In replacing the oil cooler and hoses on my 2005 XKR, I noticed an oil stain on the engine. It appears to be caused by oil seeping past one of the bolts (photo attached). Assuming this is the case, is this something I should worry about? Can I fix the problem by removing the bolt, applying Loc-Tite, and re-inserting it? Other suggestions?


Oil seeping past upper-right bolt.

 

It's the timing cover gasket, not the bolts. Yes, do take the opportunity to change both timing cover gaskets, the harmonic balancer seal, and valve cover gaskets (they have to come off anyways).

 

Ray, I’m curious as to what necessitated the changing of the oil cooler and hoses?

 

Having heard the horror stories about engines being destroyed when a hose failed, I always had my mechanic inspect them whenever the car was serviced. They recently told me that one was developing a small leak, so I decided to replace them all. I also found a good price on a replacement oil cooler & figured I may as well replace it, too. My car has only 100k miles, but is 21 years old.

 

The oil cooler hoses have a 10 year lifespan and should be changed religiously and periodically inspected for signs of leaks. If they burst you have less than 10 seconds before catastrophic engine failure.

However, the oil cooler itself? It’s not known to fail.

 

Thanks -- I think I'll just clean up the old oil cooler and have it powder coated in black.

 

Think twice.

the powder coating will trap heat and reduce the cooler efficiency.. bare or anodized aluminum will radiate the heat best.

Z

 

Thanks... just cleanup w/out powder coating.

 

That’s why there are special
Polymer coatings for calipers that let the heat out much better than the commercially available “caliper paint” and a special paint for radiators that is very thin, with much less build Up than regular spray paint, Eastwood sells a particularly good version of that.

If you are really wanting a coating of some type look into the Eastwood radiator paint. Amazon sells it : https://a.co/d/9ybC23F



Other than that option, just leaving it bare will let you take advantage of the cooler the best way.

Z