Intake leak
-
jwm5575
Intake leak
I could use some good advice on an intake leak. I have put the intake on a professional rebuild for the third time. The builder didn't put anything the first time. I had low vacum, so I put the carb cleaner to the intake, and I had a leak the top of the manifold. I pulled the intake, and the builder for plane, I think that's the right word. No problem with that. I bought another gasket , and was advised to use shellac. I hate shellac, so I used permatex black heat resistant silicone on all surfaces. It still leaked. I called the techs at Permatex, and asked them what they would do. They suggested I make my own gasket out of heat resistant rubberized gasket material, and use Hylomar. They said that was the right product for the application. I have nineteen inches of vacum, but when I really hold the carb cleaner on it , I still have a small leak. I am concerned about the wearing threads at this point. It's a 78 Spider by the way. IDEAS would be greatly appreciated. JWM
-
majicwrench
Re: Intake leak
Silicone will fail if exposed to fuel or gas fumes. DO NOT USE SILICONE on fuel/intake systems.
If you are spraying intake with carb cleaner and ilde is going up or improving, is likely cause the carb is suckingin fumes, not from some leak at intake to head.
The kind of flat, multi-bolt/stud arrangment fiat uses for intake to head is almost never going to leak. If indeed it has a tiny leak, so what, an engine is basicly one big vacuum leak anyway. "Really hold the carb cleaner on it"" is way too much. Fumes going everywhere if you are doing that. Engine is sucking in fumes thru carb.
Engine vacuum, or lack of it, does not neccessarly point to a intake or vacuum leak.
What sort of running issues are you having ?? Methinks you are chasing ghosts.
Keith
If you are spraying intake with carb cleaner and ilde is going up or improving, is likely cause the carb is suckingin fumes, not from some leak at intake to head.
The kind of flat, multi-bolt/stud arrangment fiat uses for intake to head is almost never going to leak. If indeed it has a tiny leak, so what, an engine is basicly one big vacuum leak anyway. "Really hold the carb cleaner on it"" is way too much. Fumes going everywhere if you are doing that. Engine is sucking in fumes thru carb.
Engine vacuum, or lack of it, does not neccessarly point to a intake or vacuum leak.
What sort of running issues are you having ?? Methinks you are chasing ghosts.
Keith