be right. I have also bought metal and nylon bushings at Ace. The Ace around here,Iliff and Chambers, is well stocked. The one at 6th and Peoria is very good and been around a long time, lot's of OLD hard to find stuff. Good luck!!!

RicardoJM
09-09-2011, 03:28 PM
It appears there are different part numbers, but might you be able to get the parts from a 60 series in the junk yard?

wesintl
09-09-2011, 03:33 PM
I found more power in my 80 recently..

I unhooked the popup :)

subzali
09-09-2011, 04:00 PM
It appears there are different part numbers, but might you be able to get the parts from a 60 series in the junk yard?

That's actually a really good idea Ricardo, and yes that part is used on the 60 series. Now I just have to figure out when I'll be making a run to the parts yard...

nakman
09-09-2011, 04:48 PM
...Martin is able to outrun me on his 34x10.50 LTBs and 4" lift...

Dude, Martin's got the fastest stock engine 40 I know of.. he has outrun my 80 going up Floyd Hill.. maybe it's those lightweight body panels? I dunno, I think he just knows how to tune that thing. :bowdown:

subzali
09-09-2011, 07:16 PM
It appears there are different part numbers, but might you be able to get the parts from a 60 series in the junk yard?

So I learned more about this system today, and it turns out I already have those bushings and pin spacers. I'm only missing the grommet and need to fix my wallered out hole :(

I'm excited to open the possibility of having an operational secondary circuit on my carb though! :D

L43dean
09-10-2011, 11:18 AM
Hello Matt, Guess what I just found in the parts pile I recently adopted? Thats right, assembly #60 in post number 1. It is the part in the third photo of post number 2, off of Mud I gather. Good day eh?

subzali
09-11-2011, 04:53 PM
Dean, if you could save that for me for a few more days I'll pick it up from you after work this week after work

L43dean
09-11-2011, 09:40 PM
Dean, if you could save that for me for a few more days I'll pick it up from you after work this week after work

you got it!

subzali
09-15-2011, 10:09 PM
It worked!

Thanks to Dean, I was able to procure a replacement firewall bracket. I swapped it out tonight, then went for a drive. The pedal feel totally changed, and now I could feel the break where there's more resistance and I'm getting into the secondary. I could feel a quicker acceleration, and it didn't run out of wind at about 3000 rpm, it just kept pulling. After jumping on the highway and going up an exit, I pulled over and popped the hood. The paper clip on the secondary actuator shaft had moved! For the first time ever since I have owned this 40! Why didn't I discover this sooner!?

So I took it down to Ricardo's test track, aka Surrey Ridge. I hit the bottom of Surrey Ridge at 3000 rpm (about 65 mph), and once I was on the incline I floored it. Fairly quickly the rpm crept up to just under 3500 rpm (about 76 mph), then slowly bled off on the upper portion, getting down to about 3250 rpm (about 71 mph) before the road leveled off again. Since my speedo is broken that's the best I could get for now. I did those calcs based on 30" tires, since my 31x10.50 MT/Rs are worn and I'm not sure what diameter they started life with.

Not a huge difference, but I have more available power than ever before, and it certainly pulled that hill better than it ever has! I can't wait for the I-70 hillclimb next weekend on the way to the Argentine Cleanup!

Now, I wonder how many 2Fs have been ditched for V8s because of a similar problem?

RicardoJM
09-16-2011, 07:59 AM
Most excellent Matt. :D

SteveH
09-16-2011, 09:38 AM
Matt - I used a paperclip on the secondary actuator when I rebuilt the carb on my '78, back in, um, 1991. I have a kit, and you may have given me the inspiration to rebuild the carb again - or at least do the paperclip test - and then do a rebuild. I wish there were a more robust way to test a 2F carb secondary, but I've never found one.

Thanks for posting your results!

Jacket
09-16-2011, 09:53 AM
I'll race ya! :p:

subzali
09-16-2011, 10:19 AM
Matt - I used a paperclip on the secondary actuator when I rebuilt the carb on my '78, back in, um, 1991. I have a kit, and you may have given me the inspiration to rebuild the carb again - or at least do the paperclip test - and then do a rebuild. I wish there were a more robust way to test a 2F carb secondary, but I've never found one.

Thanks for posting your results!

If it works, it works :)

The first problem for me was getting the primary to travel far enough to move the stop so the secondary would be allowed to turn. I was able to determine that with the engine off, by hand. Once I got that figured out, the rest fell into place.

