turbo oil suply

[MarcHogenboom]

Gentlemen, I just installed a Garrett GT 35 Turbo and oil lines on my engine. I made the suply line and the return line the same diameter( 4mm). Now I see a little oil dripping from the bypass valve axle. Could it be that the pressure in the turbo bearing is getting to high because of the small return? Shoud I make it a wider one?

[JohnC]

Originally posted by Marc Hogenboom:
Gentlemen, I just installed a Garrett GT 35 Turbo and oil lines on my engine. I made the suply line and the return line the same diameter( 4mm). Now I see a little oil dripping from the bypass valve axle. Could it be that the pressure in the turbo bearing is getting to high because of the small return? Shoud I make it a wider one? In a word, yes!

Make it as big as you can. I'd go 5/8-3/4" (15-20mm). The seals in a turbo cannot stop any pressure and rely on the drain back to keep oil from accumulating behind them. (Ask me how I know this!)

[MarcHogenboom]

How do you know this?

Thanks JohnC, ill change it.

[JohnC]

Originally posted by Marc Hogenboom:
How do you know this?That was rhetorical, but, since you ask, I made the same mistake back around 1968 on a gas engine. Boy, did it smoke!