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cbmontgo
04-04-2008, 02:32 PM
Guys,

As some of you know, I am moving up to Colorado from Texas this summer and have an FJ60 with the stock Aisin carb. Do I need to swap the jets when I get to Colorado or does the carb automatically adjust for the altitude? I have heard that the HAC valve does this, but I want to make sure before I get up there and can't drive over 20 MPH!

Thanks,

Carson

subzali
04-04-2008, 02:43 PM
Don't know for certain, but my gut feel is that the HAC will do most of the work. I'm not sure any FJ60 is spec'd as a "high-altitude" spec around here.

cbmontgo
04-04-2008, 02:55 PM
Don't know for certain, but my gut feel is that the HAC will do most of the work. I'm not sure any FJ60 is spec'd as a "high-altitude" spec around here.

That is good to hear. We lived in Denver when I was a kid and moved to Mississippi and the old school carbureted Volvo we had never ran right down there. This made me wonder about the 60...

MDH33
04-04-2008, 03:29 PM
You won't do much better than 20mph on the hills here in ANY 60, regardless of the carb settings. :lmao:

I had my 60 carb rebuilt by JimC (TLC performance) and he asked about elevation and said he would set it up accordingly. Not sure what he did.

Main concern with bringing your 60 here is making sure it will pass emissions.

You'll get used to slow lane.:thumb:

Man Jerk
04-04-2008, 05:32 PM
If you wagon is in good tune, and the High Altitude Compensation (HAC) is complete and functioning, there should be no reason to change the jets.

Advance the timing a little bit and enjoy. :)

cbmontgo
04-04-2008, 08:05 PM
Sounds good; thanks for the info.

I expected to be in the slow lane anyway!

cbmontgo
04-10-2008, 04:40 PM
You won't do much better than 20mph on the hills here in ANY 60, regardless of the carb settings. :lmao:

Main concern with bringing your 60 here is making sure it will pass emissions.

You'll get used to slow lane.:thumb:

Speaking of passing emissions, does Colorado have an age cutoff for emissions exemption? I think it is 25 years here.

nuclearlemon
04-10-2008, 04:44 PM
Speaking of passing emissions, does Colorado have an age cutoff for emissions exemption? I think it is 25 years here.

yep, 25 here if you buy collector's plates, but you will have to pass emissions before you can get the plates:rolleyes:

60wag
04-10-2008, 07:16 PM
I looked at the CO dept of Rev website and found that vehicles 25 years and older qualify for collector plates but on the emissions pages, the vehicles exempted didn't include collectors plated vehicles. Also on the emissions page, they still have 1982 as the cutoff for the 2 speed tail pipe test vs. the RM240 dyno test. Are you sure that there is a 25 year limit on emissions?

cbmontgo
04-10-2008, 07:55 PM
This is interesting. I do think mine will pass emissions, but what happens if it does not? Mine is an '85, so I've got a little longer before it hits the 25 mark.

All of my emissions stuff is still there; I have even replaced a few things. I'll just have to wait and see what happens.

Thanks for the input--

subzali
04-10-2008, 08:57 PM
If it has good power, doesn't stink, doesn't backfire, etc. then there's a good chance it will pass emissions. If it doesn't then look into the different tricks like alcohol in the tank etc. I think you get three tries within a period of time to get it to pass so you start playing with things until they work. If you drive it regularly and it passes emissions where you are then you probably have nothing to worry about.

corsair23
04-11-2008, 12:11 AM
I looked at the CO dept of Rev website and found that vehicles 25 years and older qualify for collector plates but on the emissions pages, the vehicles exempted didn't include collectors plated vehicles. Also on the emissions page, they still have 1982 as the cutoff for the 2 speed tail pipe test vs. the RM240 dyno test. Are you sure that there is a 25 year limit on emissions?

I was under the impression with the collector plates you still have to pass emissions but only every 5 years :confused: - I've never gotten to the 5 yr mark so I don't know. I do know I had to pass emissions first before even going to the DMV to get the collector plates. I know the plates/registration are good for 5 yrs (all fee paid in advance), just not sure on the emissions.

Oh, and IIRC there is still that "sticky issue" about exactly how much driving you really are supposed to be doing with collector plates.

corsair23
04-11-2008, 12:13 AM
This is interesting. I do think mine will pass emissions, but what happens if it does not? Mine is an '85, so I've got a little longer before it hits the 25 mark.

All of my emissions stuff is still there; I have even replaced a few things. I'll just have to wait and see what happens.

Thanks for the input--

The trick for me back when in my '82 SR5 PU after it failed was to take it out on the highway for a nice long drive (WOT at times) to "carb it out" and get it nice and hot. Breezed the emissions test after that. Since then whenver I go in to get an older vehicle tested I do the same thing and I haven't failed again yet.

subzali
04-11-2008, 08:47 AM
Once you get collector plates then you don't have to pass emissions again, unless you let the registration lapse.

And the mileage thing - I doubt very many cops know or care about that, but I think you're right technically you're not supposed to drive it very much (don't know the frequency or miles/year), but my friend and others in this club I know DD these trucks, so...

