How to fix your oil cap from leaking [Merged 3-8] leak leaky

[underdogTSI]

OK, my oil cap seems to leak, and when I take it off with the motor running, it shoots alot of air out, I also had that dip stick problem where it always pops out. I have bent the dip stick tube enough to keep it in there and put in a new pvc but nothing has stopped this...Anybody have this problem or solution?? Thanks.

 

[Batmobile]

bend up the caps...I think I'll try that out first....

yeah..replacing the cap was done already month or so ago....and now it's started again.

 

[fanatic26]

Whenever I go on a spirited drive, my motor seems to spit oil out of the fill cap on top of the valve cover. I messed around with an STi on the way home yesterday and sure enough, I check at the gas station and I have about 6 capfuls of oil puddled in the recessed part of the valve cover. I have changed the oil cap with one frmo the local junker and it didnt seem to help any. Is there anything else I can do to check this out? Synthetic is not cheap and losing it this way is a pain.

 

[steve]

Three things you can do.

1. Replace the cap or the gasket with a new one. The gasket gets hard over time and doesn't seal.
2. Check your PCV valve to make sure it's sealing and keeping boost pressure from pressurizing the valve cover/crankcase and pushing the oil out.
3. Perform a leakdown test to see if you have excessive blowby again pressurizing the block.

Steve

 

[diablos991]

Mine was leaking as well. MD311638 is the part number for the oil cap gasket. I bought one from Mitsu the other day for like $1.68 i think.

 

[fanatic26]

thanks for the quick responses, I will order a new gasket in the morning!

 

[nfernotalon]

I bought a new oil cap from auto zone and it was worse than my stock one, it sprayed oil even more!! So one of my buddy's said just bend the metal tabs on the inside!!! DUHH!! Just bend the metal tabs on the inside towards the inside of the cap, problem solved!!

 

[Gstclipse69]

Thanks for the info, been through a couple oil caps myself having the same problem. Ill have to try that

 

[cfue60]

I pull the gasket from the autozone cap and put it on the stock cap. I also bend the tabs on the stock one to put more pressure on the gasket.

Ciro

 

[NN4S]

New sealing rings for the oil cap are available from the dealer for under a buck; that's all I've ever needed to get the leak to go away.

 

[JBDdsmer610]

ok i recently put a new motor in my car i have been having problems with the oil cap leaking. I put 3 bran new oil caps on it already and they still leak my pcv is good i just cant figure out what else it could be .

Mods are in my profile

 

[drewvr4]

try a different valve cover, the breather in it could be plugged

 

[turbosax2]

http://www.dsmtuners.com/forums/bol...ged-9-7-cap-gasket-dipstick-leaking-pool.html

 

[ktmrider]

New oil caps including the gasket? You can replace just the gasket ( solved my oil leak issue ). Also how are you sure the PCV is good?
Last check to make sure the vent tube is hooked up to the intake, this also helps evacuate excess pressure in the head.

 

[JBDdsmer610]

try a different valve cover, the breather in it could be plugged

Yea i was thinking of that.... If my pcv is still good i guess its the valve cover. And yes the tube is hooked up to the intake.

 

[fwspin]

GASKET, GASKET, GASKET I can't say that enough I had the same exact problem with more than one DSM.

 

[bmoha2]

I bought a pretty expensive aftermarket oil cap that is billet aluminum. Looks great! Doesn't seal worth a crap. It has always leaked and peed oil into the spark plug well. There is nothing wrong with the valve cover. No cracks etc. It isn't that the oil cap doesn't seal tightly. It does...at first. The spring on the underside of the oil cap is really cheaply made and has no spring to it. Just a crappy design and piss poor execution of it's design if you ask me.It was fairy expensive and still looks good so I made a reinforcement spring out of a SS fork that is thin enough to have a little flex. The wife always hated those forks anyways.

 

[bmoha2]

and it leaked more than the crappy stock crappy plastic oil cap. Adding more or a thinker gasket to it didn't help as it would just force the crappy underspring to deform more. I cut the reinforcement part out of the fork with a Dremel tool. I replaced the screw that holds it all together with a longer one that I locktited in and also used a locking washer. I took the car for a beat down run and after wards there was no leakage. The top of the valve cover was as bone dry as when I cleaned it before reinstalling the now fixed oil cap. The oil cap is not old and has a rubber gasket on the underside of it that is in good condition. The oil cap now fits snugly but not too tight so there isn't any worry of metal shavings etc.

 

[Lurker]

I like your creativity of turning common objects ( e.g. forks ) into fabricated car parts

 

[bmoha2]

What til the wife tells the ladies at work about this one! Haha Soon they'll be calling me rubberband man. I've done other similarly bizarre things but have forgotten or even knew how to post of pics of the progress.

 

[Boost92awd]

I'm having the same problem as you have gone through a couple oil caps and they still leak. I guess the evo oil caps work great on are cars.

 

[Anonymity]

my cap leaked like it wasnt even there. all i did was double gasket it and i havent had any leak at all, a little hard to open now but it works

 

[bmoha2]

I put a tiny little flat washer behind it to fit it just perfectly I already had tried the double gasket thing.

 

[DGajre777]

Been there done that!

After having a Greddy oil cap leak on me, I went with an EVO oil cap.

 

[blcknspo0ln]

You guys do know that the OEM caps come with a rubber Oring right? My guesses are that these don't come with them?

p.s., 710 cap FTW!!

 

[bmoha2]

It's recessed into the underside of the cap. The gasket itself seems fine. Not too hard. No cracks, etc. The way the cap was originally setup, with it's spring just doesn't hold it tight enough to the valve cover, after it deforms the first time you put it on. Crappy design. The spring should be made out of spring steel or thicker stock. I'd say the bent steel that the stock spring is made out of is only maybe 32 of an inch thick and low quality low carbon steel.
It's a joke. I was very careful that when I modified my valve cap like I did, that it retained a stock like spring pressure holding it against the underside of the valve cover. I realize that the oil cap does not need huge amounts of spring force to hold it on. Too tight and it would damage, crack or scrape and deform the softer aluminum material of the valve cover. So in effect I spent no more money than I originally did ($35 plus shipping), I used a fork from my bachelor days that the wife hates and came away with a perfectly functioning oil cap that's nice looking and now actually works right. It just cost me a little time. Me? I kinda hate to buy a thing twice. When I bought the car it had a leaky oil cap. I bought a stock brand new replacement oil cap from the dealership and it did exactly the same thing. I took off the valve cover and closely inspected it, looking for a reason cracks etc, but found the valve cover to be intact and in perfect working order. I bought a fancy dancy expensive oil cap hoping to fix the problem and it in fact worked worse than the stock replacement (which also leaked.) I'm kinda surprised that more guys haven't run into this problem with these oil caps.
I bought it years ago thru MachV. I'm not knocking MachV. They were my first source for DSM tuning info. A great place to learn. They don't have a forum anymore. A lot of us guys that were listed as fanatics at MachV had to come over to this forum. The oil caps were pretty popular. Quite a few of us bought them. Practically all of us had similar problems with them. Seeping oil cap. Maybe I'm one of a few who actually kept a seeping oil cap for maybe 9 years. A sucker is born every day.