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cbmontgo
04-20-2010, 09:34 AM
Where do you guys source smaller orifice sizes for stock Aisin carb jets? I've got a '76 FJ40 that needs to be jetted for this elevation. Unfortunately, the spare high altitude jets seem to have gone away in '74.

Do I just need to replace the primary jets or the others as well? Any orifice size recommendations for our elevation in the Denver area?

Just got this rig up here and it runs REALLY rich. I'm going to rebuild the carb while I'm in there.

RicardoJM
04-20-2010, 11:32 AM
I tried Import Carb Warehouse and they did not stock them. Toyota no longer has them. I pulled a couple from a Corolla, but they were not even close to the size I was needing. I was fortunate enough to get some jet advice from JimC on MUD (http://forum.ih8mud.com/40-55-series-tech/332115-carb-jets-5280-feet.html) - but could not find a 60 for one of slow jets. I went with a 50 in both.

My rebuild (http://risingsun4x4club.org/forum2/showthread.php?t=11570&highlight=Aisan+rebuild) has been running in my 40 for over 4 months and is doing just fine. Take your time, plenty of pictures and notes and enjoy the experience. If you have any questions, I'm happy to share what I can.

cbmontgo
04-20-2010, 01:13 PM
I tried Import Carb Warehouse and they did not stock them. Toyota no longer has them. I pulled a couple from a Corolla, but they were not even close to the size I was needing. I was fortunate enough to get some jet advice from JimC on MUD (http://forum.ih8mud.com/40-55-series-tech/332115-carb-jets-5280-feet.html) - but could not find a 60 for one of slow jets. I went with a 50 in both.

My rebuild (http://risingsun4x4club.org/forum2/showthread.php?t=11570&highlight=Aisan+rebuild) has been running in my 40 for over 4 months and is doing just fine. Take your time, plenty of pictures and notes and enjoy the experience. If you have any questions, I'm happy to share what I can.

Thanks, Ricardo. What a cool writeup! I am about to take some time and read through it prior to my upcoming carb rebuild.

I rebuilt my FJ60 Aisin carb in 2007, but I don't know why I am nervous about this FJ40 carb. I guess the jetting thing has me concerned, especially since Toyota no longer has them and I am having a hard time running these parts down.

MDH33
04-20-2010, 01:15 PM
I have some spare jets. Let me know what sizes you decide to run and I'll see what I have.

cbmontgo
04-20-2010, 01:21 PM
I have some spare jets. Let me know what sizes you decide to run and I'll see what I have.

Thanks Martin! Let me get this thing torn down and I'll PM you.

I've read that some people up here use 1.08 mm primary jets (maybe see if you have a size close to that?), but do I also need to change out the power valve and the slow valve?

MDH33
04-20-2010, 01:35 PM
Thanks Martin! Let me get this thing torn down and I'll PM you.

I've read that some people up here use 1.08 mm primary jets (maybe see if you have a size close to that?), but do I also need to change out the power valve and the slow valve?


What jets do you currently have?

The recommended starting place for jets at higher elevation (according to Jim C and tested by myself and Ricardo) are:

112 or 114 Primary
180 Secondary
50/60 or 50/50 slow
and 60 Power Valve

RicardoJM
04-20-2010, 01:54 PM
I have some spare jets. Let me know what sizes you decide to run and I'll see what I have.


I've read that some people up here use 1.08 mm primary jets (maybe see if you have a size close to that?), but do I also need to change out the power valve and the slow valve?

Once you decide what you want to run, I'll check what I have that you need. It all begins with first learning what you have in there.

I am assuming this is your new FJ40 from AZ. Before diving into the carb rebuild have you gone through some tune up basics and checked for vacuum leaks? New plugs, dizzy cap, rotor, points (if you don't have electronic ignition), valve adjustment and timing check will give you a good baseline. Fresh 15w40 and filter don't hurt. If there are any vacuum leaks, you will not ever get the carb working well until they are gone. :thumb:

cbmontgo
04-20-2010, 01:55 PM
What jets do you currently have?

