1939 Dodge Flathead Six - oil in the coolant problem

[JD&COKE]

Hello everyone.... 

I have a 1939 Dodge wc pickup with a flathead six engine.

I have recently noticed that I have engine oil in the coolant, the truck starts and runs beautifully, but up to now, no one seems to know why this is happening.

I am concerned because all of my water hoses are oozing oil, and I have half an inch of engine oil floating around in my radiator. There is no water in the sump.

I am hoping someone can give me some advice so I can fix this problem....

i do not have a specialist here in the UK that can give me an answer...

thankyou in advance for any advice you can give.

[JPP]

JD&COKE,  I am sure you'll get lots of ideas but seems like could be a block crack.  The oil runs 40psi and the water coolant is low pressure,so the driving force is from the oil to the water.  A test would be to pressurize the water side at high pressure and see if you get water in your oil.  This will confirm that you have a crack somewhere.  Just my 2 cents.

[Reg Evans]

I would flush the cooling system and refill to see if this happens again.  Maybe, if you are lucky, someone in the past poured oil in the radiator as a sick joke.

Your 1939 radiator is a non pressurized one.  If you were  able to pressurize it to 40lbs you would be looking for a new radiator too.

[NiftyFifty]

If you have owned this a long time, I’m also thinking cracked block unfortunately...not realky many other methods to have only oil in coolant...if it was mixed I could maybe say head gasket...but even then that usually means coolant in oil, not other way.

[JD&COKE]

Thanx for the info... I’ve only had the truck 12 months and it’s hardly been used, so think I’ll flush out cooling system first, refill it and hope for the best.... 

 

[Don Coatney]

Has the oil level on your dipstick gone down? Is your radiator filled all the way to the top? Have there been any plumbing changes on your oil filter lines? When you say the water lines are ozzing oil are the clamps not tight?

[JD&COKE]

15 minutes ago, Don Coatney said:

Has the oil level on your dipstick gone down? Is your radiator filled all the way to the top? Have there been any plumbing changes on your oil filter lines? When you say the water lines are ozzing oil are the clamps not tight?

Hi there Don... dipstick level has not gone down, radiator is not full to the top, there is no oil filter, the oil is ozzing from the full length of rubber pipes and the clamps, and yes they are tight. Oil is also ozzing out from the heater pipes....

Edited February 28, 2018 by JD&COKE

[Don Coatney]

Have you ever replaced the rubber hoses? What kind of anti freeze are you using? Does the stuff in your radiator smell like oil or gasoline? Have you done a compression check?

 

[JD&COKE]

41 minutes ago, Don Coatney said:

Have you ever replaced the rubber hoses? What kind of anti freeze are you using? Does the stuff in your radiator smell like oil or gasoline? Have you done a compression check?

 

Rubber hoses have not been replaced but they look good and not perished, the anti freeze was already in the vehicle when I bought it, so I’m not sure what it is, the stuff in the radiator is oil. No compression check done yet.... 

have u heard of this happening before?

[NiftyFifty]

You may consider straight water after a good flush of the system, just as a test..no point ruining a bunch of new coolant.  I would run it a few times getting it up to temp and then drain the water again and see what you've got.

[Los_Control]

agree with straight water, but you might try vinegar instead.

 

it is a good cleaner, will knock loose the rust and scale in the old water passages, gentle enough to not damage the radiator or heater ..... and gives it a fresh clean smell 

 

I think maybe others might have a different suggestion for product to use, I would want something that would remove the old oil in the water passages.

 

Couple thoughts here, I use to use a radiator sealer. This stuff looked like brown molasses with little round rabbit poop in it. .... Think it was called bars leak dont remember. That product sealed 7 holes in a radiator that had contact with a fan. Is it possible you have something like this in your coolant?

Also what pressure cap do you have on the radiator? Possible you have to much pressure in the system and forcing it out of strange places.

[NiftyFifty]

Ya good point, I had a bad bad leak this summer and used a pile of sealer to limp the truck home...when I drained the coolant to swap my radiator a week back it almost looked like oil in it...but if he's got an oily substance actually seeping through the rubber hoses, I'm guessing it's not a coolant/rubber friendly substance.

[Jeff Balazs]

34 minutes ago, Los_Control said:

agree with straight water, but you might try vinegar instead.

 

it is a good cleaner, will knock loose the rust and scale in the old water passages, gentle enough to not damage the radiator or heater ..... and gives it a fresh clean smell 

 

I think maybe others might have a different suggestion for product to use, I would want something that would remove the old oil in the water passages.

 

Couple thoughts here, I use to use a radiator sealer. This stuff looked like brown molasses with little round rabbit poop in it. .... Think it was called bars leak dont remember. That product sealed 7 holes in a radiator that had contact with a fan. Is it possible you have something like this in your coolant?

Also what pressure cap do you have on the radiator? Possible you have to much pressure in the system and forcing it out of strange places.

Stands to reason. Sump level would be falling if you had a cracked block type oil leak. And you haven't mentioned low oil pressure.

[dpollo]

A very thorough flush and refill will tell the tale.  Here is a possibility.  At some time in the recent past (but before you got the truck) someone had the cylinder head off for an extended period of time and poured oil into the cylinders and valve area to prevent rust. Perhaps a lot of oil got into the water jackets at this time and you are now seeing the results.

 

In what has  (quickly )  become 60 years of messing with these engines, a lot of these engines, I have seen just about every ailment but never the one you describe.  I did run into it on a 250 inch Chevrolet and it was a crack in the block.  Given the difference in pressures, mentioned earlier, the loss of oil would very quickly present itself.

[48Dodger]

You are in the UK......so I'm not sure what the norm was in the 30,40's era.

How long have you had the truck in your possession, i.e. have you rebuilt the engine or have you had work done to it you can vouch for? 

Has kerosene or any other oil or oil base product been used in the past for engines in your region. Tractors in the U.S. have been known to use

oil as a coolant. If the previous owner was "clever" he may have used oil to cool the engine as he did his tractor. Oil doesn't have the cooling

properties like water, but are easier on an old engine or freezing conditions. I only say all this because I don't know how long you have had the

truck, what the practices are in your neighborhood and most have given traditional advice already...... 

 

48D        

[JD&COKE]

Thanx everyone for all your advice, I will be doing a very thorough flush as soon as the better weather comes.... I will keep you posted on how this goes...