Avve

Hi, I just bought myself a Euro 16V 1986, 5 speed, 108000 miles. I didn't pay a lot since the seller had noticed oil in the coolant. However, it doesn't overheat and there is not much white smoke from the exhaust. Neither does it use more than just a little coolant. The oil is still fresh, no gunk or water. The engine was replaced a couple of years ago after overheating on the german Autobahn, due to a defect hose, so there's no history about the "new" engine. The radiator was not replaced at the time.
My plan: I will pressure check the radiator(s), and also check the comb chamber compression incl check the plugs. Hopefully it is "only" the radiator that's broke...
Question: Any ideas what more to look for (hopefully without having to unnecessary pull the engine)?
Avve/Sweden

marton

could be a faulty oil cooler which sits in the radiator.
Do a search for this problem in this forum

Marton

Mrmerlin

need more info about the oil , is there coolant in it , is it milky, have you tried disconnecting the oil cooler lines from the radiator and just connecting them together, use a good hose and set of clamps so the oil lines stay together with engine running.
Are you seeing bubbles from the coolant tank with the cap off? Has this engine ever overheated or had a new set of headgaskets installed?

Steve Cattaneo

I would also do a compression leak down test, which is the best method to check for a blow head gasket or cracked head. Engine oil mix with coolant will look brown; Transmission fluid will look like strawberry milk.

Avve

Hi, no, this engine has probably not been overheated , unlike the previous one, but I do not know much about this car. It was originally sold in Italy, then imported back to Germany, and finally, Sweden. So no service history except a receipt from the german company who replaced the engine back in 2002.
I will additionally try to perform a compression leak down test and also check for bubbles in the coolant tank. The oil still looks like new, clear and shiny.
This will take some time, thanks for now
Avve

Mrmerlin

so is there oil/coolant mixing? do you have coolant leak ? What is wrong with your car?????
Sorry but I am confused with your post, try to be as specific as you can.
add as much info as you can, even seemingly unimportant things could lead to a better place to start looking for your problems..............Stan

Avve

Hi, sorry if my swedish-english is hard to understand: The oil within the engine is just fresh and fine, there is no mixing there. But there is oil in the coolant, fresh oil floating in the rad tank. The coolant level is still OK, but then I haven't driven the car the last month, i.e. since I bought the car. When I bought the car, we drove a couple of miles and it went just fine, no tendency to get hot at all. And just a tad of white smoke from the exhaust (the car had been sitting outdoors for several months, in the scandinavian winter).
I will perform a check-up according to the suggestions here on the forum.
Additionally I just noticed that the previous owner has overfilled the engine with oil, it reads about at least half an inch above the upper mark on the dip-stick. The engine starts after a slight hesitation but then the battery needs to be charged too. The engine also vibrates/stumbles/hesitates (hope you get what I mean here) around 2000 rpm, perhaps there is some kind of ignition problem just there, but not higher up in the rpm's.
I think I'll spend some hours in the garage figuring things out. Avve
and yes, this is my first 928, so I do need advice along the path
Question: Do I dare to drive the car at all at the moment?

Mrmerlin

I would first remove some oil from the pan so its not overfilled. You say there is oil in coolant tank , is it mixed or does it look like the oil in the engine?

Avve

Hi, the oil in the coolant tank looks just the same as in the engine.

Mrmerlin

if thats the case then you may just have a head gasket that has failed, or the oil coolant tank has sprung a leak or someone has poured oil into the coolant bottle , those are the things I am coming up with

Avve

Oh boy, now I have several options what to do
I'll start with the rad and check for leaks, pressurize the coolant system, and start from there. It would be pretty uncool to remove the heads just to see that the gaskets are OK...Anyway, the build continues and I am about to remove everything electric (except the elec windows) and measure for the roll cage.
Thanks for your input, I'll get back when finding the cause of the oil in the coolant problem.
Avve

Avve

Finally I have time to deal with my 928 (=vacation). Initially I had some oil in the water but no white smoke when starting the car. Now I have no coolant in the tank but lots of it in the pan... And still oil in the remaining water/coolant of course (and no, I didn't dare to start the car today). Will pressurize the radiator within the next week and if broken, I'll order an all-aluminum one.

Mitch Johnson

My 928 puts just enough oil in the coolant to discolor the reservoir, not enough for me to get too worked up about....probably head gasket, but is it serious enough at this juncture to go there?

docmirror

Remove your spark plugs, and look for one or two that are nearly clean. These will be the ones where there is coolant getting into the combustion chamber. You can also do a compression test, and the ones that are leaking should be somewhat lower pressure than the rest.

At least you should be able to tell which side must come off. It's best to do both sides, as the other side may fail in the near future. This happens to cars that sit idle a lot.

Avve

My car has hardly been used since 2002, when the car was brought back to Germany from Italy. An older swedish man (around 80) then bought the car with his son but the engine broke down on the way to Sweden, so a used engine from an auto' was put in. I have the receipt, and the engine change cost around 7500 USD. I am the third owner in Sweden. Still, not using the car didn't prevent the present engine problem...
Will check the spark plugs this evening.