Fj60 Rough Idle - Ignition Problem? (1 Viewer)

[nutsaboutsoccer]

I just finished putting the 2F engine back together on a 1985 FJ60 that I just purchased. This think had a blown head gasket and had sat for 5 years. Valve job on the head and rebuilt carburetor. New plugs, wires, rotor, cap.
The things seems to run okay, but idle is a little rough and can't set it below 900 rpm. When I pull individual spark plug wires to check for miss, the thing still idles at 900 rpm with either (or both) #1 or #2 plug wires disconnected.
Compression is good (140-150) on all cylinders and the spark plugs out of #1 and #2 look to be burning normal.
Any Ideas?
Thanks,
Ted

 

[ellington12]

no rpm change even with no spark to 2 cylinders? that's very strange; usually that indicates that those cylinders aren't doing anything.

i think i'd double and triple check for vacuum leaks and check all of your carb linkage to make sure that the the idle stop is actually resting on the idle stop screw. make sure your fast idle linkage is adjusted correctly as well.

did you by chance have the fuel tank and lines flushed out at some point? 5 years of sitting can be hard on the internals of your tank.

the lack of rpm change when inducing two dead cylinders is very strange and has me a bit stumped...

 

[nutsaboutsoccer]

Gas tank was removed and cleaned, fuel lines flushed and new filter installed. Carb linkage is fine. Haven't found any vacuum leaks.
I cannot figure out why disconnecting plug wires from cylinders 1 and 2 doesn't affect the idle speed. I'm stumped too!!!

 

[cando john]

vacume leak? @intake/head between 1&2 just a guess?

 

[rover67]

make sure the idle jet/screw in the carb is clean and clear.... remove the screw and blow compressed air through it.

may have poo in it after the rebuild or the fuel system.