smoking issue update.
 

Well..today, after searching this site and other places, I took of the intercooler to have a look.
My upstart smoke issue is still there, it seems to be less on start up when I rev it up to 3000 rpm's before I shut it down on previous use.

Just now, the car has not been in use for 13 hrs. I removed the intercooler and the first thing I saw was a streak of oil from the intercooler down into the turbo. The next thing I saw was approximately 1/2 teaspoon of oil in the throttlebody resting nicely on top of the throttle valve (????).

Can any wise soul tell me why I have oil in my intercooler?
Maybe the turbo is not the issue anyway then?

I will also add to the equation that this is really the first time I have been using the car since I bought it 1.5 years ago. I have recently used the car on a regular basis for a month and a half.

G

Is it a CIS car? Maybe oil from oil tank vent into air filter housing...?

A little oil in IC is normal, but not a teaspoon of

PS: if you have the stock drip tank for turbo, it's vented to air filter housing too, then there could also be a problem with scavenge pump

Thanks.

Also, as I had to get ready for work, I left the IC off. I left it on my nice tiled garage floor tilted with the thorottlebody connection corner as the lower part. When I took one of the other cars out of the garage 90 minutes later, i happened to have a look at the IC. Would You belive that at least 1/4 of cup of oil has leaked out from that thing? All over my nice floor.

Jeez....that cant be right??

G

+1 on what brian said leave the turbo rebuilding to the people that do it daily and well

No, a residue of oil is normal, a puddle means your seals are being breached.
Have you verified oil flow through the turbo and pump? With multiple turbo failures I would suspect oil flow is either too much or being blocked and backed up in the turbo.

Hoyo,

As usual our varied opinions and suggestions lead us to " If you throw enough sh-- against a wall some is bound to stick" I would respectfully suggest, before you run out and buy a new $1200 turbo or anything else, you step back, gather some facts, and then inspect and verify so you know what you are actually dealing with.

The turbo lag issue: We know the 7600 is going to have some inherent lag, but, we don't know what engine you really have, what cams are in the motor, what the cams are set at, what timing is set at, what intercooler your running, what exhaust system is on it, are you running CIS, and what the afr's look like.

The smoke on start up issue: Typically your turbo seals are leaking oil or the scavenge system is not up to par. Do you have the 9mm restrictor ball at the turbo inlet line banjo, are all the scavenge lines and drip tank clean and free of obstructions, is there any air intrusion in the suction circuit, is the scavenge pump evacuating properly.

I would suggest you deal with the smoking issue first. By doing so you can either fix the smoking issue by checking out the scavenge system and fixing any issues or, after ivestigation, determine you need to rebuild or replace the turbo. Once you have determined the turbo issue you can plan where you want to go from there.

If your going to replace the turbo, then, you want to sit down and decide exactly how you are going to use the car and what you want from it. Doing that will require knowing exactly what you have now. ( what engine you really have, what cams are in the motor, what the cams are set at, what timing is set at, what intercooler your running, what exhaust system is on it, are you running CIS, and what the afr's look like ) By using this type of approach you will end up with the car you want and make informed choices that get you the best bang for your bucks.

As you can tell from the reponses to your original post, we are all here to help if needed. Brian has forgotten more about these sleds than most of us know so your starting out in good hands.

Cole

"The "repack" would be the $89 "superior k27 turbo overhaul kit" from ebay. I think.....from what I was told by one of the po's.
The "overhauling" was done by a buddy who was in the posession of a screwdriver and a wrench."

I believe the rebuild kit you mention is a cheap low grade copy made in china and a total waste of money and time.

Good rebuilds of a K27 using origonal 3K borg warner parts followed with computerized high speed balancing of the cartridge assembly start around $500 if no extra machining is needed inside the bearing housing.

The rest has already been well covered.

Gentlemen.

Thank You for Your time.

I'm just back from work. I had to take a few pictures of the IC, oil puddle and the engine.

About the engine and how much/little I know about it.

It was sold to me as a 3.3Ltr. The engine number shows that it is a 1978 3.0 engine.
When I called Tony about that, he said the 3.3 had its block cracked. They then used the block of an 3.0 and put the internals from the 3.3 in the new block. New rings were put on in addition to a mild cam. This is what I have been told.
Twin plugged and headers in addition to the 7006 turbo are mounted. Electromotive ignition and what I believe to be the original fuel delivery system.

