FJ60 Carb: Altitude Adjustment
- Thread starter cbmontgo
- Start date
cbmontgo
Hard Core 4+
high altitude adjustment
Ha! Not a bad idea. Think a 2F could handle that?
wesintl
Moderator
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
cbmontgo
Hard Core 4+
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
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
Hard Core 4+
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
Hard Core 4+
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
Moderator
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!
Congrats Carson!
cbmontgo
Hard Core 4+
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
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
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!
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!
Last edited:
cbmontgo
Hard Core 4+
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!
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.
cbmontgo
Hard Core 4+
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!