Oil in Coolant .... question of the Day :-)

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Oct 22, 2007 | 05:33 AM

5000CDQturbo

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From: Ottawa, Canada

Oil in Coolant .... question of the Day :-)

if you were getting oil in you cooling system where do you think it would come from ?

>> there is no coolant in Oil ( pan ) . The possible area would be where the two fluids pass in the same area of the engine . The oil is at a higher pressure as the oil is getting into the coolant and not the other way round.

The two areas that I think the problem could come from .

1) The Turbo has a crack in it that allows the oil to flow into coolant . ( this is located at the bearing area of the Turbo )

2) Head gasket failure ... oil being forced into the coolant at the head .

what do you think ? :-) Superdave

1987 5000CD qt

Oct 22, 2007 | 05:55 AM

serf2k

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My vote: head gasket

Pull the plugs and check colour - is the back one (#5) is probably an orangey to whitish colour compared to the rest of them? Reinstall and run the engine up to temp. Remove plugs (caution - hot! plugs, brittle coolant fittings, electric fan , etc, etc.) and hold an inspection mirror over plug holes. Fog on the mirror is a coolant leak in that cylinder (probably #5).
On MC engines, there's a coolant passage close to the cylinder wall on #5 that tends to go - especially if the car has ever overheated (warping the head). The oil in nthe coolant tank is actually a combination of oil and combustion product, making the tank an ugly mess. Prolonged leakage will result in a drop in compression in the offending cylinder (due to increased blowby), and the failure of plastic and rubber coolant fittings/parts.
Cheers!

Oct 22, 2007 | 06:20 AM

5000CDQturbo

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From: Ottawa, Canada

thanks

thanks for the excellent feedback. The car really hasn't been over temped and there is no pressure build in res.

> I've seen no change in the exhaust, re white smoke .
> The contents of the res is definitely oil but the coolant is dark and cloudy with particles in it .
so this is combination of carbon and oil ? Blow by sounds like the problem .

I'm going to follow through with your test plan . ( I like the safety notes , always a good to have on the mind )

cheers
sD

Oct 22, 2007 | 09:40 AM

Katman

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If an automatic..

If an automatic.. (But not your case, I think) you can get coolant and AFT swapping places at the trans cooler.

How do I know..? :-)

Trans was empty (hence, no drive), and coolant resevoir had all the ATF in it!

Oct 22, 2007 | 10:20 AM

serf2k

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As Fire Marshal Bill sez....Safety First, kids!

The plastic warning is an important one for anybody working under the hood with a hot engine - the plastic overflow spigot on the rad can become super brittle and scorch you pretty good if it breaks off when leaned on.
Cheers!

Oct 22, 2007 | 10:36 AM

5000CDQturbo

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From: Ottawa, Canada

Re: As Fire Marshal Bill sez....Safety First, kids!

I have a nasty story of a rad hose exploding on my 74 corvette . I got it from the waist down .
I burned Big Jim and the twins and of all things both ankles ( because I was wearing socks ) Demeral is a good thing . Or the time I adjust a battery I was charging and it exploded . Thank fully it was under a bench when it happened ... the twins were not injured .