Oil in radiator?

[Dale Finch]

I just drained my radiator for its annual service, and the coolant, which periodically gets 50/50 mix added due to overflow, was nice bright green. However, as the final fluid was draining, it turned to oil. I scooped some out with a plastic bottle, so I could tell just how thick the layer was, and this is what I got, with 2 different lighting angles:

I did some research to get an idea of what the next steps are, and found these 2 older posts. Neither one really followed up on the problem, so my question is, should I just flush it with the washing soda per the manual, then refill and monitor, or should I dig deeper?

http://farmallcub.com/phpBB2/viewtopic.php?f=1&t=97730&p=769571&hilit=oily+coolant#p769571

http://farmallcub.com/phpBB2/viewtopic.php?f=1&t=52197&hilit=oily+coolant&start=15

Background: '55 Farmall Cub, tractor runs great, no water/antifreeze in engine oil (just changed oil/filter), no significant oil loss.

Suggestions? Thanks for any input.

[TallCoolOne58]

Yell ya what I'd do Dale, I'd fill the cooling system with tap water cuz it's cheap, run it for a bit and then drain it, see what you got. If there's engine oil in that, I'd def dig deeper.

[Skeebow]

I’m not sure how good it would do with the burp style system, but I watched a YouTube video the other day of a truck that blew a head gasket and dumped oil into the cooling system. After they fixed it they used dawn dish detergent and water and ran it up the road to operating temp then drained it (continued the process until no more oil was in cooling system) then filled it up with antifreeze mix. This may help to find out if it is continuing to leak into cooling system.

[Gary Dotson]

On a C-60 engine, there is no path for oil and coolant to mingle, short of a crack or porosity somewhere in the engine block. I believe I would do the washing soda flush and see what you have a year from now.

[Dale Finch]

I decided to (and did) order two boxes of Arm & Hammer Wash Soda, since I am under Stay at Home orders, thus couldn't go to Lowe's. As of now, I flushed the radiator a couple times with hot tap water, then refilled it and ran it until it was hot. Drained that, then refilled again. When the soda arrives, I will drain the radiator, fill with the soda solution, run it, drain it, refill with another batch of soda solution, and repeat. Then I will probably leave it with plain water for a bit (assuming no freezing predicted), and mow with it out at the farm. After a few heavy uses, I will drain it, check for oil, and if OK, will fill with antifreeze solution. If not OK...

Now on to finishing up my servicing checklist...over half way done!!

[Eugene]

I decided to (and did) order two boxes of Arm & Hammer Wash Soda, since I am under Stay at Home orders, thus couldn't go to Lowe's.

Grocery store, laundry detergent aisle.

[Slim140]

I decided to (and did) order two boxes of Arm & Hammer Wash Soda, since I am under Stay at Home orders, thus couldn't go to Lowe's.

You can go to Lowe's, hardware stores are open until further changes are made. Unless it's just a county closing thing.

[Dale Finch]

I was trying to minimize my outside contact, and with free shipping, decided I had a few other things to work on while I waited for the delivery! I actually tried to call Lowes and pay for it over the phone then drive by and pick it up, but after being hung up on once, then disconnected a 2nd time, gave up.

IMO, just wasn't worth my health for a few days' wait. now.... then later!

[Frozenstate]

To really clean it, first run it with Oxalic Acid, also known as wood bleach. The use the washing soda to neutralize it.

[TallCoolOne58]

For whatever it's worth Dale, I've given this some more thought. Although I've never had this particular engine apart, I do have a lot of experience with other engines. This engine ain't rocket science, an old flathead 4-banger, basically 4 B&S lawn mower engines in a row, except this one's liquid cooled using the simplest (and least expensive) method possible.

I have reviewed the service manual manual many times, looking at the engine diagrams. I'm wondering how close the drilled oil galleries come to the water jackets around the cylinders. A crack there could cause oil in the antifreeze, but not vice versa, with the engine running because the oil pressure would be higher than the pressure in the cooling system. Engine heat could cause this crack to expand enough to allow this to happen, and contract as the engine cools preventing coolant from flowing into the oil.

Just an additional thought if the problem persists, which for your sake I hope it doesn't. Hopefully its just a fluke and never happens again.

PS.Coolant drain flush and refill annually. Aren't you the ambitious one! I thought I was doing well with every other year. Of course I only put about 25 hours a year on mine so...

Best of luck to you. Hoping for the best.

[Dale Finch]

Yeah...if I'm REALLY lucky, I'll do the flushes, workout and drain and find no oil!! If that turns out to not be the case, I'll go from there. I'll let you know how it turns out...probably a few days. For now, I'm optimistic!

[k hutchins]

I had the same problem last year.
I drained the radiator, refilled with a regular cooling system flush, ran/drove it f[r about an hour so it was hot, then drained it again.
I then replaced the head gasket, since response on the forum was that a bad head gasket was about the only way coolant and oil could mix.
Like you l had no coolant in the oil, only a film of oil floating on top of the coolant.
After replacing the head gasket l have not seen any traces of oil in the coolant.
Food for thought, good luck.
Hutch

[Dale Finch]

Thanks. I plan to take that cub back out to the farm sometime this next week, and work it hard with plain water in the radiator. Then I'll drain it and see what's there. If it is reasonably clean and oil free, I'll put in 50/50 antifreeze. If not...

[Dale Finch]

I often forget to post follow ups, but yesterday I went out to the farm and drained the radiator. The tractor had been worked several 4-6 hour days mowing the pastures. I was almost afraid to look down into the tub! But I was SO happy to see almost clear water, with NO evident oil!! I am so relieved to not have a problem requiring any teardown.

That Arm & Hammer WASHING SODA seems to have done a great job!

[Donegal Cub]

Glad no major problem come up. Maybe there was old oil residue in the rad from a previous head gasket renewal