Oil film in coolant bottle.

amailloux · June 25, 2013

I pulled in an f550 2008 with leaking turbo drain. I popped

the radiator cap and there is a dark oily film on the bottle walls. The coolant does not have an oily film on it. I began draining the coolant, by the way it was full, and there doesn't

appear to be oil in my buckets. Then I looked in the bottom of the degas bottle and there are metal flakes. I do know the truck has had an egr cooler, and had coolant leaks in the past. I was wondering if front cover cavitation and perforation will allow just a small amount of oil in the coolant, and will it just stick to the bottle? At this point I am set on pulling the water pump for inspection, but what about the oil cooler. I will already have the turbos off, and I fear it will have shavings in it, or it may have a very small leak into the coolant. What do you think. Truck has just under 90k.

lmorris · June 25, 2013

If you haven't pulled it apart yet, test the oil cooler efficiency. If it's close to spec. then change it. There has been a discussion about trying to flush these to see if it will clean out the oil cooler instead of replacing them. If you do have it apart and there is quite a bit of cavitation, then I would change the cooler and have a look at the tstats while you got it apart too. Be creative with the story if this is Ford warranty. They get sticky when you dig in looking for the known concerns without valid reasoning.

amailloux · June 25, 2013

Do perforated front covers allow enough oil in to discolor the degas bottle? I have only had

1 other and the crankcase was filling with coolant fairly quickly, or is it more likely the

cooler leaking oil into coolant? It is a retail job for a very good customer. most likely going to replace oil cooler when turbos are off, and pull water pump and most likely replace front cover. Maybe over repairing, but I'll let the customer decide.

lmorris · June 26, 2013

Now that I think of it, I have seen this film in the degas before. Usually on trucks with poor maintenance and have been over heated. Perhaps this is your scenario. Oil can only get into coolant from the cooler though. I wonder if stop leak was put in the coolant too.

Jim Warman · June 26, 2013

+1 on the stop leak for any "sparkles" (not to mention many "exspurts" have their own idea of "fixing" coolant leaks).

A perforated front cover due to cavitation should put coolant in the pan. Scunge in the cooling system with no other symptoms could turn into a witch hunt. I'd suggest flushing and fresh coolant and, if the degas doesn't clean up, a new degas bottle.

For any possible overheating, make sure you look down inside the cooling stack. I've seen too many trucks with cooling stacks that look like they have a blanket stuffed in front of the rad.