I'll race ya! :p:

You're on! Ricardo and Martin, you better watch out too! :p:

AHorseThief
09-16-2011, 10:54 AM
You're on! Ricardo and Martin, you better watch out too! :p:

FJ40 drag races. Maybe we can get some sponsors and head up to Banimere. I'm sure tons of people would pay to see that. :lmao:

art hog
09-16-2011, 11:39 AM
FJ40 drag races. Maybe we can get some sponsors and head up to Banimere. I'm sure tons of people would pay to see that. :lmao:

A new event for the rally. DRAG RACES!!!!!! 4 wheel burn out contest. smokem if you can.

Uncle Ben
09-16-2011, 11:54 AM
A new event for the rally. DRAG RACES!!!!!! 4 wheel burn out contest. smokem if you can.

I've got the smallest motor in my 40 than anyone...can I play? :D Mines even just a 1 barrel and an auto to boot!

subzali
09-16-2011, 01:36 PM
sure :D

DanS
09-16-2011, 02:44 PM
Can a 4 cylinder play?

subzali
09-16-2011, 03:12 PM
Sure, I'd like to see the smoke that you and Barry can come up with :D

SteveH
09-16-2011, 06:21 PM
I cut 13 seconds off my FJ40's 0-60 time by installing a new 2F, years ago. I dropped from 39 to 26 seconds! Not many people can boast that they shaved 13 seconds off their 0-60.

Rezarf
09-17-2011, 10:09 AM
Now, I wonder how many 2Fs have been ditched for V8s because of a similar problem?

Tell me more of the paper clip trip. Can't I just have someone stomp on it and see if the secondaries are opening?

You have peeked my interest.

Rezarf
09-17-2011, 10:11 AM
I've got the smallest motor in my 40 than anyone...can I play? :D Mines even just a 1 barrel and an auto to boot!

I cut 13 seconds off my FJ40's 0-60 time by installing a new 2F, years ago. I dropped from 39 to 26 seconds! Not many people can boast that they shaved 13 seconds off their 0-60.

Now thats funny! :D My money is on wild rice.

subzali
09-17-2011, 10:17 AM
Drew, the secondary will only open when the primary is basically wide open, and it's vacuum-actuated. The actuation rod for the vacuum is on the front of the carb. You can take a paper clip and put it on that rod. Slide it up against the vacuum chamber, and if after driving around spiritedly you find that the paper clip has been pushed down about an inch then you will know that your secondary is opening.

PhatFJ
09-17-2011, 01:40 PM
1975 FJ-40


Hey Matt, thanks for this great thread!! I am trying to learn the STOCK carb setup as well and this got me to go out and check my setup. I verified all the linkages and vacuum lines, put the paper clip on the front diaphragm linkage and took it for a drive, not only did it NOT move but the motor seems to decelerate when I floor it. So, I pulled the vacuum assembly and verified that it does work, blew into the port feeding the vacuum module and could hear it blowing into the carb body which I can only assume, this is where the vacuum is being drawn from (funny, my emission control repair manual does not even mention this module nor the secondary acceleration). I am at a loss as to why the secondary is not opening, everything seems to be correct. I had Kim push the throttle to the floor while I verified that the linkage IS free to move and open the secondary venturi, could it be that I am not drawing enough vacuum to open it? if so, why? it seems to drive just fine as long as I am not asking for full throttle..



One other thing, while checking the vacuum lines I pulled the throttle positioner diaphragm line and pulled vacuum on it, it does move but it does not hold vacuum at all with the linkages returning to their normal position almost immediately after drawing vacuum, again, my manual does not go into the operation of this unit only the complete circuit, is this supposed to hold vacuum and keep the linkage in position as long as vacuum is being applied?

as always, thanks for the help!!! :thumb:

Brian

subzali
09-17-2011, 04:49 PM
Wow, lots of questions Brian! First let me catch up with some more photos and then I'll try to address your questions as best as I have been able to find out.

