Took compression numbers after a pretty disastrous t-belt/water pump job, and they're all pretty crappy. 35-115-35-60. I'm assuming I have some bent valves, but thought I'd just verify my timing.

Just checking before I tear the head off to look for the worst. Thanks.

Which way do the dowel pins on the cams point(can't see them because of the bolt/washers on them)

I think you half a tooth off. By the way, your t-belt is rubbing the cover.

It looks in time to me, the crank sprocket is forward a little bit which makes it look like half a tooth off. You could have one of the cams 180 out, which is why I need to see the way the dowels are pointing on the end of the cam.

The cam gears always have the 2.0 and part number stamps on the same side with the dowels facing down I believe. So if one is right side up and the other upside down, the cams are in time.

timing is fine but 1/2 a tooth off

Well I pulled the vc and I know the cams are oriented correctly - they have the holes in the 'tops' of them facing up. As far as being a half tooth off, I don't know what your definitions of a tooth are, but to me a half would be in between two teeth, not still on the same tooth. Not trying to start a flame war, but seriously if these motors are that picky about timing, then that sucks.

Still, even being that picky, would my timing be that far off to give me comp numbers like that? I'm pretty sure I have bent valves, but I'm just wanting some other opinions before I pull the head.

Nope, sounds like you have some bent valves or holes/cracks in your pistons.

Originally posted by kronus
Well I pulled the vc and I know the cams are oriented correctly - they have the holes in the 'tops' of them facing up. As far as being a half tooth off, I don't know what your definitions of a tooth are, but to me a half would be in between two teeth, not still on the same tooth. Not trying to start a flame war, but seriously if these motors are that picky about timing, then that sucks. Still, even being that picky, would my timing be that far off to give me comp numbers like that? I'm pretty sure I have bent valves, but I'm just wanting some other opinions before I pull the head.

some are a little pickier. if your head is milled or block decked then you never will be exact anyway.

Well, a little update...

Pulled the head and found this!








Uhhh, no bent valves? How the heck would I get compression readings that low if the valves weren't bent? I know it's not the rings because the motor has 148k on it and it was running like a champ before I started the t-belt service. My timing was on, we've verified that... sooo... what the heck was it?

Any ideas? I'm going to have the machine shop check out the head just in case while I wait for the top end kit.

As a side note, the only time during this whole process that the valves could have bent was during the 10 second idle period, so maybe the valves are just barely bent and not sealing? But would that give me compression readings like that?

Leak down test will tell you right? Or spray some brake clean in and see if it leaks out. Or a small amount of thin oil.

Dang man, do you sleep? Lol.

Yeah, I'm going to try the fluid test in the morning.

HAHA. Prefer not to. I would rather stay up. When my car was off the road I would stay working on it till 2-3 am.

Tried the fluid test and it looks like the exhaust valves were good. Little if any would leak out after a few minutes, the intake was not quite as good. They would all hold fluid for a few seconds, though after that a few of them would be dripping. I used WD-40 since it's pretty thin. Do you think that would be enough of a leak to give me comp. numbers like that?

And as a side note, has anyone had experience with the partsdinosaur head gasket? After shipping, there's going to be about a 30 dollar difference, and not that I'm trying to cheap out, but if I can put that $30 towards the check and deck, I'd love to. I've heard about the Fel-Pro HG which I can get at O'Reileys, and from what I've read, they seem to hold fine on these motors, but has anyone had success from the PD headgasket?

Im running a PD head gasket and its fine for me. I would think if it holds then leaks you should be ok. It has miles on it so its not going to be perfect. A little carbon can get in the way.

Thanks for the info. I just dropped the head off at the shop, so we'll see what he has to say, though I'm not too worried about it at this point.

I'm baffled by the compression results. We're you running very terribly? or at all?

Car ran absolutely fine before the teardown. But I got the head back. No bent valves, but some built up carbon had gotten into the valve guides apparently keeping the exhaust valves from closing all the way. Not sure how that happened, but he cleaned and resurfaced the head and cut all new seats for the exhaust valves.

Another off topic question: Do you guys recommend copper sealant spray on the mls headgasket?

I wouldn't use it. I never had on 2 motors and no problems. One decked head and block other no decking at all.

You don't need copper spray for this reason:

MLS gaskets are coated with 7-25 microns of elastomeric material. The resilient elastomer is essential to the structure by providing micro-sealing of metal surface imperfections while resisting aggressive combustion gases, oils and coolants at temperatures up to 250°C.(almost 500 degrees)

Copper spray is meant to do the very same thing, which is why I only ever used it on composite gaskets OR in a pinch during racing season when I reused an MLS head gasket which may have been scratched or scuffed in the hast of overnight rebuilds.

For those of you running the parts dinosaur hg, do you know if its the revised version which eliminates the need to shorten the headbolts? And if its not, should I shorten all four corners, just the two drivers side, or the on rear bolt on the drivers side?