The recommended starting place for jets at higher elevation (according to Jim C and tested by myself and Ricardo) are:

112 or 114 Primary
180 Secondary
50/60 or 50/50 slow
and 60 Power Valve

I need to take it apart and see which ones I have. It ran perfectly in Arizona when I dropped it off to be shipped here, but then had some starting issues in Phoenix and runs like hell here. I'm not sure what the issue is, but I am guessing that leaning it correctly is a start.

It only drives/idles if you throttle it up at the carb. If you give it gas, it bogs down and dies. Spits nasty black smoke and smells strongly like gas.

cbmontgo
04-20-2010, 02:00 PM
Once you decide what you want to run, I'll check what I have that you need. It all begins with first learning what you have in there.

I am assuming this is your new FJ40 from AZ. Before diving into the carb rebuild have you gone through some tune up basics and checked for vacuum leaks? New plugs, dizzy cap, rotor, points (if you don't have electronic ignition), valve adjustment and timing check will give you a good baseline. Fresh 15w40 and filter don't hurt. If there are any vacuum leaks, you will not ever get the carb working well until they are gone. :thumb:

I am trying to order the cap, rotor, wires, etc. from Go Toyota on Arapahoe, but they are taking forever and don't seem to be very interested in my business. I really don't want to buy aftermarket if I can avoid it. I did change the oil and filter yesterday. Have not checked timing or adjusted valves yet.

I have visually inspected for vacuum leaks, but it's really strange that it had a hard time starting in Phoenix to be loaded onto the truck after it ran perfectly for 100 miles when I picked it up in Congress, AZ. Could this be an intake manifold crack causing the vaccum leak? I figure that it needed a carb rebuild anyway and I can at least isolate that as an issue. My FJ60 acted similarly when it needed a rebuild.

SteveH
04-20-2010, 02:39 PM
Given how all my federal-spec (low elevation) trucks have run at 7000' (my house), I don't think jetting is the first place I'd look. Do a 100% by the book tuneup (timing, idle mix, etc.) and check vacuum advance function, and look for vacuum leaks, etc. and see if that doesn't help greatly. My truck does run rich at very high elevations -12K, but that would be normal for any carburetted vehicle. Rejetting is a pain, IMO...start with easier stuff first.

sno bored
04-20-2010, 03:46 PM
I need to figure out what jets I am going to need for "extra high altitude". I'm sure the pig was set up for Denver, but I live at 10,000 feet and I am planning on driving my pig to my office in a few days 11,000+ feet. I will see how it goes.

corsair23
04-20-2010, 03:56 PM
I am trying to order the cap, rotor, wires, etc. from Go Toyota on Arapahoe, but they are taking forever and don't seem to be very interested in my business.


Call Joe Borger over at Groove Toyota on Broadway and tell him the RS guys sent you...Jerry is a good contact there as well. Great guys, and I'm sure they'll treat you right and try to get you whatever parts you need that they can get :thumb: - Come up the back way from the Pines and it might even be a shorter (distance) drive for you.

MDH33
04-20-2010, 04:38 PM
I need to figure out what jets I am going to need for "extra high altitude". I'm sure the pig was set up for Denver, but I live at 10,000 feet and I am planning on driving my pig to my office in a few days 11,000+ feet. I will see how it goes.

It's tough because if you get it to run well at that elevation, you'll have to change it to drive normally down in the lowlands. I would opt to go for the jet sizes we listed. It won't be optimal for 10000 feet, but at least it will run reasonably everywhere from Denver on up to the highest passes.

ttubb
04-20-2010, 08:26 PM
For what it is worth, my carb was rebuilt and used the stock jets when the engine was rebuilt last year. Bill Lee of Bill's Toy Shop in Siver City NM did the work

I am at 10,000 in Crested Butte and wheel up over 12,000 and have had no issues with the carb, either starting or running at altitude. I do have the timing set at 12 degrees BTDC. Hope this helps. Terry

cbmontgo
04-20-2010, 09:32 PM
Thanks guys, and thank you Jeff for the Groove Toyota recommendation. I am trying to avoid mudslinging here, but Go Toyota has given me crap service so far. They don't seem to understand that a load of FJ40 parts may bring in more revenue that an engine overhaul on a Scion, but I see where we "old schoolers" stand now.

