Head gasket swap.... won't crank now... 150 psi compression...Vortec 5.7

[redfishsc]

Amidst all this sinus infection I've been trying to get this truck to start. I'm stumped--- this isn't the first head gasket job I've done on this generation 5.7.

This is a 99 Suburban... one of the two I own. I did this same job to the other one last year, didn't run into this issue. I'm sure it's something I've done wrong or overlooked.

After everything was bolted together, I was able to crank it but it ran TERRIBLE (misfires, but no backfires). Assuming I had the distributor installed wrong, I pulled it and reset to TDC compression #1 following http://www.gmtruckcentral.com/articles/distributor.html

After reinstalling the distributor, it wouldn't even fire. Felt like either no spark or no fuel. At that point the sinus infection won the day and I shut down the garage for the week.


So here is where I am at now:

• Cyl heads are both fresh remans from a reputable machine shop.
• Battery is charged.
• Plugs, wires are new Delco. Dist cap is Delco, clean, 6 months old.
• Plug wires are to the correct cylinder.
• Ignition coil/control module works properly (I removed it and put it in my other truck, which ran fine).
• I've checked for missing connectors.
• Fuel injectors aren't mis-routed. I was careful to follow the included guided and double-check my work before installing intake.
• Fuel injectors seem to be working--- I get fuel in the cylinders if I pull the plug but leave the fuel pump powered up.
• Distributor was set to TDC compression #1, although tomorrow I'll go re-check it.

The only two things I currently can think of:

• Bad valve adjustment? I installed brand new lifter (Enginetech brand) and they said to adjust them 1.5 turns past 0 rod lash. That sounded kinda harsh to me so I did 1.25, which I am suspicious was STILL too much.
• Compression on all 8 cylinders ranges from 148-158. I'm glad they are consistent but it seems low.

Tomorrow I will check again that the truck is on TDC #1 compression with the distributor in the right position. If that doesn't work, should I pull the valve covers and back off each nut by about 1/2 turn, which would put me back to the normal factory spec of 3/4 turn past 0 lash?

 

[redfishsc]

Well gentlemen i got her running. I did have the distributor 180 out, which makes me a total fumblebuck.

First time, I had it set to TDC compression #1 accurately because I set it that way before putting on the intake manifold, were you could see the valve lifters. But I put the distributor in one tooth off.

Second time, I just did a terrible job of locating TDC compression number one.

If anyone wants to know an easy way to one-man locate top dead center compression for number one, here's what I did.

I hooked my compression gauge up, except I did not put the actual gauge itself on. I plugged a rubber hose to the end of, then the other end of it over into a jar of water. When rotating the engine with a ratchet on the harmonic balancer nut, you'll start hearing the bubbles gurgling up before the timing mark arrives in place. If I have to do this ever again, this is exactly what I'm doing. Was by far the easiest I've done yet.


150psi compression sounds low but the truck runs better than it has in the past 3 years Ive had it.

I hear the valvetrain more than I remember but its subtle and it idles and revs slick as glass

 

[grampadirt]

Pretty clever on finding TDC,I'll be remembering that for future use

 

[redfishsc]

You probably don't even need the compression hose if you have a hose that would stuff right into the spark plug bore enough to seal it up.


Yeah I'm definitely going to remember it lol. The bubbles start singing long before the marks line up so you don't accidentally advance past it