Fernando Esparza

I need advice to diagnosis the condition of my engine
1980 928 euro m28/10,
I got it running nice as far as start cold warm and idle.
The issue I have now is a lot of steam out of the tail pipe.
Compression test show 160 155 all except one piston with 130 psi. I am not an expert that's why I asking for advice but I have rebuild several engines successfully
Including a 2.7 horizontally opossed ( boxer engines).
I am not loosing coolant. But car is on jack stands and I run it an hour o two at the time
I have some milky looking stuff in the oil dip stick and also in the oil filling can.
And the coolant system pressure test show a very small leak at the top right corner of the radiator.
I will not give up with my restoration no matter how much it cost. I am almost ready to pull the engine and change the head gaskets.
Or change the radiator.or both.
Waiting for some expert advice thanks in advance

The Forgotten On

How long does the engine make steam? If it makes it for the entire hour you have it running you have a blown head gasket.

But even if it sin't blown, all of them are on the verge of blowing anyway so it wouldn't hurt to replace them

Having a little milky oil is normal from condensation if you don't drive the car all the time. Especially considering you have it on jack stands.

Also, the radiator leak could just be an end tank leaking. But if it is coming from the aluminum core you should probably replace the radiator.

Fernando Esparza

Steam for the entire hour if I accelarete for a couple minutes goes away and start steaming a few minutes later.not as much but it does
I was going to wait for a warmer temps. Since is only like 10 degrees up here. But you right if it not bed is probably just a matter of time.
Since the car was stored not running for like 5 years I just revived recently.
The radiator is leaking at the seam on the right side not at the core.
Hope I can fix it.
So you advice is fix the head gaskets. Cool thanks is pretty much what I was thinking.
Not loosing coolant probably because is still small leak

The Forgotten On

You were losing compression which either means bad rings, poorly seated spark plugs, or a bad head gasket.

The fact that you had a lot of steam makes it the head gasket. But it could just be the cold temps you are describing.

But yeah, it is only a matter of time on all of our cars as they are just paper gaskets.

Just hope that your heads are not badly corroded due to bad coolant or lack thereof. That has killed more heads than anything else on the 16V engines.

Good luck on your fix.

Pfc. Parts

Hard parts

Fernando Esparza

Where exactly you point the laser at, because I suspect cilinder number 4. The only one with lower compression ,is where the leak is at.
I don't understand why the car run so good, I repair lot of subaru head gaskets and they run bad, missing and shaking. But of course 4 and 6 cilinders. And this is a V8 . That could be why I guess,

Mrmerlin

to see if you have a coolant leak into the cylinder,
simply pull the spark plugs out,
any plug that is clean is being steam cleaned by coolant water mixture.
A plug that looks like it has brown tan or black deposits is OK .

Fernando Esparza

Also is really not a lot of water in the oil , I drain some oil and is clean. Yet anyway
Just some milky stuff in the dip stick and in the can where you put the oil.

Fernando Esparza

The plugs all look the same all have black deposit and none is clean , I did that and look specially at number 4 but like I say all have brown / black deposits can see no difference.

Mrmerlin

at this point I would suggest you drive the car for atleast 50 miles, check for leaks after 10 miles.
dont run it anymore till it can be driven

docmirror

Before taking things apart, you need to drive the car for a while. The crankcase venting on 'modern' cars is rather poor and a lot of the products of combustion are returned to the crankcase, or enter the intake to be burned out the tail pipe. What you may be seeing is the condensate in the engine being run through the intake and then the engine is shut off and more condensate collects.

This was a problem on several cars from the 80s and the only real solution is to drive them for a few hours at full temp and get the products of combustion out of the engine oil. It can't be done with a short run because the condensate will just go right back into the oil on each shut down.

Make sure your vent tubes are working right, and I would say leave the oil fill cap off when you start and run the engine. the oil temp needs to get up over 212 to boil out the vapor in the crankcase. A major part of the product of combustion is water vapor and it has to go somewhere, in a cold climate it will go out the exhaust as condensate for quite a while.

Pfc. Parts

Gargle

Mongo

Sounds to me like the low cylinder is where the head gasket leak is. Had the exact same issue on my old 944. It got to the point where it was pressurizing the cooling system and dumping half the reservoir on the freeway in a morning commute.

I have found there is one area of the headgasket where the water jacket next to the cylinder is the first spot where the failure occurs. Unforutnately, I don't have a picture to detail this, but it is usually at the rear of the cylinder head.

Wisconsin Joe

You say it's "10 degrees." Is that Farenheit or Celsius?

At 10F the car will never stop putting vapor out the exhaust.The combustion process produces water vapor and when the hot exhaust hits the cold outside air, the vapor condenses.

And if there's just a bit of "milky gunk" on the dipstick and in the fill, that's perfectly normal too. If you had a bad head gasket, your oil would be really bad. It would look like chocolate mousse. And you'd get the level going up a lot as the coolant filled the block.

Plugs all looking the same also tells me that the head gaskets are fine.

Mongo

Not all HG failures result in milkshake instantaneously. That is the worst case scenario of failure. As indicated above, failing HGs at the fire ring will cause pressurization of the cooling system.