GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: dan_thevdub_man on 16 March 2014, 19:12
-
Right guys. Here's the biggy. Took car for service today went in fine came out with a dodgy coolant temp light flashing. Got home to nice the dreaded gunk in the expansion tank and oil cap . So iv decided to do the headgasket myself with a mate. We both pretty handy so why not. Read up that I'll need change all the seals and gaskets and the head bolts and whilst I'm at it though id do the radiator and expansion tank just to make sure all the junk is cleaned out clean all pipes and breathers. Going do the water pump aswell. Is there anything else. Any help is welcomed but please don't tell me not to bother or to just scrap the car as that is not an option. For the record it's a mk3 2.0 8v anni agg 106k miles
-
Head gasket change I would also change valve stem seals since you need to take head off anyway. Not much more work but a lot easier with head off.
I would do:
new head gasket incl. new bolts (old plastically deform when tightened up to correct torque)
stem seals
rocker cover gasket
cam belt (+ fan belts if they have done some mileage already)
water pump (you could clean it thou)
thermostat
obviously new oil and coolant
however I would first check the oil/water heat exchanger.... if that fails you get same symptoms... curing that is a 2 hour job (including flushing cooling system)... rather than whole weekend for the above...
-
Where is this exchange/oil cooler that you mention? Iv never heard of it
-
Where is this exchange/oil cooler that you mention? Iv never heard of it
I believe that's the oil cooler (part 18 on this diagram)
(http://www.partscats.info/volkswagen/en/Img/vw/121/121115500.png)
I know the seals can fail on this but that normally gives you a drip, and they are not connected to the water in any way. itavaltalainen your needed to explain a bit more :smiley:
-
Right pig of a job on a 16v with aircon! No access! :angry:
But on an 8v it should be easy!
Agree with BB in that I dont see how the oil and water would get together in the oil cooler.
-
It's not a bad job on the 8v with air con (Unless you sell the seal to a customer before you get chance to fit it :grin:)
Mine dripped oil from the seal so i didn't need to remove the whole oil filter housing to change
-
ive heard of a few hailing here, the actual water jacket gets a hold in and allows oil to seem in and visa versa, as said it may not cure the issue but by far its the cheapest and easiest way to go through first.
-
they can corrode over time and since you have water and oil in there it can actually mix. doesn't happen very often but before I go to headgasket would check that...
you can take it off... connect one of the water ports to garden hose... flush it vigorously with water, then block the second one with a bit of garden hose (blocked with a cork). now fully open the tap and see if there is oil/water coming out on either side of where it screws to block and oil filter.
-
Agree with BB in that I dont see how the oil and water would get together in the oil cooler.
:huh: :shocked: all your vast VW experience and you are not aware that it is an oil / water exchanger.
I have seen many fail, over time they corrode and will lead to oil and water mixing, easy enough to check, join the pipes together and then flush through, if it comes back then your looking at head gasket.
-
Many?
How come you have never mentioned it then Wayne?
-
Just trying to think what chemistry would be needed to cause the ally to corrode.
I mean the water jacket has fluid in it constantly. Sorry I mean coolant, which should not cause any corrosion. And I cant for the life of me see how oil can corrode ally!
-
I know these are a popular part (well they are made by most big brands for the after market) so I guess they do fail. I can only guess poor anti freeze make them corrode (the amount of people I tell and tell again to only use g12 spec red anti freeze in their mk3's is shocking!)
-
Thanks everyone for the replies. This is what I'm going to do. Replace expansion tank, flush the radiator and engine (what's best way to do this and for how long should I do it for. Also the oil oiler, how do I test this and what do I look for ? Also what's best way of flushing the rad, just disconnect top and bottom hoses and flush garden hose. Then when all this is done, top up with g12 and distilled water? Am I right?
Also, if my head gasket had gone surely there would be more cream in the oil cap (non at the mo) and some on the dipstick too?
-
Before you go mad and replace the head gasket find out when it was serviced did the coolant get topped up.
I have seen G11 Blue/green mixed with G12 red/pink and the results sound about the same as your experiencing.
Has your golf shown signs of over heating if not then the head gasket should be ok.
Some times the heat exchangers split but not at 106, miles you would have a lot of coolant mixed with the oil.
Do a compression check both hot and cold if you can borrow a coolant pressure tester do that aswell.
-
Just trying to think what chemistry would be needed to cause the ally to corrode.
I mean the water jacket has fluid in it constantly. Sorry I mean coolant, which should not cause any corrosion. And I cant for the life of me see how oil can corrode ally!
If your coolant is the wrong strength or old it can cause major damage to Aluminium very quickly.
Did you learn about Anodes and Cathodes all those years ago? Its all covered there.