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Thread: VE blowing out headgaskets

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Posts: 1-10 of 26
2011-02-22 16:50:11
#1
VE blowing out headgaskets
Having some trouble with my new setup.

Bit of background:

Opened the motor up to change internals. Had the block resurfaced at the same time. For some reason the engineering shop took too much off the block/deck and my pistons now protrude above the deck. I used a previously used 1.6mm cometic headgasket to compensate for this and put the motor back together. The motor then overheated due to the headgasket not sealing properly. Temps were reaching 120deg celcius and I had no option but to run the car for about 40 miles to get home. Number 2 cylinder was filled with water.

Took the head off, bought a new cometic gasket. Put the motor back together. Ran ok for about 150miles whilst revs where kept below 5k rpm. Everything seemed okay, except the water would push up in the resevoir bottle if I drived a bit spiritedly, and then once the car cools down it would suck back into the engine.

Then aftger the break in I took it to dyno. On the 3rd dyno pull it blew allthe water out the resevoir in one big eruption. WE figured the gasket went out again.
Again I had to drive about 40 miles with the car getting to temps in the 100 deg vacinity most of the way.
Took the head off. Again number 2 was full of water. Also, the valvetrain was full of a milky mixture of oil an water.

So do I jsut resurface the head now and refit with another new gasket? (This is getting quite pricey and very frustrating very very fast)

Any ideas?

thanks
2011-02-22 16:57:10
#2
get a new block and a OEM 20v gasket. with that high of temps you might have warped the head to so don't for get to look at that.
2011-02-22 16:57:59
#3
My guess is that the resurface technique is lacking at the machine shop. Do they deal mostly with American V8s, or do they deal with large amount of Japanese engines?

I'd never get an SR20 block resurfaced by a shop I didn't thoroughly check out first to make sure they know how precise the resurfacing must be. And I'm pretty reluctant to resurface a modern Japanese block period.
2011-02-22 16:59:32
#4
If the head got warped then skimming it / resurfacing it should ensure it's flat again right.

Would those temps damage the block too? I don't really want to change out the block.

Where would the water have been able to get into the valvetrainto mix with the oil?
2011-02-22 17:03:33
#5
Originally Posted by Doctor
Where would the water have been able to get into the valvetrainto mix with the oil?


The cooling passages where water and oil run are usually pretty close to each other. Since you have problems with the head gasket not sealing, this is most likely what happened.
2011-02-22 17:09:20
#6
We don't really have any american V8's over here. The shop does a lot of local sr20 motors and their work is supposedly quite good.

My theory is that originally the used headgasket caused the first problem. With the motor getting hot I suspect the head might have warped causing it to repeat the blown headgasket now.

I am going to get the head resurfaced and pressure tested this week. But I need to order another d@mn 1.6+mm headgasket from the states and wait 3 weeks for it to arrive.
My main concern is that the block got damaged? Is this likely?
2011-02-22 17:11:37
#7
Sorry I cannot help you, I do not know the tolerances of our particular engine and at what temp. does high heat begin to harm the engine.

Hopefully someone who has warped a block can chime in and let you know what you are wondering.
2011-02-22 17:12:53
#8
Originally Posted by Doctor
We don't really have any american V8's over here.
Doh. South Africa. Stupid question.

Originally Posted by Doctor
The shop does a lot of local sr20 motors and their work is supposedly quite good.
Yet they took off too much material and you had to compensate with a thicker head gasket? Sounds like monkeys to me.

Originally Posted by Doctor
My theory is that originally the used headgasket caused the first problem.
Yah, used head gasket is suspect for sure.

I don't know if resurfacing the head to fix any warping is a valid solution because I don't know what happens to aluminum once it overheats. Does it warp easier now?
Anyway, if you take material off the head, you're going to have to use any even thicker head gasket now, right?
Last edited by BenFenner on 2011-02-22 at 17-30-00.
2011-02-22 17:36:26
#9
Look on the gasket, any corrosion or marks/carbon build up. You can generally see the diriction the combustion is taking when it escapes. Id also recommend pressurising the block, maybe its an issue with a leaky sleeve not seated or that dropped.

Stratton.
2011-02-22 18:07:02
#10
i say with that history of over heating the skimmimg any more work trying to get the surface level is ganna make ur situation alot more critical.... it sounds hard but i say get a new motor n be done..... its only ganna cost u more if u try to hold out hoping for the best....
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