First, these pictures show my old bracket, as removed, and Dean's new bracket installed. My old bracket has a clip that holds the speedo cable, Dean's doesn't, so I might still repair my old bracket and re-install it. I think this is because in some years (like '76) the speedo cable doesn't go straight to the t-case; it first goes to a secondary speedo that controls things like the EGR maintenance warning light.

subzali
09-17-2011, 04:51 PM
These pictures show the secondary diaphragm housing and actuating rod on the front of the carb. Snap the paper clip on the actuating rod like so, slide it up like so and if it actuates it will end up an inch or so down the rod :D

(disregard my disconnected vacuum line - I did that for picture clarity and reconnected it after the picture was taken)

subzali
09-17-2011, 04:55 PM
These pictures show the lever attached to the primary butterfly. In the first picture, it's at rest (idle). In the second picture, this is about how far it was getting before I replaced my bracket on the firewall. Clearly the primary wasn't fully open and the secondary wasn't engaging. The third picture shows its correct position when the pedal is on the floor (after new bracket is installed) and the secondary is allowed to open. (it's the brightly illuminated lever near the bottom of the carb with the hole near the end).

subzali
09-17-2011, 05:06 PM
1975 FJ-40


Hey Matt, thanks for this great thread!! I am trying to learn the STOCK carb setup as well and this got me to go out and check my setup. I verified all the linkages and vacuum lines, put the paper clip on the front diaphragm linkage and took it for a drive, not only did it NOT move but the motor seems to decelerate when I floor it. So, I pulled the vacuum assembly and verified that it does work, blew into the port feeding the vacuum module and could hear it blowing into the carb body which I can only assume, this is where the vacuum is being drawn from (funny, my emission control repair manual does not even mention this module nor the secondary acceleration). I am at a loss as to why the secondary is not opening, everything seems to be correct. I had Kim push the throttle to the floor while I verified that the linkage IS free to move and open the secondary venturi, could it be that I am not drawing enough vacuum to open it? if so, why? it seems to drive just fine as long as I am not asking for full throttle..

That seems weird Brian. In fact, I was crossing my fingers that my only problem would be the bracket on the firewall. I wasn't sure what to do if I fixed that and it still didn't work. The operation of the secondary isn't really covered in your Emissions manual, but the Engine FSM shows a cutaway schematic and shows how to disassemble the secondary diaphragm housing. The Haynes manual shows the cutaway schematic as well. The source of vacuum is just downstream of the venturis, and there appears to be an orifice in that location, so theoretically if the throttle plates are open, drawing air through the venturis and you are giving yourself enough duration to overcome the effect of the orifice, it should operate. The fact that you are experiencing a stumble or hesitation at WOT could be the culprit though. Have you done all of your basic checks? Vacuum leaks (vacuum readings), timing, valve adjustment, accelerator pump functioning properly? 1975 Cruisers will also have the auxiliary accelerator pump (AAP), so you will need to verify that that is working properly as well.

One other thing, while checking the vacuum lines I pulled the throttle positioner diaphragm line and pulled vacuum on it, it does move but it does not hold vacuum at all with the linkages returning to their normal position almost immediately after drawing vacuum, again, my manual does not go into the operation of this unit only the complete circuit, is this supposed to hold vacuum and keep the linkage in position as long as vacuum is being applied?

as always, thanks for the help!!! :thumb:

Brian

Looking at the Emissions FSM to verify, I believe the TP diaphragm should hold its position while vacuum is being applied, because at idle it is the vacuum that keeps the TP diaphragm pulled away from the throttles, allowing them to close fully and allowing your idle circuit to function properly and for you to make adjustments to your carb properly. Sounds like you might need to find another TP diaphragm (I don't think they are rebuildable), or test your vacuum-producing equipment to make sure it's not leaking, giving you false results. Actually, the best check would be to let the engine idle and see if the TP diaphragm remains retracted.

Rezarf
09-17-2011, 07:00 PM
Wow Matt, thanks for the pics bro, that really helps. I am going to see what I see later tonight if I can get my :Princess: to stomp the pedal a few times.

subzali
09-17-2011, 09:36 PM
Turns out my TP diaphragm doesn't work either. I think. EDIT: It's not my TP diaphragm, but maybe the VSV. I need to look into it more.

PhatFJ
09-18-2011, 08:21 AM
Thanks for the reply Matt!! I have done a complete tune on the 2F and like I say it does run really well as long as I am not asking it to produce power at full throttle, even the idle control seems to work well, when I come to a stop the idle is noticeably higher and I can hear it step down, so I am not convinced that the Throttle Positioner is not working properly. The PO had the carb rebuilt and I am not sure it was done properly and I think it was done with a low end rebuild kit as he did give me the box. This being said, I think I am going to remove the carb and totally go through it by the book. Any advise on rebuild kits? I did look at the kit that SOR sells, I do not know if there is the same kit available locally or not.. One other thing on the Throttle Positioner, the 2F manual does say to "connect hose to choke breaker diaphragm (throttle positioner) and suck the hose with mouth. The diaphragm should move. If not, replace it". Well if yours is like mine, it does move but it just does not stay in the position.. Don't know, my choke works well and idle seems to work well :confused:

Thanks again bro!!
By the way GREAT PICS!!! I don't know how you get some of those shots, I could not get a camera in some of those positions..

