oil cooler cleaning

[Chased1]

Hello i boaters, i ve got a 1999 mercruiser 7.4 with a clogged engine oil cooler. The problem is its clogged with small stones and they re jammed in there pretty tight, tight enough that i cant just blow them out with air. I might have to use a long punch to get them out but im not sure if there is any oil passing through the honey combing inside. I dont want to damage the water passages with my punch. Has anyone seen how the passages are made ? Are they drilled in a solid block of copper ?

 

[Bt Doctur]

A thin brass rod is your best bet but I`d be more worried about the smaller stones that passed thru. Most coolers made by soldering/brazing the tubes inplace.with rings and end section, placed inside the shell and soldered or brazed then end caps soldered in place
Should you be going where you really done belong with a water cooled engine a sea strainer is highly recommended

 

[Scott Danforth]

Depending on the size of the tubes if they are quarter inch or 5/16 of an inch, the wall thickness is only about 20,000 stick for the tubes.

use a wooden bamboo or other BBQ skewer, the ones you use for grilling shrimp or kabobs. You want something that is extremely soft to try to work the stones out.

most likely you have quarter inch tubes, and the ID of that is about .2"

it cost more to repair that cooler than it does to buy a new one if you damage it. New one is less than $100

 

[Chased1]

Yea those rocks arent comming out with gentle tapping with a peice of bamboo. Not sure how the got wedged in there so tight. I bought the boat like that btw. I dont beach it