If it is so that it is a different cam and the larger turbo, for all I know, it might be that it is in fact a 3.0 ltr engine. The 3.0 turbo had 260 hp. With headers,7006 and cam I'm sure that 330 hp is not unreal on the 3.0.
I have not had the car tuned but will as soon as I have the smoke/oil issue sorted out.

I have not pulled the air filter for a looksee but will do so tomorrow morning. If it is clogged. Could that pull the oil from the engine and into the IC as mentioned in an earlier posting?

I will at the same time have look for that 9mm ball. The lines seems to be free and clean.

How do I verify oil flow through the turbo? From what I could tell with my limited knowledge of these fine machines, (keep in mind that I'm still a humble 928 driver) the oil in the turbo is visible from a fine stream coming down from the IC. As previously mentioned, I also found 1/2 tablespoon of oil right on top of the throttle body valve. Is it possible for oil to be backed up in the turbo all the way up and through the IC?

http://forums.pelicanparts.com/uploa...1305141899.jpg


http://forums.pelicanparts.com/uploa...1305141937.jpg


http://forums.pelicanparts.com/uploa...1305141971.jpg

Once again, I really appreciate the help.

Thats a lotta oil... and it's dirty. Looks like your motor is due for an oil change.

The oil gets blown into and through the intercooler in a mist with the air going through it so it will be everywhere downstream of the turbo compressor housing.
You will have to rinse out your Garretson long neck intercooler with about a gallon of mineral spirits to rinse it out.
Turn the intercooler upside down in a big tray, plug as many hoses with wadded up paper towels and pour in most of a gallon of mineral spirits and slosh it around and back and forth through the core. Then repeat with more clean mineral spirits because there is alot of oil in there and one rinse won't get it all out.

Then put the intercooler out in the hot sun to evaporate the remaining solvent. I like to put the intercooler upside down in a bathtub or set tub full of hot water and detergent after the solvent rinse to really clean it out good.
Then install it while still wet with water inside the core and just drive it for a while to dry the water out.

An oil coated intercooler core doesn't work well to cool off the hot air from the turbo. I don't consider any oil in the charge pipe or intercooler "normal". I have an old K27 7006 on my motor and the charge pipe and intercooler stays totally clean and dry of any oil film.

The brown staining on the WUR may be from a fuel leak.

Your air filter is a large K&N cone filter and it is dirty bit not real bad. I don't think thats causing any problems. Most likely your turbo is junk from what you've said and all the oil it's blowing.

Never seen a green o-ring on the throttle body before. They are usually a red color. Hopefully it's the right thickness and not leaking.

Describing the cam as a "mild cam" doesn't define anything. You have to find out whats actually in there. SC and 964 cams are the most popular upgrades when running CIS injection.

If your's has the black painted cast iron euro fuel head it will deliver around 10% more fuel during boost and high rpms over a stock '86 -'89 930 lambda fuel head.

Check the output section of the metering section. Look into the plenum area below the metering plate to see if there is any oil pooled below the metering plate. This will rule out any possibility of the engine sucking any oil out of the oil vent line connected to the air cleaner assembly.

Hoyo:

I have no idea how much you know about the scavenge system so please excuse
any excess information.

Start at the center rear of the engine you will find; The red switch sits on top of the banjo bolt that supplies inlet oil to the turbo.

http://forums.pelicanparts.com/uploa...1305145992.jpg

This is an exploded view of that assembly: Make sure all the parts are there and assembled correctly, especially the 9mm ball.


http://forums.pelicanparts.com/uploa...1305146168.jpg


The oil line will run to the front of the engine and connect to the turbo on top and between the turbo halves. This is what oils the turbo.

http://forums.pelicanparts.com/uploa...1305146702.jpg


Your drip tank then connects to the bottom center section of the turbo. The drip tank holds the oil as it flows through the turbo and the tank has a hose connected to it that goes to the scavenge pump which sucks the oil out of the tank. The scavenge pump is located on the rear of the motor on the drivers side. The pump is a simple gear style.

http://forums.pelicanparts.com/uploa...1305146962.jpg

http://forums.pelicanparts.com/uploa...1305147183.jpg

http://forums.pelicanparts.com/uploa...1305147266.jpg


If you run the engine and have the oil scavenge line disconnected from the drip tank, don't forget a nice plastic pan underneath, the flow through the turbo should look like this. That should give you an idea if your getting good flow, bad flow , or overflow.




http://forums.pelicanparts.com/uploa...1305147426.jpg


While the engine is still running put your thumb over the scavenge pump return line to see if you can feel good suction. If you have suction you can stick the line in your pan of dripping oil and see if the pump adequatly evacuates the oil. I would also disconnect the line from the scavenge pump and run something like a coat hanger through it to clear it and the rinse thoroughly with a spray can of engine degreaser.

