Pop-off Valve Popping Question

[clnilsen]

OK, I searched the archieves, and I can't quite find an answer.

In my normally functioning 1980 SC, last week I installed a Pop-off valve. The car has run fine for years, no problem whatsoever. Just somepreventitive maintence I am gettin around to.

Well, now it seems when I start the car cold, there's a horrible amount of poping from that thing for the first 2-3 min. Is this normal? As I said, the car ran great and no issues were known to be beforehand.

Thanks!

Chuck

[ruf-porsche]

you may have a vacuum leak. remove the air cleaner, start the engine and spray a little carb cleaner around the popoff valve. If the engine speeds up you have a vacuum leak. Put some more epoxy glue where the popoff valve meets the airbox, wait until the glue is completely dry befor starting the engine, you don't want to suck epoxy down the manifold into the engine.

[Doug Zielke]

Be sure to lid on your valve has an o-ring.
The first one I bought, was shipped without one!

[clnilsen]

OK, I tried the Carb cleaner idea around the pop-off valve, and no change in engine RPM..

Any other ideas on what may be causeing teh start-up issues?

Thanks!

Chuck

[Garyo4]

Did you drill the hole for the pop-off valve when the airbox was in the car? If so, are you sure the pilot drill didn't put a hole into anthing underneath the airbox that it shouldn't have?

Best of luck,
Gary

[IROC]

Didn't some of the later CIS cars have the cold start plumbing in the air box right below the area where the pop valve installs? Could you have inadvertently hit the cold start plumbing?

Mike

[clnilsen]

Yeah, I did do it in the car, but I don't think the pilot went though. I took the bit out as soon as the hole saw cut in to avoid that..

hmm..


Chuck