924Board.org

[skytrooper]

Hey, I just picked up a '81 924 turbo. When it is running it leaves a small puddle of oil at the right front side near the cross member. It also is idling pretty high. Supposedly the turbo is not working...I'll get to that soon enough. The clutch peddle is weird, if you start to depress it...it will creep to the floor and stay there...is that a master or slave cylinder problem ?

[Paul]

The turbo is in the lower front right corner, the slave cylinder is on the back of the bell housing near the starter...

Turbo bad...may be leaking oil.

The clutch master and or the clutch slave cylinders may be leaking, bleed the clutch and see what happens.

The clutch peddle has a spring to assist the driver in pushing down the peddle.
_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

[johnathan1]

Not sure about the oil leak...

But for the clutch...check to make sure the fluid isn't low...probably a leaking master/slave.
_________________
-1977 924, 4-Spd...Gone
-1987 Toyota Supra Turbo, Pearl White, BPU, 300RWHP @ 10psi.
-1989 Mercedes-Benz 300SEL

WARNING: MAY CONTAIN TRACES OF AUDI OR VW!

[gohim]

You need to change both the slave and the master clutch cylinders. When one is dead, the other is dying.

[924guy]

try bleeding the slave cylinder before you go nuts on replacing everything. it has a bleed fitting right on it.. in my experience the slave fails twice as often as the master, generally due to rebuilt s being installed.
as for the oil leak, in that area you have several pipe connections, i would first check the oil cooler lines, and above that where there are several potential oil leak spots, and try and locate the exact source of the leak before starting a turbo rebuild. even if your turbo is bad, you could have another issue that contributed to failure like an oil leak to a feed line or oil cooler line, and should correct that prior to replacing the turbo, or during the turbo r&r so it doesn't happen again.
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[gohim]

And don't forget to change the timing belt first, since the 931 is an interference engine like the 944 and 924S.

You don't want ad to your problems by bending the valves.

[skytrooper]

[Zuffen]

The reason the slaves fail more often than master is the slave is the lowest point in the hydraulic clutch and brake system and water pools there.

The slave and master bodies are cast metal and very cheap. They rust and pit out very easily.

There is no rebuilt for the slave. At one time you could buy a 928 rebuild kit, news seals and spring.

The best long term approach is to always do the 2 year fluid change especially for the clutch.

The oil pooling under the turbo is more than likely a bad o-ring seal on the bottom return line. 2 13 mm bolts hold it on., the o-ring is a porsche part unless you know where to source high heat nitrile o-rings You can easily inspect that for proof of oil leak.

Before assuming the turbo is locked up you need to rev the engine listen for turbo whine check and also for any vacuum line leakage and including the bypass line control. Buy a cheap boost gauge and T it into one of the vacuum lines. Rev the engine and see if you see a bump in manifold pressure. Also listen for turbo whine (spooling). Sometime the wastegate can get stuck open.


If you are really handy and feel like you can get to the 10 mm bolts on the housing you can remove the front of the turbo while it is on the car. It is tough and sometimes impossible to reach each bolt. But the housing will rotate.

If they had reversed the bolt to the outside it would be so much nicer.

You can take the housing off and check your turbo for spinning by hand and check for axial play.
_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[Smoothie]

Whoops - the clutch slave seal kit is still available. I've been getting them from partsamerica.com the last few times. They have them at about $15. Just rebuilt one and popped it in today in fact - that and my once-a-year starter solenoid cleaning got done.
http://www.partsamerica.com/productdetail.aspx?MfrCode=TRQ&MfrPartNumber=CSK103545&PartType=237&PTSet=A
_________________
"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[Zuffen]

they were twice that from porsche, when they made them. we never rebuilt them...I have box of them somewhere as I never tossed them. I planed to sleeve them with brass and make them last longer.
_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[skytrooper]

Yup, slave cylinder was messed up pretty bad. So much fluid going through the seal that it was dripping out of the starter flange drain hole.
The bore looks great though so I will get a rebuild kit.
_________________
Matt

1987 - 924S "Black Pearl"
1982 - BMW 633CSi
1984 - BMW 528e
1983 - 944 N/A "Blue Max" (Gone)
1981 - 931 "Scarlet Harlot" (Gone)
1976 911S Targa (Gone)

[Smoothie]

Here's what I do at this point to make life easier and simplify the bleed process..
Cap the line where it attaches to the slave until you're ready to reinstall the rebuilt part. Empty the brake fluid reservoir (or the seperate clutch fluid reservoir for anyone with a RHD car). I use a Mityvac and a seperate container for this - a line sealed to the container lid has its' other end placed in the brake fluid reservoir, and the mityvac is attached to another hole in the containers' lid and used to draw a vacuum on it. _This pulls the brake fluid into the container without drawing it into the mityvac.
Refill the reservoir with fresh fluid and cap it.

Once the slave cyl is rebuilt, bench bleed it to fill it with brake fluid and expel all air bubbles. Use the cap from a transmission oil bottle as a small funnel, cut off to fit and screw into the slaves' line attachment port.
Get the line attachment threaded on and just slightly tightened - so it can be swiveled some. Position the slaves' rod into the end of the clutch fork and push it in, and attach and tighten the 2 slave mounting bolts. (As the slave is pushed into position, the rod is pushed in, and that pushes fluid from the slave up the line, removing most of the air.) Give the line attachment a final tightening. Check the fluid level.
Then just pump the clutch pedal by hand quickly until you feel it start to develop some resistance. At that point, continue pumping, but now pump it only a bit into the resistance instead of all the way to the floor. When the pedal starts to return on its' own, get in and pump it by foot another 10 or so times and you're done - no need to crawl under to bleed it in the usual way.
_________________
"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[skytrooper]

Thanks Smoothie, That should save me a lot of time !

>S<
_________________
Matt

1987 - 924S "Black Pearl"
1982 - BMW 633CSi
1984 - BMW 528e
1983 - 944 N/A "Blue Max" (Gone)
1981 - 931 "Scarlet Harlot" (Gone)
1976 911S Targa (Gone)