Thread: Need help to idle...

Tweet

Sounds like a vacuum leak - get a can of carb cleaner and with the engine running (a friend helps here), spray around the base of the carb and the area where the intake manifold meets the heads. Any change in speed indicates a vacuum leak.

Also - I think you may want to reconsider the PCV (Positive Crankcase Ventilation) setup. Unless your engine is real tight you'll be making a bit of a mess around where your breathers are located. The atmosphere inside the engine becomes more laden with oil vapor as the engine "ages" and tolerances grow. You need a breather to allow flow into the engine and the PCV then uses vacuum to literally suck that oil laden vapor into the intake stream where it's burned along with the fuel. If you don't use the PCV, make sure the inlet is well sealed

Good Luck,
Glenn

OK.... appears I have vacuum leaks between base plate and intake.

What carb gasket do y'all use to suck this up? Silicone OK here?

David

Originally Posted by Dsprint2000

OK.... appears I have vacuum leaks between base plate and intake.

What carb gasket do y'all use to suck this up? Silicone OK here?

David

I would use a straight edge and verify that the manifold isn't warped / twisted. You can use a thin film of silicone as long as it's not an oxygen sensing EFI system. Carb motor should be fine. Also - if it's a stock ford thermostatic type choke, you'll need that heat tube or replace it with an electricaly heated unit. Otherwise it'll take forever for the choke to open.