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tuurbo · Posted: Sat Apr 26, 2008 7:27 am Post subject: Burning a bit of oil

Burning a bit of oil here when I hit the gas at idle.

Engine rebuilt in fall of last year. Need to change out 10W30 to 20W50 soon.

Haven't adjusted the valves since rebuild - going to do that first. Is that the possible culprit?

Rings might be going too but the engine was just rebuilt so I'd like to pursue the least costly guess first. If I rule out valves then rings are next culprit.

Compression test scheduled for after the valves adjusted, if that's a good idea.

Maybe there's room for another on that lawn tractor!

Thanks!
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1980 924 turbo, MSD, Meth. Inj, otherwise stock.

Smoothie · Posted: Sat Apr 26, 2008 12:45 pm Post subject:

No, valves being out-of-adjustment wouldn't cause oil burning. Bad valve seals and/or bad valve guides (more likely bad seals) would. -But one would assume that those things would have been addressed during the rebuild..?
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"..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

tuurbo · Posted: Sat Apr 26, 2008 12:51 pm Post subject:

Yes the head was rebuilt with new guides. I'll do your test of valve seals - downhill with engine braking correct?

The valve seals you mean are the 'valve stem seals' in the manual? Can they be replaced without removing the head?

There is some gas smell in the oil too.

Timing is correct now and the flywheel marked so I can repeat it and see it.
Mixture is set up so no missing.
Idle screw in almost all the way.

Smoothie · Posted: Sat Apr 26, 2008 12:59 pm Post subject:

That was Paul's cue to say "Change your oil!", but I'll say it this time.

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"..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

blackhat · Posted: Sat Apr 26, 2008 11:07 pm Post subject:

[quote="tuurbo"]Yes the head was rebuilt with new guides. I'll do your test of valve seals - downhill with engine braking correct?

The valve seals you mean are the 'valve stem seals' in the manual? Can they be replaced without removing the head?
quote]

I'm curious about these two questions two.

I'm trying to do just get it running as best I can with out doing a complete rebuild yet (saving that for the winter).

I've got the head gasket on the way but they where going to sell me a head gasket kit that came with the valve seals and I told them to hold of on that one 'cause of $$$. I figured I'd just change the head gasket and worry about those when I do the rebuild.

Should I change them when I pull the head off for the head gasket swap?

What's the down hill engine brake test to test the valve seals?

Anything else that should be changed while the head is off that doesn't cost an arm and a leg and could wait till the complete rebuild?
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My First Porsche
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1978 Porsche 924 N/A

tuurbo · Posted: Sat Apr 26, 2008 11:41 pm Post subject:

The oil's been changed now and I'm looking around the site for a procedure to replace the seals...

046 109 675 A Valve stem seal
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1980 924 turbo, MSD, Meth. Inj, otherwise stock.

Paul · Posted: Sat Apr 26, 2008 11:53 pm Post subject:

http://www.924board.org/viewtopic.php?t=25264&highlight=valve+seals+replacement
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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.

tuurbo · Posted: Sun Apr 27, 2008 12:31 am Post subject:

I hope that valve spring compressor puppy comes with an instruction manual!

Volkswagen Tool Number VW541/1

All I need now is the amazing Ronco SPECIAL tool 3047!

I guess the guy who did the rebuild didn't read that section of the manual that said Valve stem seals must always be replaced.
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1980 924 turbo, MSD, Meth. Inj, otherwise stock.

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Your rebuilder really didn't change them with the head disassembled? Are you sure?

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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

tuurbo · Posted: Sun Apr 27, 2008 1:05 am Post subject:

I can only guess Rasta. It fits with his past work habits. I also don't have anything showing he bought them, and I didn't get billed for them.

I could phone and ask him, but I don't trust his answer.

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1980 924 turbo, MSD, Meth. Inj, otherwise stock.

Paul · Posted: Sun Apr 27, 2008 1:13 am Post subject:

If he installed new guides there is no way he would have installed the old valve seals since they are usually destroyed during removal. Every cylinder head gasket set I have bought included new valve seals.
_________________
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.

Paul · Posted: Sun Apr 27, 2008 1:15 am Post subject:

Time to check your intake tract for oil to see if the oil is coming from the turbo.
_________________
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.

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Check your intake tract for oil. . .turbo seal leak seems most likely, and that will make you puff a bit on startup.
_________________
Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Paul · Posted: Sun Apr 27, 2008 1:19 am Post subject:

[quote="blackhat"]