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YASVT (Yet Another Sixteen Valve Turbo) - now 16V Whiteblock (LS)

Have you considered chopping that failed area out of the MLS gasket and sending it back to Cometic? Who could have possibly analyzed/root caused more failures than they have? Lessons learned could only help others, if there are any more.....
 
Have you had one fail on it's own when installed dry? What I'm reading says there are three things that are critical when installing a Cometic HG that things are very straight, very smooth and very clean.
 
They now have 'MLX' gaskets, which have a ring around the bore, that seals the layers together and doesn't rely on the layers all being mashed together enough to seal.

But they don't make them for Volvo's (yet?).

auto-head-gasket-mlx.jpg


If you look around on the interwebs I see various other pics of similar looking damage. I think it's due to insufficient clamping pressure. In this case, those intake side bolts seemed a bit easier to break loose for whatever reason. The block or head might not be quite flat there (although both got shaved at the machine shop not all that many miles ago).

I did use copper spray this time (obv from the pictures) - I could see how that could make an uncompressible, although very thin, layer that holds the head and block slightly apart when the head it torqued on, but then maybe it squirms around in use and ends up making the gasket a little loose? This time I'm def doing it dry, per Cometic instructions. Looking back at previous failures I've had it's done it with copper spray and hylomar. But not in the same spot.
 
mh.. yeah do it dry ;) just think about fluids expand under high temps.. and in copperspray is also oil.. not only copper.

i would bet it will hold without any goo between..
 
PS: In the past, I sent some pics like that to Cometic customer/tech support, never heard back from them.

At this point, I can't claim to have any sort of track record of luck installing them with something sprayed on them, not sure why I persisted in doing it. It just seemed like a good idea. Heh.
 
Dude. No one is going to judge you if you go 16v V8 cheva powa. Only I'm allowed to hold the failed 16vt boat award.
 
It's just so easy and quick to slip another HG in it. I'm gonna do that, and also start actually buying an engine and trans and putting them together. L33 and CD009.
 
JohnMc said:
It's just so easy and quick to slip another HG in it. I'm gonna do that, and also start actually buying an engine and trans and putting them together. L33 and CD009.
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But its not... Such a pain but since yours is apart then yes
 
And I'm not pulling the engine out and apart to do that. If the engine comes out it's not going back in.
 
O rings have caused more problems than they have solved in my experience. They were from a time when turbo tuning was a black art. I had a ford customer with a oringed block and could not even find a shop that does them anymore let alone could offer any guidance.

I would be suspicious of the head condition. I would check that the reveal on the combustion chambers is all the same. I have had some warped heads come through the shop that were "fixed" via a deck or decked at a slight angle. This causes the studs to bind and prevent you from getting proper clamp on the gasket. Another common issue is a head that has been annealed from over heating. The surface the stud/bolt mates to will start to mushroom out. Larger washers and machining the pads flat again is the fix there. If you need any guidance feel free to contact me at the shop. I don't get much time to spend on here anymore.
 
sdturbo said:
I would check that the reveal on the combustion chambers is all the same. I have had some warped heads come through the shop that were "fixed" via a deck or decked at a slight angle. This causes the studs to bind and prevent you from getting proper clamp on the gasket..
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Damn..... I never thought about this. Super good insight Josh, as always. :)
 
sdturbo said:
They were from a time when turbo tuning was a black art.
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They were from a time before we had MLS gaskets readily available. It was fairly cheap to just have the machine shop do it (find a good one as always) while they were doing all of the other block work.

My block has been o-ringed for 15+ years. Not pushing any serious hp through it though. Maybe 220-250hp? But it's never given me any problems. Cutting edge hg's were $200-300 back then and not easy to source. Copper hg's were... well... copper.
 
I've tried copper HG's twice, and neither time did they work at all. Once on my B20, once on the B230 (when it was still 8V). Both of them were brand new and presumably annealed how they should be, both pretty much immediately failed on the first drive.
 
The car my experience with is a folvo. Thing runs like a top until I do anything that causes it to make much more than 350~380 whp. Tune is super mild, not pushing it at all but as soon as up the torque with the tune its done. The copper gasket held more power than the fiber gaskets but it would start leaking oil/water im guessing from distorting the gasket. I suspect without orings, that car would go north of 400whp on pump gas with nothing more than a stock elring volvo gasket. I sent the car back to the customer with a mild 320whp tune and suggested he leave it there. For me the fix is a flat block with a stock gasket. I had at least 5 gaskets blow with the orings and just nothing but problems.

There is no reason to get creative here. I have customers making double this power on the same gasket and studs. Fix the issue with your head, block, or tune. My money is on the head based on what I have seen sofar. Also are you running both of the alignment dowels (sounds stupid but I have seen crazy things).
 
you are talking about these little tubes frontleft and rightrear? Whats your experience when they/one are/is missing? Now thats interesting! Thx for your post before! :)
 
sdturbo said:
I would be suspicious of the head condition. I would check that the reveal on the combustion chambers is all the same. I have had some warped heads come through the shop that were "fixed" via a deck or decked at a slight angle. This causes the studs to bind and prevent you from getting proper clamp on the gasket. Another common issue is a head that has been annealed from over heating. The surface the stud/bolt mates to will start to mushroom out. Larger washers and machining the pads flat again is the fix there. If you need any guidance feel free to contact me at the shop. I don't get much time to spend on here anymore.
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What is the 'reveal'? I'm assuming you mean looking at the way the HG aligns with the chambers, and also the way the HG aligns with the bores? To make sure there's nothing on the gasket that is unclamped?

I don't think this head was ever warped, hard to say if it was ever overheated. I had the head skimmed *very slightly* by the machine shop - the absolute minimum just to get a nice smooth refinish on it to use with the MLS gaskets. They said they barely took anything off. I did ping a bottom end half to death (cranked top rings, bent piston ring lands, pits in the head) and had the head skimmed once again (they welded up a couple of very tiny pock marks to limit the depth of the skim).

I haven't noticed any signs of mushrooming at the top of the head bolt holes, I'll check that more carefully. I remember one guy here (can't remember who) who had the top of those holes mushroom in so far that the head wouldn't come off when the nuts were removed - it was locked onto the studs still.

The block has both alignment dowels in it.
 
No the reveal is the lip between the chamber and the head surface. The most extreme example of this I have seen the valves in 1 and 4 had actually had machine marks and 2/3 were in touched due to a hack machine shop milling a warped to he'll head without pulling it apart. Not saying you did this, these heads have a life before we even start. Most of my core rejections are caused by poor machine work.
 
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