New guy from KY needs help!! '90 Ford F-250 7.3 IDI

[kymead]

Hey all.... I am new to the site, and new to diesel trucks... I just bought a '90 f-250 auto w/ 7.3 IDI and I love it, but I had a bad discovery today.... pulled the dipstick because I was planning on doing an oil change this weekend and it was milky!!!!???? Now I was gasoline engine mechanic for 10years and automatically that tells me blown head gasket or possibly something worse/more expensive. The crazy thing is it doesn't smoke and the motor purrs, and no overheating. Usually in the past my experience w/ blown head gaskets the vehicle would get hot fast and eventually overheat in a hurry...plus you would have smoking or steam etc..from tailpipe.... are diesel motors better at discuising these symptoms???? I use this truck everyday for my business which consist of driving a route all day for 6 hrs more or less...and I can't miss a day since it is my new business and I am the only employee......is there anyway of testing it to see what the actual malfunction is? Also someone suggested to me since its running fine as of now to drain the oil, flush it, fill it and include some K&W stop leak and see what happens...A little bit of info from the guy I bought it from told me that it a oil leak around where the oil filter attaches to the motor, which he replaced the $200 part and fixed the leak...but he also told me that before he replaced it he hosed/degreased down the engine to clean it up and thinks that some of the hose water may have gotten in to the engine that way...??... what do you guys think any suggestions advice would be greatly appreciated... And I hope you all are having a great holiday weekend..Thanks again, new guy.

[SmokeyWren]

'90 IDI I don't know about. But the first place I'd look is the engine oil cooler. On my '99.5 the oil cooler is located on the side of the engine between the water pump and the oil filter. I suspect yours is there too, but post in the 7.3L IDI forum and ask the experts on that engine.

On mine, the base for the oil filter is also the base for the engine oil cooler. The base for the other end of the oil cooler is at the water pump. The water pump pushes lots of water through the cooler, to cool the oil in the oil passages in the cooler then dump the heated coolant back into the radiator. So it could be the oil cooler gasket, or it could be that the oil cooler has gone south with rust or cavitation or some such.

But coolant in the oil has to come from some where, and it doesn't sound like a head gasket, so I'll bet on the engine oil cooler.

But coolant in the oil can ruin the engine in a heartbeat. DO NOT run the engine until you get that puppy fixed with fresh oil in the crankcase. But you knew that.

[kymead]

Thanks buddy, see these are things I need to learn about diesels... I will check oil cooler and go from there. I also took your advice and posted my question in 7.3 IDI forum...I will keep you up to date...thanks again.