Pop Off Valve Failure. Any suggestions for temporary roadside fixes?
 

Last week my pop off valve "popped off". Fortunately it only left me stranded around the corner from my house. The whole valve unseated and broke free from the epoxy. The valve was ok and looked new as no epoxy residue was attached. I realized my boo-boo when I saw this as I did not clean the valve off with alcohol and I did not roughen the surface that contacted the epoxy when I installed it almost a year ago. I must have omitted this step in my excitement and haste when the car was new to me at that time. The valve is back in after a proper second installation and lesson learned.

This got me thinking... "What if the pop off valve fails again and I am farther from home?" What can I do for a temporary fix to prevent the vacuum leak so the car will run? Yes I do have a AAA card so ultimately things should be ok if I have to get a tow.

Say the valve unseats again or the spring holding the flap brakes and can't maintain the seal (oh yes I did apply a little epoxy to the ends of the flap so the stem holding ths spring in place doesn't slide out).
Would plugging the hole with a tapered rubber stopper like the ones for those Ehrlenmyer flasks back in chemistry class work? If yes, think it is a good idea to carry one "just in case"?

Appreciate your thoughts and comments.

Popped Pop-Off.....
 

I had the same thing happen to my SC not long ago. I simply pushed the valve back into the hole (fortunately it was a tight fit) and went on about my business. Later that weekend, I bought some appropriate epoxy and glued it back into place. I suppose that one could make a couple of small metal brackets bent in a z shape and fastened with small self tapping screws to hold the pop-off valve in place. On the other hand, it happens so rarely, why worry about it?

Fred Cook
'80 911SC coupe

I had the same thing happen to me about 6 months ago. I just re-epoxied it back in place adding a little more epoxy than was on before and haven't had a problem since.

Yes I agree, this occurring is probably going to be rare. But with my luck if it ever happens again, it will probably happen on some really important day, so I was trying to think of an easy, temporary fix that could "save the day" if ever needed.

usually the hole the valve fits in is pretty snug. A temporary fix is to just jam it back in till you have time to re-epoxy it.

same thing with mine, so what's the story? all our valves are defective?

how come they never work like they're supposed to?


quick roadside fix: get a plastic bag, cut hole, and wedge between diameter of valve and hole in airbox.

i thing they all will do it and its not a "defect" as mentioned above. i think there is just not enough surface area on the airbox/valve contact area to be a forever deal. the temp fluctuation in the area probally is not any sort of ideal enviorment for epoxy.

i would think that the plastic bag idea would be costly as the bag melted from engine compartment heat.

since this 1st occurred on my car i check it every now and again.

a perfectly drilled hole will hold the valve nicely. just press the sucker back in.

Its held in by vacuum so it isn't coming out......unless you intake backfire!!!

It was a back fire that blew it off. Since I didn't install it right the first time, the bond between the epoxy and valve weakended over time and it blew off with a back fire.

Putting it back in didn't work as there was enough of an air leak that prevented a vacuum from forming. I tried a plastic bag in the hole, but could not create a tight seal.

The valve was ok, no defects. Hopefully now it is epoxyed in correctly now. Who knows, the epoxy may fail in a few years or in a few years if the spring is brittle , it may break after a backfire. For future I was thinking a rubber stopper may help for a temporary fix if it ever fails again.

Mine blew out recently also. Happened in my garage, so no big deal. I like the idea of a big rubber plug like that used in the erlenmeyer.

how about a toilet flapper from Home Depot:

http://www.homedepot.com/cmc_upload/...s/579509_3.jpg

pretty cheap!
:D

Actually it might not be a bad idea. Then parts would be interchangeable for two of my favorite places to sit!! :-)