A bit of oil in my M35A3 coolant

Trailfinder

Member
33
1
8
Location
Springfield,VA
Replacing the shutterstat on my M35A3 required draining the coolant. When I drained the coolant it appeared dirty. When I poured the coolant into 1 gallon jugs from the 5 gallon pail I drained the coolant into, I noticed residual oil on the bottom of the 5 gallon pail.

I searched the SS posts and found info on 5 ton and M35A2 oil coolers being responsible for oil in the coolant.

Is this a possibility on the M35A3? If so, does anyone know where to get a seal "rebuild" kit for the oil cooler of a M35A3?

Shutterstat problem solved. Fan clutch works now. Oil in coolant not good. :-(
 

rosco

Active member
Steel Soldiers Supporter
2,102
19
38
Location
Delta Junction, Alaska
While I don't have an A3, I have had that problem several times in commercial trucks. The oil cooler intself, springs a leak - its not a gasket problem. Replacing the oil cooler, solves the problem. Then before I refilled with antifreeze, I refilled with plain water, added a whole box of Cascade powdered soap (its low foaming), put a tarp over the radiator, and let the engine run @ 1500+ for an hour. Then flush a couple of times, and refill with antifreeze.
 

clinto

Moderator, wonderful human being & practicing Deuc
Staff member
Administrator
Super Moderator
Steel Soldiers Supporter
Supporting Vendor
12,545
731
113
Location
Athens, Ga.
I have an unusual case. Drained the coolant from an A3 with reasonably low hours and mileage (500 hours, 5K miles app.) and oil is in the coolant. So I assumed head gasket, oil cooler, etc.

Continued to drain fluids (this is a full service job) and the engine oil was exactly the right amount and no coolant contamination. Same thing for the trans. So the only thing that's contaminated is the coolant. I am thinking somebody accidentally poured some oil in the overflow tank, realized their error and didn't bother to flush it.

If there was a leak somewhere in the system (oil cooler, gaskets, etc.) there would have to be contamination somewhere else. I don't see oil being able to get into the coolant but the coolant not being able to get into the oil.
 

Heavy D.

Member
62
3
8
Location
Newport News, VA
I haven't posted in a while, and I had this same symptom on my own thread that I have not followed up on yet. I had it looked at by a pro, and he determined that it was not oil but fuel. Thinking about it they look a bit similar to someone not too familiar. Anyways the problem was the fuel injector cups were leaking... Apparently that is a common problem with the 3116. After trying to replace the cups failed, due to the copper washer being stuck in place and mutilated, the only option was to replace the head YUCK! Very very expensive. I hope this helps. Good luck!
 

ehinlein

Member
Steel Soldiers Supporter
57
12
8
Location
Pelham,MA
Trailfinder,

Hope you solved your contamination problem. My shutterstat is bad also. Do you remember the PN? Did you get it from Cat?

Thanks in advance.

Erich
 
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website like our supporting vendors. Their ads help keep Steel Soldiers going. Please consider disabling your ad blockers for the site. Thanks!

I've Disabled AdBlock
No Thanks