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andyfranqueira · Joined: 06 Aug 2005 Posts: 61

Question. I'm getting a little smoke from the front of the engine around startup. Doesn't last long and doesn't seem to be a major problem. Any ideas?

leadfoot · Posted: Sun Aug 14, 2005 1:22 pm Post subject:

Is this only occuring when the car is cold?? If it is then you may have a slight exhaust leak from the manifold, either at the head or at the join to the manifold downpipe.
The smell of oil burning may be related but it will give the smoke a bluish colour whereas steam/whitsmoke tends to be water vapour or coolant, coolant will also smell distinctly sweet. Check you coolant levels in the expansion tank to make sure your levels arn't dropping off quickly.
The best thing I can suggest is to give your engine a clean with some degreaser and then run your car up to operating temperature with the belly pan of the car. This will allow you to see if your leaking oil/coolant from somwhere and allow you to track it down easily. Cover all your electrical parts like alternator and distributor and coil etc.. before you rinse of the degreaser with water. Allow to dry and warm up the engine, and check at 1 minute intervals for leaks. By the way put a drop sheet down when you do this unless you want oil on your driveway.
Common places for leaks are oil filter seals, camshaft cover seals, coolant temperature and oil pressure senders/sensors at the back of the head.
If you find oil pooling at the bottom of the starter motor then these will be places you should look, as they tend to splash near the exhaust downpipe and make a real big smell.
Leadfoot
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

andyfranqueira · Joined: 06 Aug 2005 Posts: 61

Is blue, I guess it's an oil leak? Seems to be below the alternator?

leadfoot · Posted: Sun Aug 14, 2005 2:40 pm Post subject:

Won't be your alternator... the brown cylinder looking thing is probably your engine vibration damper siting between the starter motor and alternator and will not be the cause.
Oil leaks tend to flow quite definately and you wil see signs of this if you get under the car and take a look up towards the manifold. Most obvious is checking the oil filter for leaks, if you have the right angle adaptor for the oil filter there is also a seal between it and the block which can leak profusely when it's cracked and old. It will also pool at the bottom of the filter and starter motor shrouding. If it makes its way onto the shrouding then look at this seal.
The only other way it's going to get near the manifold is if the headgasket is leaking, and a surefire way of telling this is that your car runs really rough and your coolant and oil have signs of depositing in each other.
You would also see smoke coming out the back of the exhaust both blue and white quite thickly and constantly. Sounds like you've got a minor oil leak in need of attention.
Leadfoot
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

andyfranqueira · Joined: 06 Aug 2005 Posts: 61

Cheers

Smoothie · Posted: Fri Sep 02, 2005 6:28 pm Post subject:

That could be just a leaky oil filler cap.
_________________
"..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

andyfranqueira · Joined: 06 Aug 2005 Posts: 61

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

It would help if you mention the model and year of you car when you are asking for advise.

In your case, people have been giving advise based on the idea that your car is a 924, and NOT A 924S.

The 2.5L engine in the 924S is complete different from those in the 924 and 931.

The leak that you are describing could be coming from the paper gasket that fits between the cylinder head and the cam tower assembly. Many people don't realize that the valves on a 924S/944 engine are housed in a separate housing (cam tower), located above the cylinder head. To replace the paper gasket, the timing belt must be removed, as well as the cam tower assembly, if the leak is from the paper gasket, you should perform the complete front of engine service, since the belts have to come off anyway.

The leak that you have noticed could also be from the front of the engine. If the leak is from the front of the engine, replacement of the timing and balance shaft belts is immediately necessary, as they will be suffering from accellerating deterioration. Motor oil and it's contaminates eats the belts. For this reason, the front of engine oil seals are normally replaced as part of a complete front of engine service.

The front of engine service must be performed every 30K miles or three years (whichever comes first). It includes replacement of the timing and balance shaft belts, front of engine oil seals, ball bearing equipped rollers, and pulleys, and the waterpump. The cost runs between $1500-$2500 depending on where you buy the parts, and who you have do the labor. A competent shadetree mechanic can do this service, but specialized tools costing $700-$800 dollars are required.

87 924S engines are known to suffer from an uncommonly high percentage of blown head gaskets between as early as 70K miles and 100K miles. The most common sign of this problem is brown scum in the coolant tank, and overheating.

Slam · Posted: Sat Sep 03, 2005 4:14 am Post subject:

Hi, Andy,

Guys, he's got a 924S.

I'll bet your cam box/cover gasket is leaking. It's about the only thing in that area that can leak oil onto the exhaust. Oh, and you're right about the brown reservoir - it's for the power steering fluid.

If your cam cover leaks (and I'll bet yours does) there's a kicker. To replace this gasket, you'll have to take the cam box off, and that'll require a timing belt/balance belt R&R.

So! If you don't know when your timing belts were last changed, consider this the Porsche gods' way of telling you to do them. If the belts were properly serviced and you've got proof, then live with the leak until it's front of engine service time. It's a big job, relatively speaking. Check out clark's garage (can't remember the web address - help, someone?) first. Read all you can about the timing belts - any lack of knowledge here will have a nasty ending.

HTH
_________________
'88 944 Auto - may or may not resurrect

andyfranqueira · Joined: 06 Aug 2005 Posts: 61

Slam · Posted: Sat Sep 03, 2005 6:44 am Post subject:

Gohim - we must have been typing at the same time!

Andy - yes, I read your sig...

gohim was describing the cam gasket, not the head gasket. And just because the engine was rebuilt doesn't mean the t-belts are okay. If it was a year ago I'd do them now and then know for sure what the service schedule is.
_________________
'88 944 Auto - may or may not resurrect

Lizard · Posted: Sat Sep 03, 2005 10:19 am Post subject:

it is refered to in all the literature to the Camshaft Housing gasket.
and if you dont KNOW 100% and have reciepts as to when the timing belt was last done, DO IT NOW, as well as the waterpump, and from the sounds of it all seals as well and the camshaft housing gasket at the same time, as you need to take the belt off to do that.
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3 928s,

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

It doesn't make any difference if the P.O. (previous owner) of the car claimed that the engine was recently rebuilt or recondition, immediately prior to your buying it or not.

The fact is that the engine is leaking. This fact does not generate any confidence in me as to the work that was supposedly just done. If the work was done completely, and correctly, why is the engine leaking already?

Find the leak immediately. If you don't have writtern documentation showing when and what work was done, you need to get the front of engine service done, SO YOU WILL KNOW when it was done, and when it will be due again.

If the front seals are bad, you need to get the belts replace PRONTO.

andyfranqueira · Joined: 06 Aug 2005 Posts: 61

Okay, the belt was replaced at the engine installation. I spoke to the mechanic and got a copy of the receipt. I even checked it myself and it looks good.

The leak is coming from the front of the cam housing and is tiny...

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

A leak from there is going to require removal of the timing belt.

This still means that you might as well do the "front of engine" service as you will need to remove both the balance shaft and timing belts to get in there, if you cannot positively confirm exactly what was replaced, the number of miles since the work was done, and the amount of time that has past.

My guess is that your "friend" cannot confirm exactly when she had the work done, and what was done. My guess would be that receipt that she has was for the "front of engine" service, and/or work to replace bent valves due to a broken belt.