Replacing the Head Gasket - Any pointers?

[benough]

As the diagnosis continues, a top up of the oil revealed the "milky white paste of death"

Quite certain the head gasket needs replacing. It would explain why I am slowing losing coolant even though a pressure test showed no leaks.

Also it has been burning oil and heating up since my brother had it from thursday which also adds to the head gasket being the culprit

So can anyone offer any advice when replacing it?

Gonna be going off the Bentley Manual.

[Preen59]

Take it to a good mechanic, let them do it.

Its not an easy job, and you need the gear and know how to do it.

[RedMk2Gti]

This is the BEST and CHEAPEST alternative if you don't want to pull the head off.

http://www.rxauto.com/

I have used it in my ex-Mk2 with great success. There are similar products in Repco and Superchip auto in $10 a bottle but I didn't trust them.

More story => http://forums.vwvortex.com/zerothread?id=2464602

[Peter Jones]

In my experience the head gasket is usually just the victim of some other root cause.

Be prepared that there may need to be some headwork done. Head gaskets are pretty tough things and don't usually spontaneously fail due to old age. Corrosion can be an issue though if the right coolants aren't being used.

Make sure you get the head checked out by an expert and preferably pressure tested.

Hopefully the new gasket will sort it out. Remember that you'll need new head bolts too, they're stretch bolts and can only be used once.

Pete

[RedMk2Gti]

In my experience the head gasket is usually just the victim of some other root cause.

Be prepared that there may need to be some headwork done. Head gaskets are pretty tough things and don't usually spontaneously fail due to old age. Corrosion can be an issue though if the right coolants aren't being used.

Make sure you get the head checked out by an expert and preferably pressure tested.

Hopefully the new gasket will sort it out. Remember that you'll need new head bolts too, they're stretch bolts and can only be used once.

Pete

That's correct, in my case. The HG was gone due to radiator burst and I kept driving for 5 minutes with coolant The sealant solution worked perfectly for me.

[benough]

I have replaced the radiator and a hose b/c the tank had a huge crack in it.

So before that it was driven short distances and topped up. Not the best.

I think it was changed a bit late in the game

Yeah Pete I am getting the head shaved. Also I have got all the new bolts and gasket(s) as well.

First of all I am gonna get it off and have a look see. The original radiator lasted a long time so I think the coolant was good and have been using good stuff ever since. Hoping corrosion won't be an issue.

It hasn't been blowing smoke, even since the gasket had gone so I am guessing we won't need to do the valves.

[Jmac]

Cylinder leakage test will show this fault for sure mate if done right and if found like Peter says there wil most likely be pits in the head, hopefully not too deep and can be shaved
JMac

[Valver.]

It's perfectly 'DIY-able'. Just have the head shaved - might aswell get them to replace valve stem seals and even guides whilst it's off, then flat the block surface with a large sanding block and some wet 'n' dry or even scotch brite pads on a 90deg angled die grinder (better for a cast iron block than than the sand paper, which is better for alloy in my opinion).

Just make sure it's all clean and flat and you cannot possibly go wrong

Also clean all the head bolt threads in the block with compressed air and a clean tap otherwise any engine oil left in them may be forced up and affect the sealing of the gasket. ARP head studs and nuts make the head easier to fit back up as well.

Oh, and use a good torque wrench when you tighten it back down (after having removed the head bolts in the correct order of course).

[benough]

Well I took the plunge and got the head off aaaand it's not looking good...

Is the head ruined? The holes where the coolant runs through are all rusted and they all look much bigger than than the holes on my new gasket do.

Same with the block.

So what do people think my options are?

Cheers

[Golf Loon]

Block may clean up. Head is gonna need some welding and resurfacing, or replacing with another.

Take the headgasket off, clean out the bores and put a bolt back in each bolt hole to clean them out and then clean up the surface of the block.

Show us a pic of that and we`ll give you a verdict.

I can help with a cheap replacement head or a full motor at budget prices. Let me know if you need the hook up.

[h100vw]

All looks pretty normal to me chief.

I have done plenty of dub head gaskets in my time and yours isn't the worst I have seen. The water ways in the gasket are smaller than those in the block. I reckon they are set to control the water flow.

Your head and block look like they have been run with plain tap water in the past.

Clean it all up the best you can and put it back together after the skim.

EDIT
Do you think it's that bad Matt?

Gavin

[Golf Loon]

Hard to tell from those pics.

Clean up the head and the waterchanels and then lay the new head gasket against it. If its not massively different it will be ok.

I agree with Gavin, thats what tapwater does to engines.

[gtimk5]

The electrolysis in the head is very bad. I reckon it would be cheaper to grab another one off Loon.
The blocks are usually ok. Good luck with it,
Andrew

[h100vw]

Funny thing, all the ones I did went loads better due to the increase in compression ratio!!

Except my G60 where some German mechanic had fitted a std gasket instead of the proper metal one. That slowed the car down a fair bit, due to the drop in compression.

Which makes me think that if the skim needs to be pretty severe to remove the corrosion. A metal gasket might be the thing to restore the CR to normal?

Gavin

[Golf Loon]

The first or second skim is usually alright and just increases compression slightly.

You need to get someone to do it, all valves must be renewed, change the valve stem seals at the same time and get the head pressure tested and skimmed. It should come back ready to bolt back on.

You will pay $500 or so for the head to be serviced.

I think I have a South African engine there with a big valve head on it, could be the time for an upgrade
I`m actually closed until the 5th, but if I go in for anything, I will see what I have.

It will be hard to get someone to do up that head over the holiday period.