help fj40jim carb rebuild runs like crap now

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Please help. cruiser with an awsome carb rebuild by fj40jim won't idle

My 1984 fj 60 has suddenly developed over night a real problem. I think I have narrowed it down to the carburetor. It bucks and stumbles when coasting and does not want to stay running at idle. I had the carburetor rebuilt by fj40jim about a month ago and has been running really good until today. It kinda acts like the timing is retarded at idle but the timing light is showing the bb on the index. I posted earlier in my build thread about the choke but got no responses. I hope someone can give me some good advice because I don't feel confident enough to go messing with jims tune.
 
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It sounds dumb, but...is your idle cutoff solenoid plugged in? I managed to overlook that, myself, after replacing my manifold gasket, and spent an hour trying to figure out what was wrong.

Another thing I'd check is for leaks on the base of the carb, since that sounds like it might be a vac leak. The easy way to check is with a vacuum gauge, but you could also just check if the carb nuts are tight enough on all four corners.
 
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The idle cut off is still connected. I'll check the carburetor mounting nuts in the morning.
Thanks for the response.
 

orangefj45

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the thread title definetly leaves a lot to be desired.........

did you contact jim to see if he has any input for you. he's usually extremely helpful, nevermind extremely knowledgeable.

georg
 
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I'm not doubting jims work it runs really good at highway speeds and with my foot in it. I'm kind broke down right now and posting via my iPhone. Sorry should have took more time to post a better title. When I first talked to Jim he seemed really busy and swamped and with all the knowledge that he has passed on and with others knowledge here as well, I thought that I would try to do the easy fix first before bugging the man himself. Sorry again. Is this what is meant by jumping the cutoff selenoid, or do I need to do something different?

Thank you

Burl
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Carburetor mounting bolts were all tight as well. I also found out the the spring the tensions near the choke linkage was not allowing the choke to fully actuate. I think that's fixed.
 
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down in a hole.
check for vacuum leaks...can you hear an audible click at the carb(idle fuel solenoid)when the key is turned on? What is your idle speed? Are there any loose or disconnected vacuum lines. Is this problem present consistently or does the truck have to warm up before your problem presents itself?
 
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If all is well..vacuum-wise, base bolts-wise, cut off solenoid-wise and in general the carb area is functioning, for giggles I'd spend $10.00 and change the fuel filter and see what happens.
 
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Another thing I thought of:

For about 30 miles of driving after I did my manifold gasket (and had the carb off), my engine bucked and hesitated occasionally, because it took it that long to get all the little bubbles out of the fuel line. It smoothed out and didn't ever buck like that again.
 
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Is your truck completely de-smogged ? If so, jim told me that with a de-smogged system that the ground from the selenoid plug should be put to a constent ground... the way it is wired from the factory the ground goes to the computer and it gets a pulse ground... i don't remember wire colors, but if remember when i get home from work tonight i will post a pic of how i grounded mine...

This fixed the ruff idle and a tendency to studder at about 2200 rpm on my 60...

on a side note... You will probably not get a response from jim till next week sometime... he is part of a rally car team also and i know they have a race this weekend...

:cheers:
 

Trollhole

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Put your hand on the idle solenoid and turn the ignition to on. Do you hear or feel a click? DO this before you do anything else.

If it doesn't click you have a bad solenoid, or it's not grounded correctly or your fuse is blown.

Start with the easy stuff before you tear into it.
 
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I can hear a definately audible click in the engine compartment when I turn the key, but can't quite reach the fuel cut off selenoid when I turn the key to tell if it's actually coming from the selenoid itself. It sounds further away like near the starter but can't tell for sure.
 
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My rig is completely smog legal. I live near Fresno ca. It just past smog about 3 weeks ago with literally 0 emissions. The carburetor was installed a week before the smog with no adjustments after jims re-build. I had the fuel tank recall work done and replaced all the fuel lines and filter at the same time just before I got the carburetor back from Jim. I won't rule out the filter yet.
 
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Jacob, I don't have the emissions manual but, I think all the vacuum lines are correct, because I copied another guys system when I replaced all my lines before smogging. He copied his system from D'Animal, who is pretty savvy. My rig seemed to pass smog quite well with the setup I had. I think everything is good but, does anyone or you know the proper procedure for checking for a vacuum leak? I've heard wave an unlit propane torch near all the lines. Will a mity-vac pump work also and which lines should I test?
 

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