I broke my carb! HELP! (1 Viewer)

[BackFromTheDead]

As the title says, I broke the stock carb on my 85 FJ60.

It was idling rough and with low vacuum, and my mechanic said I had "dirt in the carb". He suggested I try to take the top of the carb off and clean it out, before jumping into a pricey rebuild or replacement.

I did just that - first replaced the secondary diaphragm. Road-tested it, and everything was fine, but still idling rough. I then removed the top of the carb, cleaned out the primary and secondary assemblies with carb cleaner on a clean rag, replaced the gasket, reconnected all the hoses, etc., and fired her up.

She started, hesitated, then stalled. Re-started, and she barely sputter, with heavy gas, she barely idled up, and then sputtered some more and stalled out.

Checking the carb after this, gas was dripping out of the carb off the secondary diaphragm and also the small pump to the right of the secondary diaphragm, near the bottom of the carb.

I removed the top of the carb again, checked everything, and put back together, and had the same problem.

Any idea what the heck I did wrong???

 

[2mbb]

You pulled the carb off the truck and removed the top on the bench or did you try to remove the top with the carb installed. My guess is that you did not get the needle valve and float installed correctly. Besides the seat, the needle valve has the main valve (three sided and pointed on one end. The other end is drilled and inside this goes a little spring and another small metal plunger.

Is the fuel 1/2 way up the sight glass on the front, or is the bowl filling all the way up?

 

[hank14]

The small pump at the bottom of the carb facing away from the vavle cover is the slow cut valve. The rubber boot around it was probably already deteriorated. There's a way to bypass it- you can find that info searching here. The assembly procedure is detailed in the 2F Engine Factory Service Manual. You might want a copy of that before you try tearing into it again.

And, rebuilding it it not much more complicated than taking the top off, if you can keep it clean, go slowly to make sure it goes back together right, and blow all the air passages out.

 

[BackFromTheDead]

Thanks guys - and 2mbb, thanks for the picks and your thoughts on what went wrong. I think you're exactly right, so I'm going to try to correctly assemble the needle valve/float right now.

It's hard to tell from the pic - is the needle valve/float part # 21301?

 

[2mbb]

part 21301 is the needle valve with the seat and the sealing washer (sub-part 21618). Part 21209 is the float.

 

[BackFromTheDead]

Well, 2mbb - I ruined it! Lost the spring and tiny plunger when taking the top off - sure to be found when I kick it up this spring with my lawn mower somewhere on my front lawn.

In any case, a Jim C. rebuild was long overdue, so I yanked the whole thing off and am sending it out Monday. Thanks again for your advice, and Jim - can't wait to see your work!