On another note, I got my 40 running great today. Turns out the choke had been tampered with by the shipper and the linkage had been manually pulled into place in full choke "mode". This gave me a very rich mixture and a very high idle. Funny that the philips choke cable screw was stripped recently as well. Someone knew that they screwed it up.

I am still going to rebuild the carb, but I may try the emissions test before I rejet and see if I pass or fail. This should be a good indicator of a rich mixture I assume? It may help me get it dialed in just right.

corsair23
04-20-2010, 10:43 PM
I am still going to rebuild the carb, but I may try the emissions test before I rejet and see if I pass or fail. This should be a good indicator of a rich mixture I assume? It may help me get it dialed in just right.

FWIW, my '74 that came from California passed emissions testing with no changes when it got here...That was almost 5 years ago now so things may have changed...Oh, and my '74 runs like crap at higher elevations...Still need to fix that issue.

RicardoJM
04-21-2010, 06:47 AM
Thanks guys, and thank you Jeff for the Groove Toyota recommendation.

On another note, I got my 40 running great today. Turns out the choke had been tampered with by the shipper and the linkage had been manually pulled into place in full choke "mode".
I may try the emissions test before I rejet and see if I pass or fail.

I've always received great service from Jerry at Groove and he's been a great supporter of the club.

Great news on getting it running:thumb:. If I understand the issue correctly, the choke cable has been set so that the butterfly valve would not open fully?

I understand the law has changed a bit (so it may be different now), if you don't pass, you get a free retest within 10 days. There is a shop on Broadway (just across the street from Groove) that has the equipment to check emissions. I had them tune my carb (after a rebuild) to dial the truck in so that it passed.

cbmontgo
04-21-2010, 09:07 AM
I've always received great service from Jerry at Groove and he's been a great supporter of the club.

Great news on getting it running:thumb:. If I understand the issue correctly, the choke cable has been set so that the butterfly valve would not open fully?

I understand the law has changed a bit (so it may be different now), if you don't pass, you get a free retest within 10 days. There is a shop on Broadway (just across the street from Groove) that has the equipment to check emissions. I had them tune my carb (after a rebuild) to dial the truck in so that it passed.

Thanks, Ricardo.

That is correct about the choke. The butterfly valve was sprung shut because the choke was basically fully engaged all the time. This caused it to run super rich and fouled my plugs.

I'll look into that shop on Broadway if I don't pass. I am also planning on going down a jet size or two, depending on the one that I have. I hope to start tearing the carb down this weekend.

cbmontgo
04-21-2010, 09:10 AM
Just left a message for Joe over at Groove Toyota.

Rezarf
04-21-2010, 09:25 AM
Glad to hear you got it going.

Drew

cbmontgo
04-21-2010, 09:26 AM
Joe is a super cool guy...he is all over it! Thanks Jeff...

Blackdiamond72
04-21-2010, 09:30 AM
Move to the mountains, no emissions!

Glad to see you found the pressing issue.

cbmontgo
04-21-2010, 10:22 AM
Move to the mountains, no emissions!

Glad to see you found the pressing issue.

I almost did and regret it sometimes! I'd love not to mess with this stuff...

corsair23
04-21-2010, 12:38 PM
Joe is a super cool guy...he is all over it! Thanks Jeff...

Glad it worked out :thumb: - Both Joe and Jerry are great guys and very helpful :)

cbmontgo
04-21-2010, 03:15 PM
Glad it worked out :thumb: - Both Joe and Jerry are great guys and very helpful :)

Parts are ordered and we are good to go. Still haven't heard back from Go Toyota after a week. I know who I am doing business with from here on out...thanks Jeff!

corsair23
04-21-2010, 04:47 PM
Parts are ordered and we are good to go. Still haven't heard back from Go Toyota after a week. I know who I am doing business with from here on out...thanks Jeff!

