Pop off valve woes.

Milo2361 · Milo2361's Garage

wow... never thought this would really happen but i went out to start my car about 5 minutes ago - - was gonna go for a drive, pick up some supplies from wal-mart, then bring her back to campus.... heres what happens.

first off its pretty dang cold right now - - in the 10s and below, so this may not have helped anything - - - but keep in mind i have started and driven it in colder!!! no problems.

anywho - i get in and turn it over - - it stumbles a little cause its cold then it turned off... this is normal - - so i cranked it again - - usually it fires right up on this 2nd try and maintains a higher idle cause its so F!^@ing cold out - - but instead of that happening i heared a little pop, and thought"oh my pop off valve is open now ok" so i opened the air box to look at it and the whole thing popped out of its hole

may this have caused damage to the engine? what sort of sticky substance do you recommend i glue it back in with?

i hope this isn't too serious because i have no where near the funds to make a big repair

edit: i also tried a quick search but it wouldnt use the word "off" so i decided to post! sorry if this has been posted before but it has me kinda worried

kmhemi · 02-03-2009, 05:08 PM

The same thing happened to me. I didnt get enough epoxy on it when I installed the pop off valve. It didnt hurt anything when it popped out. Just glue it back in and make sure you get a good bond. I put mine back in and havent had anymore problems since.

Zeke · 02-03-2009, 05:14 PM

A hardware store epoxy kit will get the valve back in nicely. You have to make sure all surfaces are really clean because you are dealing with plastic.

Now, for the not so good news: this may happen again. If you didn't slightly crack the intake manifold, you dodged a bullet. However, a leaky intake valve (or one too tight) will cause this to happen again. Or, you might just have a piece of carbon on the valve seat. A spirited drive should eliminate that possibility.

In any case, once you get the POV reinstalled, it's time for a go through. I'd bet there is no damage at this point unless the manifold has a crack. They can be sneaky to find.

At the risk of being flamed, I will offer you this: http://www.youtube.com/watch?v=4MVRXS5ILvI

ossiblue · 02-03-2009, 05:16 PM

kmhemi (and Milt, he posted while this was being typed) have the answer. Be sure to clean off all the old epoxy, and you should grind down the ridges on the floor of the box, right under the valve lip, if it hasn't been done. This will give you a flat surface to bond and guarantee a better seal.

rsscotty · 02-03-2009, 05:16 PM

I would reglue it in with JB Weld. I suggest the slow cure type rather than the 5 minute type. This is a two part epoxy you have to mix 50/50..Clean both the valve surfaces with 220 sandpaper to rough up the surfaces, brake clean, let dry, and apply the JB. Usually I let it set up overnight. Your outside temperature may be too cold for the JB, so read the instructions on that. You may also want to charge the battery so the engine cranks over good.

Before you apply the epoxy you may want to test fit the pop valve in the hole in the airbox. It should fit snug. The hinge part should go toward the rear of the car.

I have seen those valves come out before and have never seen any engine damage from it as long as nothing broke off the valve or airbox to get in the intake...so check those areas.

Hope this helps.

Cooper911SC · 02-03-2009, 05:22 PM

+1 on the JB. I used some other epoxy the first time around and it didn't like the plastic the airbox is made from, popped out after a few months...The JB has been in since 2001 with no problems.

Milo2361 · Milo2361's Garage

that's a pretty good feeling to know that its more than likely its just the valve being out... if there is some slight separation in the box is it still safe to drive? i dont think i really have the means here to take the whole thing off at my present location... lack of tools and space...

kmhemi · 02-03-2009, 06:06 PM

I used the JB QUICK weld on mine. works perfectly. as mentioned above, make sure everything is clean to ensure a good bond. Let us know how it turns out.

don gilbert · don gilbert's Garage

milo Ive put a lot of these in. as in a previous post above, i recommend grinding the fins all the way down and glue it in with urethane. (not silicon) it will never come out again and makes for a good tight seal. after they have popped out a few times and the old epoxy has been ground off a few time the suface is hard to get flush. Ive been using jb weld all my life, but ive had jb weld ones come loose (sometimes a year or two later) and you are stranded (no fun)

john walker's workshop · 02-03-2009, 06:19 PM

you need to rough up the surface of the valve so the epoxy can get a bite. very slick otherwise. i take it lightly to a wire wheel on a bench grinder. boat stores usually sell two part Hardman epoxy in paper packets. JB weld works ok. clean all surfaces with alcohol to get any oil off.

Danimal16 · 02-03-2009, 06:20 PM

+1 on the JB.

Milo2361 · Milo2361's Garage

well i wasn't able to take the airbox off(lack of proper garage) but i got all the old glue off ---came off almost all as one piece.... it fit right in and it solid! running great! - - whoever put the valve on previously didn't grind off the ribs though... might be a later project for me.

kmhemi · 02-10-2009, 02:42 AM

glad to hear thats all it was...