MDH33
04-11-2008, 08:57 AM
Once you get collector plates then you don't have to pass emissions again, unless you let the registration lapse.

And the mileage thing - I doubt very many cops know or care about that, but I think you're right technically you're not supposed to drive it very much (don't know the frequency or miles/year), but my friend and others in this club I know DD these trucks, so...

Edit: Collector plates are not an option for your 60 as it's not old enough. but getting it to pass emissions shouldn't be too hard either.

As mentioned, you don't have to pass emissions again after getting collector plates unless A. you let the registration lapse, or B. you sell the vehicle.

The tricks that have worked well for me are running the engine long and getting it up to temp, like Jeff mentioned. Also run the fuel tank to almost empty and add a bottle of Heet (alcohol) like Matt mentioned. Doesn't hurt to have your engine running well anyway. Good luck, hope to see another 60 in the club. :thumb:

cbmontgo
04-11-2008, 11:11 AM
Thanks, everybody. I am looking forward to running with this crew!

BreckBJ44
04-24-2008, 04:37 PM
Just so you guys know about the HAC, It only helps in a small window. If I remember correctly (I sold my 60 years ago) it starts out helping at around 3500 feet and is at full open at 4500 feet.

Either way, when you get here just adjust the idle mixture to run optimally here and know that you will be rich or lean depending on where you drive.

I live at 10500 feet and set my carb at around 8500 since I was driving from Denver to Breck a lot. Rich up here and a bit lean in Denver.

HTH

cbmontgo
04-24-2008, 05:56 PM
Just so you guys know about the HAC, It only helps in a small window. If I remember correctly (I sold my 60 years ago) it starts out helping at around 3500 feet and is at full open at 4500 feet.

Either way, when you get here just adjust the idle mixture to run optimally here and know that you will be rich or lean depending on where you drive.

I live at 10500 feet and set my carb at around 8500 since I was driving from Denver to Breck a lot. Rich up here and a bit lean in Denver.

HTH

What exactly do I need to change/adjust if the HAC doesn't take care of it? Is there a screw that controls the idle mixture? I rebuilt the stock carb myself in 2006, but I returned everything back to the original setting and don't recall where/what that is. I just hope my rig doesn't run like crap when I get up there.

Thanks for the post though...

BreckBJ44
04-28-2008, 04:16 PM
There are two screws that affect idle mixture and idle speed. The most important is idle mixture. It will set where the carburetor begins with both air and fuel amounts when it begins to increase both (when you push the pedal) according to the manufacturers design.

The Idle Mixture screw is located on the engine side of the carburetor and is positioned at a 45 degree angle upwards. Turning the screw in leans and out richens. Take care not to tighten the screw in too much as it is essentially a needle valve and you can damage the tip. IIRC the stock setting is to start out at 2.5 turns out from full in (again be careful). You will need to take the AC (air cleaner) off to really get at this. You can do it by just moving the top cover, but be careful of the fan!

Run the truck to warm, then begin to open the screw. Try 1/2 to 1/4 turns first and let the carb adjust. You are looking for more revs with each revolution of the screw. Once the revs stop increasing with your turns, adjust the idle speed screw so you are back around 6-700 rmp at idle. Do this again until you don't see any more increase in rpm with adjustment. When I did it, I had to start the truck at 1.5 turns out since I was setting it for 10,000 feet above sea level.

The Idle Speed screw is located on the rearward side of the carb and points away from the engine.It is on the bottom side and you will need a long shank phillips to get at it.

Let me know if you have questions or want some help when you get out here.

Kraig

cbmontgo
04-29-2008, 08:45 AM
There are two screws that affect idle mixture and idle speed. The most important is idle mixture. It will set where the carburetor begins with both air and fuel amounts when it begins to increase both (when you push the pedal) according to the manufacturers design.

The Idle Mixture screw is located on the engine side of the carburetor and is positioned at a 45 degree angle upwards. Turning the screw in leans and out richens. Take care not to tighten the screw in too much as it is essentially a needle valve and you can damage the tip. IIRC the stock setting is to start out at 2.5 turns out from full in (again be careful). You will need to take the AC (air cleaner) off to really get at this. You can do it by just moving the top cover, but be careful of the fan!

Run the truck to warm, then begin to open the screw. Try 1/2 to 1/4 turns first and let the carb adjust. You are looking for more revs with each revolution of the screw. Once the revs stop increasing with your turns, adjust the idle speed screw so you are back around 6-700 rmp at idle. Do this again until you don't see any more increase in rpm with adjustment. When I did it, I had to start the truck at 1.5 turns out since I was setting it for 10,000 feet above sea level.

The Idle Speed screw is located on the rearward side of the carb and points away from the engine.It is on the bottom side and you will need a long shank phillips to get at it.

Let me know if you have questions or want some help when you get out here.