Brian

subzali
09-18-2011, 08:59 PM
Keyster kits are pretty popular for carb rebuilds, but supposedly the Hygrade kit is better. You can buy either of them on ebay.

I have a pretty small camera I guess :)

kurtnkegger
09-18-2011, 09:03 PM
Matt, my carb secondary is activated by a switch on the throttle when floored, and goes through the emissions computer that releases the vacuum. If you have yours freed of the computer, perhaps you aren't getting the vacuum you need when you need it...

subzali
09-18-2011, 09:13 PM
Interesting Kurt. Mine is definitely not controlled by the computer in any way, and wasn't designed to from the factory. Maybe it's a California emissions thing? I'll have to check yours out sometime.

subzali
09-19-2011, 08:13 AM
...Well if yours is like mine, it does move but it just does not stay in the position.. Don't know, my choke works well and idle seems to work well :confused:

Brian,

I just did the mouth-vacuum test on my TP diaphragm this morning. It pulls back and stays back as long as I keep the vacuum applied. But at idle it's not engaged like I think it should be. Maybe my VSV is not working. Hm.

PhatFJ
09-19-2011, 09:50 AM
Matt, my carb secondary is activated by a switch on the throttle when floored, and goes through the emissions computer that releases the vacuum. If you have yours freed of the computer, perhaps you aren't getting the vacuum you need when you need it...

Hey Kurt, looking at my emission control for 1975. The throttle position switch (at full throttle) activates the "power valve control system (2f engine only)", this does have the computer, vsv, red thermo s/w and vacuum surge tank as part of the same system.. I went through this system as well using a vac gauge and dmm, pulled the red thermo s/w and tested it with hot water on the stove.

PhatFJ
09-19-2011, 10:03 AM
Keyster kits are pretty popular for carb rebuilds, but supposedly the Hygrade kit is better. You can buy either of them on ebay.

I have a pretty small camera I guess :)

Thanks Matt, I pulled the carb yesterday to look it over. I noticed that the spring at the end of the secondary shaft was not fully wrapped to the stop, thus not applying enough tension to the secondary TV shaft. I fixed this, took it for a drive and it seems to be better but still not the power I think it should have. I will do another paper clip test today. Hey, looking at the 2f manual this morning I noticed that there are 2 springs in the picture of the secondary diaphragm, I am curious if the one in mine is to heavy, not allowing the diaphragm to retract :confused: I did look for the Hygrade 791b kit and could only fine it at Woody's $40.00 + $11.00 shipping :eek: Oh, I also pulled one of the carb mounting studs out of the manifold so I got to do a helicoil repair yesterday as well.. :( Are we having fun yet???

SteveH
09-19-2011, 11:20 AM
CarQuest had a kit for my '78 in stock last year - $50ish. It did contain the secondary diaphragm. Not sure whose kit it was, but it was repackaged in a CarQuest box.

subzali
09-19-2011, 07:09 PM
I checked the operation of the TP diaphragm tonight (among other things). I hooked it to manifold vacuum and it retracted, as I suspected. It remained in the retracted position as long as I held vacuum on it, but returned to its rest position when vacuum was removed.

Rezarf
09-22-2011, 10:57 PM
So are you popping wheelies yet or what? :D

subzali
09-23-2011, 08:03 AM
I'll find out Sunday morning how it really does. Turns out CJ7 Matt is going to come on the Argentine Run, so we'll be able to "race" up I-70 :rolleyes: :snail:. I'm hoping to at least keep up with him, if not outrun him due to my gearing advantage. I hope to also have a speedometer cable installed by Sunday, so I'll be able to get some speed readings in addition to rpm readings.

Uncle Ben
09-23-2011, 11:11 AM
I'll find out Sunday morning how it really does. Turns out CJ7 Matt is going to come on the Argentine Run, so we'll be able to "race" up I-70 :rolleyes: :snail:. I'm hoping to at least keep up with him, if not outrun him due to my gearing advantage. I hope to also have a speedometer cable installed by Sunday, so I'll be able to get some speed readings in addition to rpm readings.

