Overheating + brown foam in coolant tank

[ali_mac]

Afternoon all, long term stalker but first post so here's my problem, I'm hoping someone could maybe share a similar experience, and maybe shed some light on what the issue is...

After putting our 1986 1.9 DG through its paces earlier this year to make the ferry back to the UK, began overheating every now and again, the temperature gauge wouldl often swing from centre to high and sometimes sit in the middle, a few days after returning home the oil pressure light light came on along with the buzzer (just about giving me a heart attack)

Upon checking the coolant tank,the level was low and full of a brownish foam. I did a compression test, and 1&2 were low, with 3&4 appearing normal. I checked underneath the low compression-suffering head and there is evidence of a coolant leak from the water jacket seal. A plastic flange that joins a coolant line from the tank to the head also appears to have partially melted under heat, causing even more coolant to leak.

My question to you all is: are these symptoms all linked to a common underlying cause? Thanks for reading, your input would be much appreciated.

[SamsBus2012]

Blown Head Gasket on 1&2???

[kevtherev]

Difficult to call
It's not usual to get oil in the coolant on a DG, mostly the other way round if the barrel seals have been compromised.
How often was the coolant changed?
once every two years is recommended.


The low compression is worrying, that is a can of worms waiting, and could be caused by a quite a few things.

[ghost123uk]

Oil in water, leaks from head to case seal(s), low compression, oil buzzer. I'm afraid that adds up as a new or used engine is needed, or, if you are up to it, a rebuild (IF you have the knowledge, experience, place, tools and money etc). I went down that same road about 8 years ago. I ended up (after some failed attempts with "this and that"), getting a very good used motor off billy739 on here. It's still going strong

[ali_mac]

Unsure about the last coolant change, previous owner got it serviced at an old school type mechanic who knew his way around these engines (apparently), so hopefully correct change intervals/type was used. Having said that, I've been suspecting that he has not, and the studs have corroded and the head shifted compromising the seals etc. Is that a possibility?

The fact oil is finding its way into the water somewhere does not fill me with too much confidence

I've never re-built an engine, but I can wield a spanner, and know people who can help, so keen to give it a go. I'll be dropping and stripping the engine over Christmas, thanks for your comments.

[what2do]

Head studs don't corrode terminally because of one coolant change being of the wrong type, several years of the incorrect protection causes this, thus, your predicament can't be laid at that door.

A good second hand engine which can be heard running will in my opinion be your best bet unless you're capable of removing broken studs yourself. They're a 'joy' to do and very satisfying at times but can be time consuming.

[ghost123uk]

A good second hand engine which can be heard running will in my opinion be your best bet

+1 on that.

[DoubleOSeven]

I'd remove the engine, pull the heads off and replace the head gaskets (water leak) and the piston rings (possible low compression). I say this because once you've done this you'll know what to look for should; you need to look for another engine or by that stage be confident/experienced enough to rebuild your own. This is the cheapest and most rewarding option, in my opinion.

[what2do]

I'd remove the engine, pull the heads off and replace the head gaskets (water leak) and the piston rings (possible low compression). I say this because once you've done this you'll know what to look for should; you need to look for another engine or by that stage be confident/experienced enough to rebuild your own. This is the cheapest and most rewarding option, in my opinion.

Kind of depends on the op's experience, even a direct transplant is going to be considered rewarding to a novice.

[ghost123uk]

^^^ Tis true, removing main studs, pistons, liners, replacing worn parts, finding a cracked head, etc, liner "O" rings, special sealants etc etc, then re-assembling and hoping (after spending quite a lot of dosh) that it's all going to work correctly is a bit daunting unless you have done it a few times before

[CovKid]

If I was faced with it, the only way for me would be to rebuild another lump then transplant. Marginally less stress. Mines coming up for renewal I think and not decided what to put in there. Much as I adore v-dubs, the T25 engine is neither powerful or economical and the waterjacket business is irritating. Don't want diesel either. The scooby is a well designed lump - if only it was in my budget. Perhaps I should start collecting bits. My lad wants it after me so have to think ahead a bit.

[Smosh]

Noticed a similar problem on my van today. Coolant had completely disappeared after being left sitting. Leaving behind a milky brown sludge... Balls.

[New Kentish Campers]

Unsure about the last coolant change, previous owner got it serviced at an old school type mechanic who knew his way around these engines (apparently), so hopefully correct change intervals/type was used. Having said that, I've been suspecting that he has not, and the studs have corroded and the head shifted compromising the seals etc. Is that a possibility?

The fact oil is finding its way into the water somewhere does not fill me with too much confidence

I've never re-built an engine, but I can wield a spanner, and know people who can help, so keen to give it a go. I'll be dropping and stripping the engine over Christmas, thanks for your comments.

Not a bad idea to flush the small coolant pipes which run around the engine bay as I think they serve the heads and if they become blocked, will help give cooling issues. I took mine off last year and was amazed at the amount of crud that was in them.

[ghost123uk]

^^^ VERY good point. That's what did for my engine (around 8 years ago now) and could easily have wrecked the replacement

This is what you can find (here is that picture again )

[CovKid]

Damn it - that picture again. Like cat poop. I reckon Rascal did that when your head was turned.