FJ60 struggles to rev past 2500rpms

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@WartHog73 thanks for additional photos - super helpful.

From what I can tell it looks like the linkages + springs are reinstalled correctly.

Please see photos: first 3 are linkage and throttle 4th is on front of carb there is fuel dripping out of the butterfly stem (not sure what that is called).

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callmeahab said:
@WartHog73 thanks for additional photos - super helpful.

From what I can tell it looks like the linkages + springs are reinstalled correctly.

Please see photos: first 3 are linkage and throttle 4th is on front of carb there is fuel dripping out of the butterfly stem (not sure what that is called).

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Also note: the PO delinked the idle-up diaphragm and its connected idle screw (related to desmog, not sure) still the throttle worked fine w/o out that idle-up equip connected.
 
Another note: per my previous post I said that it struggles to rev past 2500k rpms in neutral and 1st-3rd gears, it started to rev "normal" in neutral well into 3.5-4k rpms now. So it does seem to be really under-load. WTF
 
CruiserTrash said:
Baseline first, otherwise you'll chase your tail. Like @MoaByte says: spark plugs, valve lash, timing, make sure the distributor advance diaphragm is working. Add to that a new air filter & oil change - amazing what those two can do to a truck that's been sitting. Replacing the fuel filter already was a good move. Follow the factory service manual for all of this. It's available for free under the "Resources" tab at the top of ih8mud. I'd also thoroughly verify the "desmog" work. Lots of people rip out a bunch of vac lines and call it good, but are really creating more problems. the factory Emissions service manual is your friend here.

Couple other questions: Do you have a catalytic converter? After all of the above is done, you may find the cat is plugged partially or fully. Baselining will help drivability in the long run anyway, so it's not wasted time. I'd also verify that your carb is sealing to the intake manifold properly, and that you don't have any leaks between the intake/exhaust manifolds and the head.
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Yes it does have a cat. I have tested for leaks w/ carb cleaner around the carb seat and hoses and there does not seem to be any that I can find.

Another person asked if it makes a whooshing sound when the gas cap is taken off - its make a sucking air sound.
 
callmeahab said:
Yes it does have a cat. I have tested for leaks w/ carb cleaner around the carb seat and hoses and there does not seem to be any that I can find.

Another person asked if it makes a whooshing sound when the gas cap is taken off - its make a sucking air sound.
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That’s a bad evap canister, but I can’t think of a way that would limit your engine revs. If the valve that purges the evap canister to the carb (to burn the captured fuel vapors) is broken, it would act as a vacuum leak though.

Edit: no it won’t.
 
I actually dreamed that the reason for my 60's sluggishness was because of the vacuum in the fuel tank! 😂😂. After fixing the canister (and replacing the carb with a Sniper) my sluggishness went away and my mpg got worse!
 
Does it still run rough?

Can’t tell from the pics if your carburetor rod is installed correctly or not, it looks like it might be, but please confirm.
 
klinetime574 said:
How does it idle though?

Have you checked timing?
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It idles rough and inconsistent - moves from 650rpms on start to 1krpms after warm-up, then stalls at stops.

I have not checked timing as I need to review how to do that. I will update.
 
MoaByte said:
How does the fuel level in the float bowl look?
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I'm glad you asked, After the carb rebuild it was middle of window but then went above the halfway mark and even flooded. Now there is no fuel in the window. I have checked the fuel line and fuel comes out when disconnected. Even though the fuel pump looks newish, I think I will replace.
 
callmeahab said:
I'm glad you asked, After the carb rebuild it was middle of window but then went above the halfway mark and even flooded. Now there is no fuel in the window. I have checked the fuel line and fuel comes out when disconnected. Even though the fuel pump looks newish, I think I will replace.
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Is the float adjusted properly? The pump might be fine, but if the float isn’t asking for fuel it ain’t gonna fill up the bowl.
 
Have you checked compression? Just to rule that part out. I may have missed that you checked that already, but if you haven't, you might want to before you go any further. Low compression on one or multiple cylinders can cause rough idle, stalling, and a general lack of power, especially under load. I know you are looking at fuel, and I don't want to sidetrack you. I just start with basics when I have a weird issue. Make sure that the basics are good before proceeding.
 
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callmeahab said:
I'm glad you asked, After the carb rebuild it was middle of window but then went above the halfway mark and even flooded. Now there is no fuel in the window. I have checked the fuel line and fuel comes out when disconnected. Even though the fuel pump looks newish, I think I will replace.
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I think you are close to fixing this.
 
callmeahab said:
I'm glad you asked, After the carb rebuild it was middle of window but then went above the halfway mark and even flooded. Now there is no fuel in the window. I have checked the fuel line and fuel comes out when disconnected. Even though the fuel pump looks newish, I think I will replace.
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Could be just the needle valve needs to be cleaned...
 
thabruiser said:
Have you checked compression? Just to rule that part out. I may have missed that you checked that already, but if you haven't, you might want to before you go any further. Low compression on one or multiple cylinders can cause rough idle, stalling, and a general lack of power, especially under load. I know you are looking at fuel, and I don't want to sidetrack you. I just start with basics when I have a weird issue. Make sure that the basics are good before proceeding.
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That is a good point. I have not checked compression. Just a note: only the 3rd cylinder spark plug had some carbon fouling. Before I had the card rebuilt (rough idling) it did pull quite strong with no power loss. I will add compression to the list and needs to be on the list anyway as it has 225,000 miles.
 
callmeahab said:
That is a good point. I have not checked compression. Just a note: only the 3rd cylinder spark plug had some carbon fouling. Before I had the card rebuilt (rough idling) it did pull quite strong with no power loss. I will add compression to the list and needs to be on the list anyway as it has 225,000 miles.
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Any news on your diagnosis? My 60 is running way too rich and I’m in the process of rebuilding the carb (again), and I ordered a new fuel pump in case the fuel return isn’t working and the float is being overwhelmed. Very interested in what you figure out.
 
RDub said:
Any news on your diagnosis? My 60 is running way too rich and I’m in the process of rebuilding the carb (again), and I ordered a new fuel pump in case the fuel return isn’t working and the float is being overwhelmed. Very interested in what you figure out.
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How do you know your 60 is running rich?
 
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