I can see it now.....

http://forum.ih8mud.com/attachment.php?attachmentid=543118&d=1312041302

Uncle Ben
09-23-2011, 11:13 AM
I'll find out Sunday morning how it really does. Turns out CJ7 Matt is going to come on the Argentine Run, so we'll be able to "race" up I-70 :rolleyes: :snail:. I'm hoping to at least keep up with him, if not outrun him due to my gearing advantage. I hope to also have a speedometer cable installed by Sunday, so I'll be able to get some speed readings in addition to rpm readings.

I can see it now.....

http://image.off-roadweb.com/f/features/9710784+pinline_medium/0803or_09_z+tlc_fj40_land_cruiser_score_baja_1000+flying.jpg
http://forum.ih8mud.com/attachment.php?attachmentid=543118&d=1312041302

subzali
09-23-2011, 01:21 PM
Maybe more along the lines of this bad boy...
http://www.sor.com/shared/SlideShows/SOR_73FJ40-Baja1K/001.jpg

:D

subzali
10-03-2011, 09:14 AM
Okay, after a couple runs up I-70 to Georgetown, I'm very happy with the results...:D

Going up to Beaver Brook/Mount Vernon Canyon, the lowest rpm I got to was about 2600 rpm (58 mph). For most of the climb, my tach sat at about 2750 rpm (62 mph). On the first flat, my tach climbed up to about 3250 rpm (73 mph). On the way back on Floyd Hill, I got caught behind someone going a little slow and my tach dropped to about 2400 rpm (54 mph). I dropped the tranny into 3rd, ran it up to 3700 rpm, then upshifted to 4th again and was able to hold 2700-2750 (61-62 mph) the rest of the way up the hill.

From memory, I used to only be able to do about 48-50 mph, with spurts up to maybe 55 mph on the first flat spot going up Mt. Vernon Canyon. I'll have to double check my notes though. In any case, big difference. I can definitely feel it in my butt meter as well.

kurtnkegger
10-03-2011, 03:49 PM
Matt, I'm going to have to talk to you this coming meeting so you can school me on what/how to check for more power. I am currently running like you describe your conditions from past.

I'm just enough of an idjit, that I'm getting lost in the thread...

Uncle Ben
10-03-2011, 04:25 PM
Matt, I'm going to have to talk to you this coming meeting so you can school me on what/how to check for more power. I am currently running like you describe your conditions from past.


:D:thumb::thumb:http://www.hallbrosracing.com/photos/bry_56_test2_sm.jpg

Rezarf
10-03-2011, 06:24 PM
Add a dash a purple and you're close Matt ;)

http://graphics8.nytimes.com/images/2006/11/10/automobiles/12sema_slidesix.jpg

kurtnkegger
10-04-2011, 09:22 PM
Alright Matt, Tore in to my linkage, and set up...My bracket at the carb was openned up, and getting the linkage to not operate quite right. Going to hit the bracket, and the linkage with the welder, and get things tightenned up. Doing the paperclip thing, I only get about 1/4 inch of travel. How do I manually create vacuum to it?

Every hose I've sucked on gets me nowhere...I feel like Linda Lovelace....

subzali
10-04-2011, 10:28 PM
The vacuum comes from inside the secondary diaphragm housing. If you take the housing off the carb you'll see the hole. It leads to the area right at the venturi, so there is no vacuum unless there is air running past the carb venturi. If the paperclip is traveling at all then you're in good shape, as far as I can tell. Will you have your 40 tomorrow night?

kurtnkegger
10-05-2011, 11:32 AM
Planning on bringing it. Since my bracket was openned up from wear, I rounded the hole, and put a brass bushing in there for the pivot point. I filled the worn away groove in the shaft with a little weld...smoothed, and made a couple of aluminum washers for spacers to keep everything in place.

It should only take a few minutes to install...and then I'll have to readjust the throttle linkage...only after lengthening it for enough travel to move the gate did I discover the worn out carb bracket.

subzali
10-05-2011, 11:39 AM
Looks like you have it pretty well in hand Kurt! Yours was definitely not as worn as mine though!

Rzeppa
10-06-2011, 04:29 PM
What is this throttle positioner diaphragm business? I know FI needs to know the TP, but this sounds like something else. Does it have any function at idle, or is it only for throttle positions above idle? I need to look this up when I get home and see if it might have something to do with my 60 stall at idle problem...

corsair23
10-06-2011, 04:48 PM
Every hose I've sucked on gets me nowhere...I feel like Linda Lovelace....

:lmao: - I'm not sure Radar is old enough to get the reference :hill:

subzali
10-06-2011, 04:51 PM
What is this throttle positioner diaphragm business? I know FI needs to know the TP, but this sounds like something else. Does it have any function at idle, or is it only for throttle positions above idle? I need to look this up when I get home and see if it might have something to do with my 60 stall at idle problem...

