1974 911 pop off valve question and troubleshooting tip
 

Hi,
A quick story of my experience and a question...

I was not able to drive my 911 much this year because work and life got in the way... Boo.. So I had not started it for about 6 weeks... When I tried, it would fire but not run and backfired a few times... Then it would not fire at all unless I let it sit for a few hours... Off I went down the spark and fuel troubleshooting road and I could not find any issues... I was into the air box a few times to see if there were issues there and the last time I found my pop off valve sitting in the air box... It had disconnected from the air box completely... I think the issues were with air leaking around the epoxy seal and finally it came apart... ( my car has always had a habit of backfiring if it did not catch on the first try... Usually it fires up at a touch of the key... ) ...

I am looking for a recommended epoxy to reseal it... I live in Canada so if you know a suitable product here let me know...

Also I am wondering if I need to completely clean the old epoxy away... The epoxy is well sealed to the air box but there is little or no epoxy on the pop off valve... The surfaces are smooth and clean on both parts... I would have thought it would bond into the pop off valve plastic ("melt it a bit" if that makes sense?)

All help appreciated... I figure it's the cars way of telling me to drive it more :)

Thanks...
Jon

JB Weld seems to be the popular fix.

http://www.jbweld.com/

Yes. And rough up the surfaces so it has something to grip.

The hinge side faces rearward.

And use a dental mirror to confirm a good fillet of cement on the back (invisible) side.

Think I have it....
 

Thanks for the replies... I spent some time roughing up the surfaces of both the air box and the valve...then some acetone to clean it up... Mixed up the JB weld and carefully coated the surfaces on the pop off valve that would make contact... Looks like I got a nice bead all the way around... Mirror was a help... Thanks for that... Tomorrow I'll fire it up and check it over...

Looks like $20 is going to fix what I thought might be much more...

Thanks for the fast replies...

Jon