Let us know what you find.

Cole

Gents.

A great day before I headed off to work. I took the airfilter off, loosened the airbox and did a check for oil. Residual oil found in the airbox at the oil tank breather hose connection and also residual at the airbox and tube leaving the airbox on the left side. Not much but some.

For me, there is no such thing as excess information. It in fact it is greately appreciated.
I dismounted the switch assembly to look for the ball.
I must say that todays little session was to me, very rewarding. Peace and tranquility rested over my Porsche and garage. I did not rush and truly enjoyed my given wrenching lesson.
The area around the switch was nice and clean, the line and assembly was "new" wih the blue banjo and braided steel line. Seals and swith seemed fine, the spring and 9 mm ball was in place.
One thing, the 12 nuts on the intake manifold was quite loose, I tightened those.

I did not have time today to do the work described in that great write up and well described procedure for the flow test. I will do that tomorrow.
You see, I had to go running around around the block a few times before work. My wife looked at me before we hit the sack last night and had to comment on my lack of excersize the past month.

I am looking forward to my second wrencing lesson tomorrow. As I read all of Your comments, it suddenly dawned on me how the forced induction works. In lieu of that, I appologize for my not well thought through comment on where and why the oil could pass through the IC.

G

What spring?

"what spring?"

Very good point.
Inside item #2,(see Cole's writeup) I have a spring wich is approximately 1" long. I will post a picture once I get home.
According to the mentioned writeup, there is no spring in item #2.
Which is correct, spring or no spring?

G

This may have been mentioned before, but if you have excess oil in the air breather assembly it could be that your oil level has been overfilled and spilled over into the intake system. You can check this by pulling the line from the oil tank breather and see if oil pours out of that as well.

For what it's worth, I had similar symptoms as you and a rebuild of my K27 7006 cure the smoking issue at startup. I had about the same amount of oil in my IC. Mineral spirit cleaned it good.
Did you remove the muffler to see if the turbo has excessive play? Mine had a fair amount of play and when I took it apart, I saw that the compressor wheel had been rubbing on the inducer.
I totally agree with not rushing into spending money for a new turbo until you know that this is your problem.
According to Porsche manual, your radial play should not be more than 0.35mm measured with dial gauge and your axial play should not exceed 0.65mm measured with feeler gauges at the turbine tips (between tip and housing)
David

Overfill...I'm not sure. I thought that I would have seen more oil in the airbox. I'm going down to my garage as soon as I'm done writing this for a double check.

Enclosed is a picture of the assembly, including the spring.
Is that spring supposed to be there?

I'm hoping that my oil issue can be related to a turbo seal and that a rebuild would do the trick.



http://forums.pelicanparts.com/uploa...1305226775.jpg

I don't think there should be a spring. If so, it sure would be listed in the diagram

I also thought it was strange that it was not depicted in the diagram, after sjf911 pointed it out for me.

I'm back from the garage. The air box, the hose from the oil filler neck to the air box and the tube from the left side plenum, are all coated in a thin film of residual oil. The oil seems to have been there for quite some time as it is quite dried out.

If it was a overfill at some point, wouldn't the oil in the IC have disappeared by now?

My option here seems to be to clean out the IC and hoses, check the flow and just drive to see if
A) it smokes.
B) it smokes and the IC fills up once again.
C) no smoke. A possible overfill at some point.

I had the exhaust off last year and checed for play in the turbo wheel. It seemed to be alright at that time. It was a smoker at that point also.

If A or B is correct, I assume the turbo rebuild is due...or maybe a 7200 hf is in order.

G

Hoyo.

The 9mm ball is simply an oil feed restrictor, The spring is optional and mainly used with a Garrett Turbo application to provide added restriction pressure and can be use with the KKK if you feel you need more restriction.

Cole