The TP diaphragm holds the throttle plate slightly open when decelerating at high speeds, to prevent an overly rich mixture. I think it also has a function as a choke breaker on some models.

:lmao: - I'm not sure Radar is old enough to get the reference :hill:

Totally over my head, but I have a feeling it's something I shouldn't look up on my work computer :hill:

Rzeppa
10-07-2011, 11:33 AM
I checked my manual and there is no reference to a throttle positioner diaphragm. On my 60 I have 3 vacuum diaphragm actuators on my carb: secondary, AC idle kick up, and choke breaker. The choke breaker just opens the choke a little bit when it is fully closed; once there is vacuum from the engine running it allows a little bit of air to get past the choke butterfly. I don't think it does anything to the throttle, when the choke is closed, the throttle is already partially open from the fast idle.

subzali
10-07-2011, 11:55 AM
Jeff, it looks like your 60 carb is a little different than my '77 FJ40 carb:
FJ60 carb:
http://www.sor.com/shared2010/image/042/042-01M-1.jpg

'77 FJ40 carb:
http://www.sor.com/shared2010/image/042/042-01J-1.jpg

On my carb, the choke breaker diaphragm also controls the fast idle screw, or throttle positioner. This doesn't seem to be the case with yours.

By the way, this is different than a throttle positioning sensor. It's not detecting throttle position in any way, but it's rather holding the throttle plates open at certain times.

Rzeppa
10-07-2011, 12:15 PM
Jeff, it looks like your 60 carb is a little different than my '77 FJ40 carb:

On my carb, the choke breaker diaphragm also controls the fast idle screw, or throttle positioner. This doesn't seem to be the case with yours.

By the way, this is different than a throttle positioning sensor. It's not detecting throttle position in any way, but it's rather holding the throttle plates open at certain times.

I don't think the choke breaker "controls" the fast idle screw. The fast idle screw controls the throttle position when the choke is pulled out manually by the vehicle operator. The choke breaker just opens the butterfly a little so the engine can get enough air to run.

And of course I know what a TP sensor does on a FI system LOL! I spent plenty of time with that on my daughter's 1985 4runner! ;)

I had just thought maybe I was overlooking some subsystem or other as I tried to determine why my 60 sometimes stalls when you disengage the clutch. The conditions that my issue occurs is with the engine at normal operating temperature and the choke fully open, thus the choke breaker has no effect.

subzali
10-07-2011, 01:42 PM
My system doesn't work properly because my VSV is toast for some reason, but it looks to me like my CB/TP diaphragm operates like this:
-at idle there is vacuum acting on the diaphragm, so it pulls the lever for the CB, as you say keeping just a little bit of air running through the carb as soon as the engine starts pulling vacuum. It also pulls the fast idle screw up and away from the throttle linkage so the fast idle is not in effect unless the choke is pulled.

-at high speed (activated by the VSV), there is no vacuum pulling on the diaphragm, allowing the fast idle screw to contact the throttle linkage when the throttle is at rest. During deceleration, the throttle plate would normally be closed. According to my Emissions FSM, this causes an overly rich mixture. But because the fast idle screw is allowed to rest on the throttle linkage at high speeds (because no vacuum is acting on the diaphragm), it keeps the throttle plates open just a tad to even out the A/F ratio.

Again, I have not been able to verify these results yet because my VSV is toast, but it's what the FSM says, and when I manually apply vacuum to the diaphragm I can recreate the action.

I figured you knew what a TP sensor did, but your earlier post made it sound like you were chasing after something that wasn't there, and I wanted to clarify my meaning.

subzali
10-07-2011, 04:24 PM
Wow, lots of questions Brian! First let me catch up with some more photos and then I'll try to address your questions as best as I have been able to find out.

First, these pictures show my old bracket, as removed, and Dean's new bracket installed. My old bracket has a clip that holds the speedo cable, Dean's doesn't, so I might still repair my old bracket and re-install it. I think this is because in some years (like '76) the speedo cable doesn't go straight to the t-case; it first goes to a secondary speedo that controls things like the EGR maintenance warning light.

