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RobDumoulin · Guest

Well, She Smokes, She Drinks, and She Runs Around on Me, but I still want to keep her. My turbo is dumping oil in the exhaust pipe. I know I have to replace the turbo anyway. What is the worst that could happen if I just cap the oil feed line to the Turbo? I'd be willing to sacrifice some performance to buy some time.

AznDrgn · Guest

I would think that eventually the turbo would cease making that turbo absolutely beyond repair and it might block your exhaust a bit. Other than that I don't see any other problems with killin the oil feed to the turbo.

John H · Guest

Correct me if I've got the wrong idea - you want to stop feeding oil into the turbo altogether.

If so - big mistake this will mean the turbo bearings get no oil and it will destroy itself big time and probably fairly quickly.
Not only will it destroy the turbo but depending upon what lets go you could destroy your motor as well.
When the turbo goes bang you could find bits from the compressor side flying through the manifold into the motor prior to either you or the motor itself shutting down.
(I've followed a 930 in a race when it's turbo let go and it did a power of damage - and it caught fire quite nicely - mind you he still had oil flowing to it)

Again I wouldn't recommend it.

Ants · Guest

If your going to replace your turbo, prices quoted are often for exchange (ie you give them your old servicable turbo) this is usually cheaper than buying one with exchanging it, therefore don't blow your turbo completely otherwise it won't be serviceable, this is sure to happen if you cut off the oil feed.

Ants

Rick MacLaren · Guest

Not meaning to alarm you, but, if your engine has lost oil, it might already be toast. Even a small depletion of oil to the turbo can cause wear. Once the oil is dirty, that dirt moves all through the system.

Any slightly loud valves making noise? 'Tick tick tick' coming from the head?

924RACR · Posted: Tue Dec 18, 2001 11:03 am Post subject:

Yeah, uh, the turbo kinda needs its oil, spinning at 50,000RPM or so at 1400 deg... that's why Porsche put an oil line to it.

Getting the oil feed lines to seal properly is a common problem, had this on my 931 when I got it... a real PITA, but not much cost in parts... R+R'ed it and replaced all seals and gaskets, etc... fixed!

Now the front main leaks! Doh! Oh well, at least that's a lot easier...

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

larso · Guest

Vaughan, which lines don't seal properly and how do you repair it? torque and special washers or is it something else?

924RACR · Posted: Wed Dec 19, 2001 8:19 am Post subject:

When I got the car, the oil feed line in the top of the turbo was the problem. There's like 4 seals in it. When I R+R'd the turbo to fix that, they then began leaking where they attach to the oil filter head. The replacement aluminium washers leaked like a sieve. Finally found the identical coppre washers that worked great first time. Sure took a lot of torque to seal, but don't overdo it - too much, and you'll snap the hollow bolts! Just enough to get the thing to seal with the engine running. Took a few tries, finally sorted it out on the lift.

Good luck

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Smoothie · Guest

I'd have to agree with those that say that intentionally starving the turbo of oil is too big of a risk. The turbo on my 931 died a slow natural death from old age several years ago. It went slowly and quietly (it apparently just got gunked up to the point that it stopped spinning). It didn't explode and break into a thousand pieces and didn't spread destruction throughout the rest of the engine - because it went slowly. If you just completely and suddenly cut off the oil supply, you may have an entirely different experience from mine. Anyway, once the turbo stops spinning (if it's intact) it becomes a major blockage to the intake airflow (and exhaust). Performance is r-e-a-l-l-y sad. In addition to the blocked airflow, you have the fact that the turbo engine has low compression. If the engine itself were high compression and you tried to run it with a turbo, you'd end up with too much compression and lots of detonation. Turbo engines are designed with low-compression because they're meant to run in concert with a turbo all the time. A 924 turbo engine with its' turbo frozen is a low compression 4 cylinder engine with blocked airflow - very sad indeed.

[ This Message was edited by: Smoothie on 2001-12-22 11:15 ]