:thumb: - We like to help support the dealerships that support the club...I know they all appreciate the business we give them, especially in these tough times. Say hi to the boys down there when you pick up the parts.

subzali
10-19-2010, 01:57 PM
Does the carb have to be dismantled pretty far to determine what jets it has?

cbmontgo
10-19-2010, 02:06 PM
Does the carb have to be dismantled pretty far to determine what jets it has?

Hey Matt,

No, you can actually remove the jets with the carb on the vehicle. Just remove the two front bolts by the sight glass and get a long screwdriver to reach the jets way inside...

subzali
10-19-2010, 02:43 PM
Okay, I guess I knew that...

What about the power valve and the slow jets?

MDH33
10-19-2010, 02:48 PM
Okay, I guess I knew that...

What about the power valve and the slow jets?

you can remove the air horn and access them, but at that point, you might as well just pull the carb and disassemble on the bench. :thumb:

subzali
11-07-2010, 07:56 AM
Hey Matt,

No, you can actually remove the jets with the carb on the vehicle. Just remove the two front bolts by the sight glass and get a long screwdriver to reach the jets way inside...

How do you get the jets to come out of the fuel bowl when the carburetor is installed on the engine? It's kinda hard to reach in that M10 hole with your fingers ;)

And how do you get the jets back in and get them threaded properly? Is it something that a person just has to try and it'll work? Or is there a technique?

cbmontgo
11-24-2010, 01:07 PM
How do you get the jets to come out of the fuel bowl when the carburetor is installed on the engine? It's kinda hard to reach in that M10 hole with your fingers ;)

And how do you get the jets back in and get them threaded properly? Is it something that a person just has to try and it'll work? Or is there a technique?

Matt,

It is actually pretty easy once you find where the jets are after removing the two front bolts at the fuel bowl. If you unscrew the jet(s) and lose them in the fuel bowl, you can easily remove the air horn and get to them that way. You'll just need a narrow flathead screwdriver and make sure you don't strip the notch in the jet. No need to remove the carb from the truck at all.

By the way, I came across two new OEM high altitude jets through Toyota in Albuquerque and couldn't pass up the super rare find. The 40 runs great (although probably a little rich), so I am going to see how she does at elevation with the 1.14mm primary and 1.80mm secondary jets. If it's too lean, I'll just put the stock 1.44mm and 2.30mm back in.

PabloCruise
12-24-2012, 09:08 AM
Looking forward to reading this thread - getting geaked on all the good carb talk these days!

PabloCruise
12-27-2012, 12:55 PM
What jets do you currently have?

The recommended starting place for jets at higher elevation (according to Jim C and tested by myself and Ricardo) are:

112 or 114 Primary
180 Secondary
50/60 or 50/50 slow
and 60 Power Valve

Does this guidance apply regardless of what year Aisan carb we are talking about?

RicardoJM
12-27-2012, 01:51 PM
What jets do you currently have?

The recommended starting place for jets at higher elevation (according to Jim C and tested by myself and Ricardo) are:

112 or 114 Primary
180 Secondary
50/60 or 50/50 slow
and 60 Power Valve

Does this guidance apply regardless of what year Aisan carb we are talking about?

No the guidance should not be applied without taking into account year. The jetting (in Martin's post) is for the two barrel carbs that were originally on F engines in 1974 down to late 1969. Beginining with the 2f (1975 and on up) the jets are larger in the early "F engine" Aisan carbs.

While the guidance is a good starting point for these early carbs, each engine will have its own sweet spot. For example, the Blue Mule started out with an F engine and ran great with a Jim C. rebuild and when Air Randy swapped the F for a rebuilt 2F, the jet sweet spot changed. When we put in a larger primary it really woke that engine up. :D

spectre6000
12-27-2012, 01:52 PM
No. Depends on your setup. FYI, I'm waiting on a call back from Cruiser Parts. It sounds like they have a good variety and supply of jets. Unfortunately, they got some nasty weather and have a skeleton crew today so the guy that will REALLY know is not available. I also ordered some jet gauges and reams yesterday to make up for not having a buddy I see regularly with a set. I'll let you know how each end goes and see what I can do for that carb tuning writeup discussed on Mud.