Author Topic: Long term effects of ignoring oil in coolant? (Read 4671 times)

Fionn · « **on:** February 15, 2009, 09:50:35 am »

Hi guys, 89 Jetta 1.6NA, 204K miles on the clock. Engine is a donor I picked up cheap, I've put about 15K miles on it, estimate 130K miles total on the engine.
About 8k miles ago I started seeing oil in the coolant, for the last 4k miles or so this has been causing the coolant level sensor to flash the light in the dash. Today I cleaned a lot of the oil out of the coolant reservoir and cleaned the sensor, the flashing is gone now.
The coolant system isnt pressurised and I just did an oil change with no coolant visible in the oil.
Car will drive continuously at motorway speeds (about 75-80mph here) without heating, temps go up a bit above that but nothing outrageous.

There is no oil cooler as this is an NA, so I'm suspecting either a blown HG or cracked head. Just wondering if it's worth doing anything about it as it stands?

Fionn · « **Reply #1 on:** February 15, 2009, 12:00:23 pm »

Hi Andrew,
Thats a great post which I had not come across in my searches, I should have checked the FAQ of course.

Given that the amount of water in the oil at this stage appears to be minimal & the age / expected lifetime of the car, I think I will just keep driving it. It's rarely left for any period of time without being driven so hopefully this should keep the potential for rusting to a minimum.

I will need to clean the oil out every few k miles anyway to keep the level sensor clean so that will be a good reminder to keep an eye on things.

If I see any other kind of symptoms in the meantime I'll pull the head & investigate further.
Thanks again,
Fionn.

Powjetta · « **Reply #2 on:** February 20, 2009, 11:01:43 pm »

I drove mine with the same symptoms for thousands of miles with one eye on the temp gauge. One hot day it got hot and scared me so I replaced the head gasket. I could never see the leak on the gasket, and it took a while to get the radiator clean - I looked for special cleaner for cooling systems that was petroleum based. It's doing fine now.

madrogers · « **Reply #3 on:** February 25, 2009, 02:32:23 am »

It has been recomended to my company to use automatic dish washer soap to clean the oil out of an engine, it does not foam and works good , you may have to flush it thought a few times to get it all out .we use it on the hyw tractors what blow the oil coolers and you will get oil comeing out of the rad, it a big mess.
my 2 cents, Mark.

clbanman · « **Reply #4 on:** February 25, 2009, 06:21:05 am »

Cummins has told us to use washing soda for similar cases. (Fun cleaning out the coolant passages in an engine and the rad on a truck that someone filled the coolant system with hydraulic oil.) Drain as much coolant as you can, fill with water and add washing soda. Run up to operating temp (to allow thermostat to open). Drain, repeat until no sign of oil in coolant. Needless to say, this works best if you have the leak fixed first.

saurkraut · « **Reply #5 on:** February 25, 2009, 09:36:13 am »

I had a VW 16 valve gas motor that wasn't putting any combustion products in the coolant, but was passing oil from the high pressure oil supply passage to the head, into the coolant. I waited until spring to change it and the only issue was all the hoses and O-rings that came in contact with the coolant/oil mix got soft and slimey.

I installed a metal head gaskest and all new hozes and O-rings. Then I flushed it with ZEP industrial powdered soap, and everthing turned out OK.

Keep an eye on your hoses

Fionn · « **Reply #6 on:** February 26, 2009, 09:04:04 am »

Thanks for all the replies guys, they've given me some comfort at least.
She's been running away fine since (just a few hundred miles) anyway & I think I'll just continue to drive away & remove the oil from the coolant every few thousand miles or whenever it coats the level sensor badly enough for it to make the light flash in the dash.
Temps are all normal but I'll keep an eye on them too as always.