Wow, so this thread has taken a huge tangent since page 3. Getting back to the matter at hand, AHorseThief helped me :weld: the hole back up in my bracket (that's why I was in my grunge clothes at the meeting Wed. night). Now I just have to figure out how the big the hole is supposed to be and where exactly it's supposed to be located, and drill a new one. I already have new grommets to put on, then I can hook it back up and have the little hook for my speedo cable back again as well! One little step at a time!

wesintl
10-07-2011, 04:29 PM
I just have to figure out how the big the hole is supposed to be and where exactly it's supposed to be located,

:eek: :rolleyes:

kurtnkegger
10-09-2011, 09:09 PM
Matt, if you would like to reference my bracket for drilling your new hole, I would be glad to let you measure mine...If you aren't in a hurry, I could do a pencil rub on the bracket, and you could get the right orientation from that...

subzali
10-09-2011, 09:38 PM
Thanks Kurt, but I have the one from Dean that I have installed and am using at the moment that I can measure :thumb:

subzali
10-30-2011, 10:49 AM
An interesting update from driving around this morning:
-I drove over to RMC, going up Quebec, across on Belleview, then up Federal, and back. I was testing to see if the secondary would open, so when I was accelerating I was taking the engine up to 3500 rpm or so on each shift, and flooring it the whole time during accelerations. A few times I stopped and checked the paper clip I had on the actuating rod, and it wasn't moving :confused: :banghead:

So I had an idea: On the way home I got on I-25 at Belleview and took it down to Arapahoe, flooring it and revving the engine to about 3500 rpm, even taking it up to that rpm in 4th gear (about 80 mph) :eek:

When I got home (a few turns off of I-25 off Arapahoe), I checked the paperclip again. It had moved!

So, moral of the story is that I guess the secondary doesn't kick in (on a vacuum-actuated version), until you have a sustained load at high rpm. There must be a time-delay factor there, like an orifice or something built into the system.

Anyway, when the paperclip did move, it moved about 1/2 inch down the shaft: see the before and after pictures:
Before:
http://www.risingsun4x4club.org/forum2/attachment.php?attachmentid=25123&stc=1&d=1316296272

After:

L43dean
10-30-2011, 10:45 PM
Is it possible that the clip is on snug enough to act like a restricter?

subzali
10-30-2011, 10:48 PM
No, I checked my theory about the orifices just now, and sure enough according to the diagram in the FSM they are there. So the carb has to see sustained high velocity airflow through the venturis before it will open the secondary up. It won't just open because you mashed the pedal to the floor.

subzali
04-08-2012, 06:13 PM
Any thoughts? :confused:

DanS
04-08-2012, 06:15 PM
Any thoughts? :confused:

WHAT??!?!?! I can't hear you right now, I'm going real fast!

:thumb:

subzali
04-08-2012, 06:33 PM
That's part of it ;)

I guess my question is this:
According to my calculator and others such as this one: http://www.grimmjeeper.com/gears.html

A stock FJ40 (29" tires) should be turning 4000 rpm at 85 mph. But according to my tach/speedo combination 4000 rpm is only 75 mph. My actual road speed with 31" tires at 4000 rpm should be 90 mph, but if my tach and speedo are reading accurately my actual road speed is probably closer to 80 mph. What gives?

I guess I need to get a GPS...:o

kurtnkegger
04-08-2012, 08:46 PM
I guess I need to get a GPS...:o

There's the answer Matt!! Stop all the math madness!! :beer:

rover67
04-08-2012, 11:08 PM
That's part of it ;)

I guess my question is this:
According to my calculator and others such as this one: http://www.grimmjeeper.com/gears.html

A stock FJ40 (29" tires) should be turning 4000 rpm at 85 mph. But according to my tach/speedo combination 4000 rpm is only 75 mph. My actual road speed with 31" tires at 4000 rpm should be 90 mph, but if my tach and speedo are reading accurately my actual road speed is probably closer to 80 mph. What gives?

I guess I need to get a GPS...:o

4k sounds like a lot for the 2F. :wrench:

Hulk
04-09-2012, 12:31 AM
4k sounds like a lot for the 2F. :wrench:
90 mph sounds like a lot for an FJ40.

subzali
04-09-2012, 08:05 AM
FJ60 redline is at 4k right? And Wes did 80 in his '64. And Toyota advertised the FJ40 to be able to cruise at 85 mph all day with 7 grown men inside :hill:

Not saying I make a regular occurrence of this kind of driving, but just want to be sure that it's possible.

60wag
04-09-2012, 08:30 AM
Any thoughts? :confused:

That dash rug has to go.



My '82 2F sounded like it was going to come apart at 3200 rpm.
My rebuilt '84 2F was relatively quiet and quite smooth up to 4200 rpm.

I think your speedometer is misreading at that speed.

