Help Needed Oil cooler leak and oil in radiator

Eric in IL

SDD Junior Member
Joined
May 21, 2010
Messages
6
Reaction score
0
Location
Viola, IL
I noticed my oil pressure was a bit low a few days ago and heard and irregular rattle in the engine of my 1989 7.3 liter IDI diesel with 5-speed manual. Checked oil was really low. Probably should have been checking it more regularly. Added several quarts. Before starting the truck I checked the radiator fluid and found black engine oil. Decided to limp the truck home 8 miles. Rattle stopped almost immediately. Stopped along the way at a salvage yard and got a replacement radiator for $100 thinking an internal oil cooler may be the problem.

I called a diesel mechanic friend and asked what he thought could be the problem upon observing that my radiator had no internal oil cooler. He thought the oil cooler (on the block) could be the problem or there could be a cracked head. Hopeing for the former, I located the oil cooler which had layers of greasy oil with a shiny wet top coat (obviously leaking for a while), radiating in every direction.

I drained the oil (no coolant, not milky) and coolant. I just got the oil cooler off (after having to disconnect the exhaust manifold) and plan to replace gaskets/o-rings and check for holes.

My questions, finally:
Should this stop the oil from entering the coolant system?

What should I do with the radiator: 1.) replace it; 2.) clean it (how); 3.) just use the replacement or; 4.) take it for a rebuild at a radiator shop because it is 22-old and I do not want to fix it again?

Parameters: I am trying to fix this for under $500 and 16 hours of my labor (already spend 6 hours and $100).
 

Dogman

Full Access Member
Joined
Nov 19, 2007
Messages
1,789
Reaction score
2
Location
tampa,FL
Get the radiator cleaned and tested and put it in. Clean and Test the oil cooler to for any other leaks too.
 

dpantazis

#12
Joined
Nov 8, 2005
Messages
1,852
Reaction score
0
Location
under the cheddar curtain
jump over to our parent site, oilburners.net
there is more 6.9 and 7.3 idi stuff and folks there.

the oil cooler and orings are well known culprits.
get it apart and cleaned well. you should be able to fix it.
 

Eric in IL

SDD Junior Member
Joined
May 21, 2010
Messages
6
Reaction score
0
Location
Viola, IL
Problem solved

Oil cooler was in bad shape. Taking it off was a pain in the ass. Had to disconnect the exhaust manifold to take it out. Obtained gaskets for something like $6.00 and two large rubber o-rings from the ford dealer for the oil cooler. Washed out the cooler well. Wire wheeled the tube and painted to slow future rust. Used a hydraulic jack and vasaline to get new gaskets to slide into place. I have been driving for a over a month with no oil in the radiator. FYI the old radiator was in really bad shape. Mineral deposits were holding it together. Found a replacement at the salvage yard for $100. Totoal cost about $140, 16 hours, and two shirts covered in oil.
 

snicklas

Super Moderator
Staff member
Joined
Aug 10, 2008
Messages
424
Reaction score
25
Location
Greenfield, Indiana
Eric,

I agree with dpantazis, our sister site Oilburners.net has much more information for the 6.9 and 7.3 IDI's. A great deal of information and very helpful folks over there.

Agreed it is a pain to do.... and not easy to get in and out.

One thing I see, and I would verify this next door, but the oil cooler should have FOUR O-Rings, not two. I don't want to see you have to repeat the work, I don't want you to still have a leak. When you get next door, do a search on Oil Cooler and you will find a great deal of info on them. Several have been rebuilt recently.
 

Members online

No members online now.

Forum statistics

Threads
30,512
Messages
266,061
Members
14,625
Latest member
woodrow58
Top