1970 fj carb issues (1 Viewer)

[SADDLEUP]

Hi all, new to this forum, and been lurking for a while.lol I have 1970 FJ40 Feb mfg, and cant get it to idle. I have replaced plugs, wires , distr.,.points carb kit, brake master cyl. new elec fuel pump and all new lines, incl vacuum lines, At 900 idle it sprays fuel thru the venturi in carb. i understand no fuel shud be misting in carb at an idle... correct. ? Have tried to adjust idle screw and air mix scew to no avail.. air mix does not seem to make much difference. Any ideas what i shud be looking at.... re do carb kit, vacuum leaks.... where to look. OR maybe issue is electronic?? Any /all suggestions welcomed.

tks from Alberta Canada

Bob

 

[SADDLEUP]

Hi all, new to this forum, and been lurking for a while.lol I have 1970 FJ40 Feb mfg, and cant get it to idle. I have replaced plugs, wires , distr.,.points carb kit, brake master cyl. new elec fuel pump and all new lines, incl vacuum lines, At 900 idle it sprays fuel thru the venturi in carb. i understand no fuel shud be misting in carb at an idle... correct. ? Have tried to adjust idle screw and air mix scew to no avail.. air mix does not seem to make much difference. Any ideas what i shud be looking at.... re do carb kit, vacuum leaks.... where to look. OR maybe issue is electronic?? Any /all suggestions welcomed.

tks from Alberta Canada

Bob

Any help?

 

[78Landcruiser]

sounds like u have done a bit of work to this truck in efforts to make it run properly,



how did the points install go? Dwell spec can be a bit tricky and what base timing did you set the distributor too?

while Rebuilding the carb did you blow clean all the tiny passages ?

if it’s only wanting to run/ idle off of the fuel from the primary fuel nozzle then I would highly suspect your ide circuit , how is your idle solenoid? a failed one would keep it from idling .

you also mentioned replacing the booster so I know u must be aware that a vac leak would also cause this, another place to check would be the manifold , and anything els plumbed to it,

many things will result in a poor idle,

post up some engine bay pics maybe some one can spot something,

 

[65swb45]

Second the idle circuit malfunction theory. Of course that begs the question of whether you have enough manifold vacuum to properly pull fuel through the idle circuit.

 

[SADDLEUP]

Second the idle circuit malfunction theory. Of course that begs the question of whether you have enough manifold vacuum to properly pull fuel through the idle circuit.

Sorry for late response, have cked vaccum steady at 14.5 , idle solenoid clk out seams to be working right. Points, rotor cap and distr cap replacement seemed normal. carb was what i thought to cleaned very well, and soaked overnite and cleaned thoroughly . Could a worn shafts inside carb be a possibility ?

 

[65swb45]

14.5” is insufficient to draw fuel through the idle circuit.

 

[Dizzy]

I recently bought a new PCV valve that seemed to allow much more air to pass to the manifold side than a new(ish) OEM PCV valve.

 

[thebigredrocker]

make sure your throttle cable has a tad bit of slack where it connects to the carb. so it's not holding the primary open.

 

[SADDLEUP]

make sure your throttle cable has a tad bit of slack where it connects to the carb. so it's not holding the primary open.

tks for heads up on cable slack will ck it out

 

[SADDLEUP]

I recently bought a new PCV valve that seemed to allow much more air to pass to the manifold side than a new(ish) OEM PCV valve.

New pcv, grommet and hose....

 

[SADDLEUP]

14.5” is insufficient to draw fuel through the idle circuit.

'tks for input, will recheck all vaccum lines again My elevation is 3500 ft if that will matter?

 

[Dizzy]

Thee Microguard PCV was bad in my assessment.

Yes, altitude matters.

I'm no carb expert, but I have less than 15 inches at 6,800'. I can Idle my 2F on the idle circuit (no gas from the nozzle) at 700 rpm.

 

[SADDLEUP]

Well Guys, i found the problem. the carb is worn out. The throttle shaft is allowing in air and creating the vaccum drop. Sprayed brake cleaner right on shaft an idle smooths out. Never got around to back side of carb as i am a bit mobility challenged (rotator cuffs) LOL NOW... the search for a new carb for a 1970 Feb model f engine. .. can anybody steer me in that direction Thanks for all the advise and help so far.. it is most appreciated

 

[John McVicker]

^^^
See post # 6 in this thread and contact Mark. He can get you running again.

 

[SADDLEUP]

^^^
See post # 6 in this thread and contact Mark. He can get you running again.

Tks will call Mark in morning .. appreciate the lead..

 

[4Cruisers]

My elevation is 3500 ft if that will matter?

See my Post #8 here:

Compression and Vacuum From Way Up Here

My 2F came to me with little history, besides knowing that the crank turns. I bought some Bosch tools at the auto store and tried them out today. I'm at 6,800' above sea level. I probably have used about ten gallons of gas since the engine was installed. Compression: #1=97 (wet=100) #2=102...

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