DaveInDenver
04-09-2012, 08:39 AM
I guess I need to get a GPS...:o
Come now soon-to-be PE, 60MPH is how many miles per minute? Bueller, Bueller?

Mile markers, a flat section of highway, a steady foot and the second hand on your watch. Assuming you wind your watch (and let's be honest, who doesn't, right?), you don't even need power or satellites. That is the true Cruiser speedo checking method.

farnhamstj
04-09-2012, 08:44 AM
:)

subzali
04-09-2012, 08:47 AM
That dash rug has to go.

Yes. I inherited that from the PO and haven't been able to justify replacing it considering everything else the 40 really needs...

rover67
04-09-2012, 09:53 AM
Come now soon-to-be PE, 60MPH is how many miles per minute? Bueller, Bueller?

Mile markers, a flat section of highway, a steady foot and the second hand on your watch. Assuming you wind your watch (and let's be honest, who doesn't, right?), you don't even need power or satellites. That is the true Cruiser speedo checking method.

before I had a GPS I'd spend my time on the hwy doing this. kinda fun.

bomber22
04-09-2012, 11:49 AM
And Toyota advertised the FJ40 to be able to cruiser at 85 mph all day with 7 grown men inside

somehow i just can't see that happening in a 40ty.

AHorseThief
04-15-2012, 11:02 AM
Yes. I inherited that from the PO and haven't been able to justify replacing it considering everything else the 40 really needs...

Get a new dash from this guy http://fj40dash.com, then you can hit it with a hammer, miss and get a new windshield too!

subzali
04-15-2012, 05:56 PM
Get a new dash from this guy http://fj40dash.com, then you can hit it with a hammer, miss and get a new windshield too!

yawn. Needs storage.

subzali
06-24-2012, 01:09 PM
Finally got some video from the drive up I-70 to Georgetown a couple weeks ago. I didn't get a video of Mt. Vernon Canyon (drat):

Genesee:
Genesee WB (http://www.risingsun4x4club.org/uploads/subzali/MVI_7137_small.wmv)

Floyd Hill WB:
Floyd Hill WB (http://www.risingsun4x4club.org/uploads/subzali/MVI_7138_small.wmv)

Floy Hill EB:
Floyd Hill EB (http://www.risingsun4x4club.org/uploads/subzali/MVI_7183_small.wmv)

Registered 55-60 mph (actual 60-65 mph I'm pretty sure with 31" tires) on a 6% grade, going up from 6000 feet.

Let the snail races begin! :D :snail:

nattybumppo
06-24-2012, 02:18 PM
That sounds great Matt. I wish my 40 would do that! My list of 40 projects grows faster than my son. With 31s on, my 40's speedo is very close to right on when I pass through the radar speed trailers.

kurtnkegger
06-24-2012, 03:10 PM
Matt, with your speedo broken, your gauge looks EXACTLY like mine...I need to get together with you and do a little brain storming...I'm jealous of the power you have up those hills...

akingf5371
08-22-2012, 04:09 PM
Matt, I just noticed I lost my rubber grommet like you did in the first picture! Mine wasn't as washed out as yours though. I had read this thread a few months ago and was bummed because you mentioned that SOR didn't have the part. I looked on MUD after this and found a post you made that mentioned you think part number 61 is the actual grommet that the torque rod goes through! So, ordered and thanks for your due diligence!

AKcruiser
08-23-2012, 05:31 PM
I would be scared to death to drive my 40 at anywhere near the speeds you guys drive at. Slow and steady. 55-60 is my tops.

Im running a Troll Hole carb, and it really helped with power especially on the low end.

Im pretty sure my secondary is working, I know how it drove when it wasn't working, but Im still going to try the paper clip trick. Good hint.

Jenny Cruiser
08-23-2012, 10:40 PM
Nice. I like my light switch where it is, but I will have a tach one day! Your 77 is a lot quieter than mine rolling on 33x12.5 MTs is at those speeds. When my speedo reads ~63-64ish Mr. Sat Nav says I'm doing 70 and that I pulled from 70 to 80 up a 4% grade tonight in 5th gear on the way back from Nashville. Very pleased to see that. :) I have no idea what the compression is on my motor, but it was blue printed and balanced 18K ago and people have told me it's peppier than their 2fs. What is considered good compression numbers on a 2f?

Rzeppa
08-23-2012, 11:39 PM
What is considered good compression numbers on a 2f?

150 PSI at sea level is what the factory says. 130 or so down in Denver is pretty good.