Weird oil leak during blts

[talon2gbuyer]

Hey all so I've run into a weird problem lately, while doing boost leak testing I have oil pissing out of the engine from somewhere. I can't pinpoint it for sure but it seems to be coming from somewhere under the car, but its pissing a lot, like I had the air supply hooked up for maybe a minute and there was easily a quart of oil on the ground. Any ideas?

 

[kchaazz]

Oil filter housing, turbo oil return line, and removing the timing cover to inspect the front main seal, oil pump shaft seal and balance shaft seal would be a good start. I thought I was going to do a boost leak test with the feed line for my turbo disconnected (was waiting on an adapter to hook it up) and oil pissed out of the feed line and was coming up the return line and coming out of the feed port on the center section of the turbo. Course, this was on a brand new motor that hadnt even been started yet, so there was definitely a lot of blowby past the rings and into the crankcase. There will always be some blowby, and when you add pressure when performing a blt, any place you might have a slight leak when the motor is running will piss like hell during a blt because the motor isnt running and the PCV system isnt working.

Oh, and one more thing, just so we are clear. This air supply of yours was regulated down to around 20- 25 psi right? You didnt put 100+ psi into your car I trust. If so, you likely blew oil out of your oil seals and may have damaged them.

 

[talon2gbuyer]

Found it. It was the turbo oil return line. The gasket on it was cracked all the way through, so now its RTV seal time.

 

[WES_393]

Dont use silicone sealant, replace it with a dry gasket.

 

[jpmxrider489]

Dont over do it with the rtv. Just use a generous amount.

 

[NHerron]

A generous amount would be considered excessive...

I use very little RTV on that gasket. Basically just enough to where you could wipe the gasket clean in one try. Like a film of RTV rather than a layer

*That goes for a new gasket, I wouldn't reuse one already damaged.

 

[kchaazz]

^^Indeed. Dont even try to use RTV instead of a gasket there, it will squeeze in and block the return passage and your turbo will die (Forced Performance has tons of pics of this failure). Use a gasket, and if you must, use the smallest amount of rtv possible, and the above poster suggested.

 

[talon2gbuyer]

yea im gonna pick up a new gasket tomorrow. Hopefully local parts store has one in stock (since they NEVER have our spark plugs in stock and i need to special order them.. :sigh: )

 

[boost97gst]

Possibly get a generic gasket of similiar size and use a scalpal to cut it to the proper dimensions. I mean, if you cant find the exact match.

 

[curt-s]

^ You can use one of these provided they're made of the proper material to use for oil gaskets. Most are fromall the do-it-yourself-gasket-kits I've seen; a couple of sheets of various types of gasket material for $7 or $8, and you can replace all sorts of gaskets. I use them when I don't want to keep buying OEM thermostat housing or J-pipe gaskets, with the lightest of skim coat of grey RTV just for extra measure.

For a oil return gasket, use a good quality gasket. The OEM ones are nice because they have that extra inlaid seal. Add a couple OEM crush washers, and you have a no-leak solution for $5.

If you can't wait, use DIY gasket material and practically no RTV. Don't forget that oil will also leak at the bolt holes, so you'll have to seal those too. Normally, I wouldn't suggest RTV for this, but that would be hypocritical as I have in the past. I just make sure to add so little that it will not impede the return line at all when sealed up to the pan.

 

[talon2gbuyer]

Extreme psi sells the oil return gasket for like $2.50 so I'm gonna grab one from them.

 

[BogusSVO]

If you want to use a sealer of some sort, Use non-harding form a gasket by permatex it is thin and applies with a "paint brush" This also work great for sticking a gasket in place that like to move.

It is not bulky like RTV, but is more like a thin tar, and will fill in small scratches and such. but will not block the oil return line.