Question about power brake boosters

348tripower · April 09, 2008, 06:26:37 AM

I have a single diaphragm 9 inch booster. I am having a vacuum leak issue. Can one of these have a slight leak and still work? When I plug the line to this my engine smooths out like it should, but when it is hooked up and under load at idle it is really rough.
In my opinion a booster should work or not work, no in between.
Also should I pull vacuum for this from the carb base or the manifold. I assume that both places should work being manifold vacuum at both.
Thanks,
Don

tomslik · April 09, 2008, 07:21:41 AM

Quote from: "348tripower"I have a single diaphragm 9 inch booster. I am having a vacuum leak issue. Can one of these have a slight leak and still work? When I plug the line to this my engine smooths out like it should, but when it is hooked up and under load at idle it is really rough.
In my opinion a booster should work or not work, no in between.
Also should I pull vacuum for this from the carb base or the manifold. I assume that both places should work being manifold vacuum at both.
Thanks,
Don

yeah, they'll leak and still work and either place will work for the vacuum IF they have enough volume (as in a big hole,like 3/8")
sounds like you are on the right track..

348tripower · April 09, 2008, 08:42:56 AM

Quote from: "tomslik"
Quote from: "348tripower"I have a single diaphragm 9 inch booster. I am having a vacuum leak issue. Can one of these have a slight leak and still work? When I plug the line to this my engine smooths out like it should, but when it is hooked up and under load at idle it is really rough.
In my opinion a booster should work or not work, no in between.
Also should I pull vacuum for this from the carb base or the manifold. I assume that both places should work being manifold vacuum at both.
Thanks,
Don

yeah, they'll leak and still work and either place will work for the vacuum IF they have enough volume (as in a big hole,like 3/8")
sounds like you are on the right track..

Thanks for the let down this morning. :cry: I really believe that is the problem. I have not been able to get this to idle correctly from the start! I did plug the line and go for a ride last night. It idled really smooth with out the booster hooked up. Guess I have to order a new one.