Kraig

Thanks, Kraig! I may take you up on that when I get to Denver.

wesintl
04-29-2008, 10:46 AM
high altitude adjustment :lmao:

cbmontgo
04-29-2008, 11:07 AM
high altitude adjustment :lmao:

Ha! Not a bad idea. Think a 2F could handle that?

wesintl
04-29-2008, 11:18 AM
Yep... If I had a 2f I'd certainly be tinkering. It would probably be better to add a FI but it can be done with a thru system and carb.

corsair23
05-05-2008, 02:03 AM
Yep... If I had a 2f I'd certainly be tinkering. It would probably be better to add a FI but it can be done with a thru system and carb.

Wes, anytime you want to tinker on a 2F I've got one in the garage you can tinker with :hill:

cbmontgo
06-09-2008, 10:12 PM
Hey guys,

The FJ60 and I rolled into Denver yesterday around 6 PM, and she ran perfectly all the way from Dallas. I was impressed...we crossed Raton Pass in New Mexico at about 7,800' and the rig still had plenty of power and did fine. I think this either means that the HAC works well or no major carb adjustment is needed.

And to top it all, it also got 17 MPG on the trip. I still do not understand how that was possible.

See y'all soon.

Carson

Uncle Ben
06-09-2008, 10:30 PM
Hey guys,

The FJ60 and I rolled into Denver yesterday around 6 PM, and she ran perfectly all the way from Dallas. I was impressed...we crossed Raton Pass in New Mexico at about 7,800' and the rig still had plenty of power and did fine. I think this either means that the HAC works well or no major carb adjustment is needed.

And to top it all, it also got 17 MPG on the trip. I still do not understand how that was possible.

See y'all soon.

Carson

Awesome...Welcome Carson!

MDH33
06-10-2008, 08:54 AM
And to top it all, it also got 17 MPG on the trip. I still do not understand how that was possible.



Glad you made the trip ok.

If you really are getting 17, I'm jealous. The best I got with my totally stock 60 in fine tune was 16 on the highway.

cbmontgo
06-12-2008, 09:27 AM
Thanks, guys. We are glad to be here. Closing on the house today and the movers show up on Sunday...this cool weather is awesome compared to Dallas!

wesintl
06-12-2008, 09:31 AM
I know what you mean. First summer we didn't use the AC at all unless it was over 95. Now it goes on sooner but the cool nights lately have been nice.

Congrats Carson!

cbmontgo
07-13-2008, 02:08 PM
Guys,

Here's a tidbit of information I wanted to add into this thread regarding high altitude and the stock FJ60 carb.

I just got back today from taking my son camping up towards Argentine Pass. It is VERY cool; we had a blast. The FJ60 did great all the way up to Waldorf Mine, but suddenly SHUT OFF at the treeline (around 12,000') just above it. It did fine all the way up to that point. I wonder if this altitude is where the HAC valve stops compensating? I even rolled back down a hundred feet or so and restarted the engine and took a less steep trail. It did it again, like clockwork, and the same altitude. My guess is that some adjustment is needed if I want to wheel at that altitude.

I ran into Subzali on the trail today; that was very cool!

Anyway, we camped out at about 11,500' and drove back today. Great trip...the new sign looks great, by the way...

Carson

subzali
07-14-2008, 08:12 AM
Hey Carson, very cool to see you in person finally! We ended up going all the way up to the pass, which is almost 13,000 feet, with no problems, my vintage of carb doesn't have HAC, so it's all jet settings...

Anyway, with some checks of vacuum, engine speed, etc. versus idle speed mixture and the other adjustments on the carb, you should be able to get your carb dialed in so it runs like a champ, even at altitude! And if you have the FSM just double check to make sure the HAC diaphragm is working properly too! And remember to check your air cleaner, spark plugs, and all that good stuff, reason tells me all that makes a bigger difference at altitude! :thumb:

cbmontgo
07-14-2008, 04:18 PM
Hey Carson, very cool to see you in person finally! We ended up going all the way up to the pass, which is almost 13,000 feet, with no problems, I'm not sure if my vintage of carb has the HAC, I don't think it does, but there is a diaphragm on it that I'm not sure what it does...

Anyway, with some checks of vacuum, engine speed, etc. versus idle speed mixture and the other adjustments on the carb, you should be able to get your carb dialed in so it runs like a champ, even at altitude! And if you have the FSM just double check to make sure the HAC diaphragm is working properly too! And remember to check your air cleaner, spark plugs, and all that good stuff, reason tells me all that makes a bigger difference at altitude! :thumb:

Thanks, Matt. It was awesome to catch up on the trail. I'll start doing some tinkering with my carb and see what I can come up with.

subzali
07-14-2008, 04:43 PM
Careful! cause if it ain't broke...

cbmontgo
07-14-2008, 09:19 PM
Careful! cause if it ain't broke...

Yeah, I know. I rebuilt it 2 years ago and it runs great. Maybe I should just keep her below 12,000 feet and be happy!

subzali
07-14-2008, 11:03 PM
I just noticed on my 22R-E that a tuneup is suggested if/when changing altitude. It wouldn't hurt to do one IMO, and just do some checks without messing with stuff just to make sure it's all working right :thumb: