mlwagar

I finally fixed the problem I had posted earlier, and now I noticed that after the car warms up to operating temperature I get blueish white smoke out of the tailpipe. The higher I rev the motor, the more I get. At idle there is barely a trace of smoke, and before it reaches operating temperature there is no smoke even if I rev the motor up. I checked the oil dip stick and there is no signs of water mixing in or frothing. The coolant level is remaining constant and the motor dosen't overheat and boil over. Could it be any other problems and does driving it under these conditions cause dammage to the motor? The motor is a remanufactured motor with about 9,000 miles on the clock.

Thanks for the help,
Mark... <img src="confused.gif" border="0">

Water944t

It sounds like a combination of things.

Mostly it sounds like turbo blow-by. Mostly.

The oil thins out when it gets hot. What kind of oil are you using? I reduced my blow-by significantly by going back to dino. I ran a good flush through to wash out the synthetic, and then 2 fills of dino. I am using the QuakerState High Mileage stuff, it has seal additives that make the seals swell back up. It stopped all my minor leaks, and reduced my blow-by as well. ( I actually think this is because I am running 50 weight, rather than the 30 I had before.)

What does it smell like, oil or coolant? I get some smoke at WOT from my sloppy-*** bearings in my turbo, but it always smells like oil. The boost just shoves it through. But I dont get all that much in my pipes, so it might be more valve seals. Fun Fun Fun. I cannnot wait to move (less than a month now) to AZ, finally no more carport. Gonna strip the engine down big time, full rebuild, top and bottom, and turbo. And maybe SEM, dont tell my wife. LOL!

It could be anything from a broken spring, to a head gasket. Valve seals, water seals, turbo seals, and I am sure I missed a dozen more.

The more info you give the board, the better diagnostics you will get.

<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

mlwagar

[quote] Mostly it sounds like turbo blow-by. Mostly.

<hr></blockquote>
The turbo is a brand new T04E Garrett. In regards to the smell of the smoke, it smells like oil, no trace of coolant. There was no trace of smoke until the car shut down in the middle of driving about a week ago. The cause of the shut down turned out to be the rotor set screw backing out and the rotor spinning around and getting wedged about 180 degrees out. When ever I tried to crank it over, while trying to diagnose the problem, it would obviously not fire, and would occasionally backfire alittle. Now the car runs fine. It starts smooth and stays running smooth. The smoke dosen't start until the car is at running temp (after the fans cycle once). The smoke at around 4500 RPM is pretty thick, but only after it is warm. While it is idleing, there is barely a trace of smoke. If I do have to change the head gasket is it harder than changing out the turbo I just recently did? Should I get a widefire ring head gasket?

Thanks,Mark.... <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />

951TFROG

[quote]Originally posted by mlwagar:
<strong>
The turbo is a brand new T04E Garrett. In regards to the smell of the smoke, it smells like oil, no trace of coolant. There was no trace of smoke until the car shut down in the middle of driving about a week ago. The cause of the shut down turned out to be the rotor set screw backing out and the rotor spinning around and getting wedged about 180 degrees out. When ever I tried to crank it over, while trying to diagnose the problem, it would obviously not fire, and would occasionally backfire alittle. Now the car runs fine. It starts smooth and stays running smooth. The smoke dosen't start until the car is at running temp (after the fans cycle once). The smoke at around 4500 RPM is pretty thick, but only after it is warm. While it is idleing, there is barely a trace of smoke. If I do have to change the head gasket is it harder than changing out the turbo I just recently did? Should I get a widefire ring head gasket?

Thanks,Mark.... <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" /> </strong><hr></blockquote>

Again, this DOES sound more like TURBO , and not a like head gasket !

If it was your head Gasket YOU WOULD KNOW IT !
Once it is blown, the car does not run properly, at iddle or at any speed ...
smoke is deep white, not blue....and you have got your own private smoke machine, so you cant forget it !

Also you consume water: if you water level is stable ,and you do not have water /oil mix IT IS NOT THE GASKET.For traces of water check the OIL CAP, and the water CAP, both of them would show a mix a of new kind....

Lastly: When changing a head gasket (it's a real job, the first time around) don't forget to ask yourself why you blew the gasket:Injectors,fuel pump, spark plugs they all tell a story if you listen carefully.....

By the way it is not, because it's suppose to be NEW, that all is alright, with your TURBO, but it could be a WEALTH of other things....

Good Luck

Eric

Perry 951

Easiest check for bad seals in the turbo is to pull an IC pipe and see how much oil is in there. To smoke heavily, you need a good amount of oil in there. Did you have the intercooler flushed when you rebuilt the motor?

I am leaning towards valve seats/seals being your problem. Once the car is hot enough, it starts to burn the oil and smoke. Running some oil additives to help seat the seals wouldn't hurt.

You could also do a leak down on it. This can pinpoint if it is seals, rings, or head gaskets.

mlwagar

Olli Snellman

What you described suits well to the symptoms when you have bad valve stem seals.Since you have only 9000 on your engine, it's odd..I repaird recently one 951 valve stem seals which were popped off a little from their place.It causes smoking when engine get hot.That car has about 20000km's on those seals.

Olli
'88 951

Olli Snellman

One more thing.Do not use too thin oil.Our cars were designed "pre-synthetic" era.I and most of my fellow 951 owners here in Finland use 20W50 mineral oils.

Olli
'88 951

mlwagar

I just ran a compression test this morning and here is the results:

1st #2 88psi
2nd #4 91psi
3rd #3 100psi
4th #1 96psi
Cylinder 2 (#4) & 4 (#1) both had some oil residue on the spark plugs, the other two were clean other than some carbon on them.
I ran the test after I warmed the car up to operating temp. and pulled all the plugs out. The throttle was on the floor. I also ran a second test with no appreciable difference in the numbers. I then ran a third run with a teaspoon of oil in each cylinder to test the rings (even though the motor only has 9,000 miles on the clock) and had no appreciable difference. I also ran a pressure test on the coolant system twice (to see if the system held pressure or forced water into the cyclinders) both time the system held for 5min. at 16lbs. and no drop what so ever. I checked the turbo to IC pipe and it only has the standard slight residue in them. I also checked the turbine outlet (downpipe) for any signs of oil there, but found nothing. THe motor still run smooth and only smoke after it warms up and is reved up above 3,500 rpm. There is no signs of oil mixing with coolant. Any other suggestions?

Thanks,Mark... <img src="confused.gif" border="0">

howie

I'm having a problem that it very much like yours. It also only smokes after it warms up. Them it will smoke at idle for about 5 min. After 5 min smoke goes away. Car never misses a beat even during the 5 min's that it is smoking. Also, no coolent loss???? Any ideas

Toolmaster

Ack...

Those compression numbers are a smidge low. Across the board too, leading me to think that it's a valve stem seal problem, or worse, like bad rings.

I'd do a real leakdown test to see what's up. there's a chance the head gasker is in fact toast, but it's almost non-likely due to low compression on ALL cyls.

Do a leakdown, and let us know those numbers, k?

HTH!

Olli Snellman

Check out valve guides & steam seals.Your car behaves excately like the car with bad valve guides or valve steam seals.
Steam seals are easy to replace, no need to remove head.

Olli
'88 951

<a href="http://www.p-caronline.com/directory/olli/" target="_blank">http://www.p-caronline.com/directory/olli/</a>

emilysgranny

Correct me if I'm wrong but the compression should be in the 140-145 psi range on the turbo.You are way to low on that. I agree with Perry ,no oil in the ic pipes ,chances are very good your turbo is good. When you added oil to the cyl and did the comp check and it made no difference I would rule out bad rings.Now the question becomes what did they remanufacture, just the lower end and not the head.I suspect your valves are not seated correctly and are the reason for the low comp check and the seals and guides are bad for the smoke problem as was pointed out. Just my .02 $ HTH

mlwagar

I just got finished replaceing the valve seals to see if that was the problem. While putting everything back togther, I noticed that one of my fuel lines had cracked from pulling the fuel rail back out of the way. I ordered some new stainless braided lines from SFR today and should have them in tomorrow. With any luck the smoke issue was just the valve seals. My theory is that when the rotor had spun free while driving a few weeks back, the ignition either advanced or retarded and ignited the fuel when one of the intake valves was opening. The premature or late ignition may have ruptured or forced the valve seal off its seat. The rotor had rotated almost 180 degrees out and the car subsequently died. I will let you know how it turns out when I can start the car.
Thanks for the help everyone... <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
Mark...

Olli Snellman

[quote]I repaird recently one 951 valve stem seals which were popped off a little from their place.It causes smoking when engine get hot.That car has about 20000km's on those seals. <hr></blockquote>

Have heard that for some reason these stem seals does not stay where they should.I ahve seen two different kind of seals fitted on 951's.I suppose Porsche changed the design due of these problems.

Olli
'88 951