Compression = 30psi.

[b00stedtalon2]

Did a compression test today, all 4 cylinders have 30psi of compression. Head and block are both resurfaced with a new cometic headgasket with arp's. Block is rebuilt of 1,000 miles ago and had zero problems and head is freshly rebuilt with 0 miles. The motor is also properly timed. Wtf?

I also have no way of doing a leak down test, so has anyone seen such low compression before? Any idea's?

 

[b00stedtalon2]

Took the head of, head was perfectly fine and good looking.

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BUT, my brand new Cometic gasket is basically BLACK! They should still be silver after 50k miles... It's almost like the head and block weren't even touching. The gasket is carbon fouled like a mother. It's weird because the head was decked 0 miles ago and the block was decked 1,000 miles ago.

 

[talondsp1]

My bubby had this same problem a while back. When you have the crank timing mark at TDC, is number 1 cylinder at TDC? The reason i ask, is because my friends car did the same thing. everything was new etc, but it would not start. had low compression like yours. everything seemed perfect.

But it turned out, that he had used a 7 bolt timing plate on the 6 bolt crank, and it was showing TDC on the marks, but number 1 really was 160* off or something. We put the right timing plate on, timed it again, and it fired right up. Just something you might check.

 

[b00stedtalon2]

Yeah, cylinder number 1 (and 4) are at TDC when the timing plate mark lines up. Thanks for the input though, although even if twas 160* off, my gasket still would be getting owned. The true problem is either head or block surface, or the gasket just never sealed.

 

[delta448]

Did you reuse the cylinder head locating dowels in the deck? Maybe it's possible that enough material was removed from each surface to allow the dowels to be too tall. How much material thickness was removed from head and block?

 

[wangboy925]

Your two cam gears are different, but I dont think that's an issue

 

[92awddsm]

Did you bleed the pressure off of the lifters before reinstalling the cams? I think you probably removed the head for no reason at all.

Here is a link for you. Go to the " Priming/draining the Lash Adjusters" section and follow the procedure.

http://www.dsmtuners.com/forums/articles-engine-fuel/265060-how-replace-lash-adjusters-lifters.html

 

[delta448]

did you by any chance get the block bored or honed checked the piston side to side movement and see if it does have any and if noticable plastigage it and let us know.

Never heard that before.
How do you suggest accomplishing that?

What would that even matter? The piston rings do the sealing.

I think Keith may be on to something there... but I'm still wondering how the HG got torched.