[Mk2] [Turbo] head gasket failure - Update, cracked block

[Turbolad]

I've stripped my block down to get the headgasket. I assume this would be the cause of my problems?

http://i706.photobucket.com/albums/ww62 ... G_0747.jpg
http://i706.photobucket.com/albums/ww62 ... G_0746.jpg
http://i706.photobucket.com/albums/ww62 ... G_0745.jpg
http://i706.photobucket.com/albums/ww62 ... G_0744.jpg
http://i706.photobucket.com/albums/ww62 ... G_0743.jpg

I've also got a bit of burnt oil on top of the pistons. Is this ok, can it be cleaned off?

http://i706.photobucket.com/albums/ww62 ... G_0737.jpg
http://i706.photobucket.com/albums/ww62 ... G_0736.jpg
http://i706.photobucket.com/albums/ww62 ... G_0735.jpg
http://i706.photobucket.com/albums/ww62 ... G_0734.jpg

[Turbolad]

also, any advice on what thickness gasket will i need for replacement?
My pistons are 9.0:1 and i'll prob be running 2bar boost on a gt35r - eventually!
It was a 1.2mm hks gasket that died

[mark239]

Those HKS stopper gaskets are MLS, they'll look like layers of steel, hard to see if there is actually any damage to your head gasket in your pictures, but I am looking on a mobile phone screen!!

I have the thickest one, but just because it was all that was in stock at the time!

[Turbolad]

It's a triple layer metal gasket. No holes blown but in places the layers are peeling apart.

[mark239]

mine was like that when new.

What makes you think the head gasket had gone - what symptoms?

[Mike N]

It's a triple layer metal gasket. No holes blown but in places the layers are peeling apart.

Once the headgasket has been heat cycled they should not be re-used.

On one of my Rev 1's with a cometic 1.4mm h/g, blew and looked ok as did the head, but after close scrutiny and a long straight edge on the head, the head needed a skim and cometic USA told me the gasket was fcukd. Some of the viton rubber material had come away.

The MR2 head gasket is hard enough to do, let alone repeating the process unessesarally due to a damaged head gasket, I would buy new for peace of mind.

The pistons can be cleaned up no probs.

Have you sussed the reason for the H/g failure in the first place?

Mike

[Turbolad]

so from the pics, it def looks like a failed gasket??

I'd point the blame at too much overboosting, especially at the moment of death it spiked to 2.0 bar when its only mapped for 1.5

[bobhatton]

I have never seen a metal head gasket go, check the block very well for cracks.

Bob

[Turbolad]

I'm concerned now u say that bob.
The actual symptoms I was getting. 1st I noticed the water level dropping gradually. Then at idle just after startup it sounded slightly offbeat until it was revved
Then after it went, I had lower compression on middle 2 cylinders @170psi and outer 2 @190psi. Buckets of steam coming out exhaust and crank case breather. It was definately steam not oily smoke, also had mayo all over oil filler cap, and a bit in the water pipes too. Oh and it definitely was very offbeat like it had dropped a cylinder, and it didn't overheat but started getting hotter on the very gentle drive home

[bobhatton]

That does sound like the head gasket going between the two cylinders but you should be able to see it on the gasket once its given a good clean up.
You still need to check for cracks in the bores.

Bob

[Turbolad]

i've just found a few pages that agree with what you say.
I'll double check the gasket tonight. Does the separation of layers on the head gasket not necessarily mean failure?

I had a quick check of the bores, and it still looks perfect from it's prior re-bore, but i'll re-check again tonight

[ashley]

You'd expect the gasket to actually be broken between the cylinders, I'm guessing the layers can / will seperate when you remove the head or the gasket itself.

If it has failed you should be able to see evidence of gas / water / oil flow through the layers of the gasket around / between the two cylinders concerned.

Worth checking the head hasn't warped- might explain the lack of seal between the cylinders if the gasket is in tact...?[/i]

[Turbolad]

it was almost covered in oil. I thought that part of the engine was supposed to be an oil free zone?

The head didnt pull the gasket off when I removed it, and the gasket slid off the block, so I cant see how that pulled the layers apart. Only thing I can imagine is the realese of the tension when the head bolts were loosened

[bobhatton]

The head gasket should not have slid off as there should be two locating dowels at each end of the block.
The gasket layers will come apart as they are only held together by the rivets on the edge of the gasket.

When reinstalling your head this time please use head studs and not bolts.

Your head will also need to be checked for any bows, do not just get it resurfaced as that will increase your compression ratio even higher, only get this done if the head needs it and only get the minimum taken off.

Bob

[Turbolad]

sorry, I meant the gasket lifted off with ease
It also has the arp head stud kit installed from when the engine was last built.

I dont think the head was skimmed last time, and fortunately it hasnt even got close to overheating in the 9yrs I've had the car, so fingers crossed it shouldnt have warped. but again ill check tonight

thanks for your input

[Turbolad]

I went out to double check last night, and I appear to have a crack in piston no3

[dawesy]

dang dude sorry to hear that. mine went two weeks after mapping although mine looked different and drove fine other than overheating/blowing water on boost, was fine off boost though.
this is my crack number 3 on the centre wall between 2 and 3

[Turbolad]

that's gutting that soon after mapping, I've had 2.5yrs since last mapping and about 4 since rebuild and overbore

I've read so much about cracking thinking that'll never happen, expecting a crack to be a big noticable crack that you can see fresh air thru, not such a fine hair line that ours appear to be

[greeny]

Unlucky lads!

What size bores were you running? What rev blocks?

[greeny]

...I've read so much about cracking thinking that'll never happen, expecting a crack to be a big noticable crack that you can see fresh air thru, not such a fine hair line that ours appear to be

When mine cracked, I removed the engine/head to check it, even wired brushed and cleaned the area where it was cracked and missed it! I found a hole in the hose from hell and put the leak down to that, re-installed everything, got it back to the dyno only to find it was the same!

It was easier to find the second time!