95 LT1

So I blew a head gasket, so I pulled the engine, pulled the heads, had them resurfaced, checked block for straightness, cleaned block surface, installed head gaskets, new bolts, 3 step tourqe tightening sequence, new intake gaskets, etc.

So today I have everything reinstalled and try to start, no luck.

Got fuel, got spark, no compression. I only checked cylinders 4 and 3 because the rest are almost impossible to access because of headers.

So there is no compression on either cylinder and a big puddle of gas sitting on top that can be seen sloshing when cranking. Also the valve movement can be seen when cranking.

However, if I pump compressed air into the cylinder in an attempt to find out why there is no compression, the air does not leak out.


Any thoughts on what could be going on here?


Thanks!

 

injectors hooked up with the right harnesses, all 3 wires on the starter in the right places, the pcm grounded, spark plug wires all in the right places.

 

yes all the injectors are correct and firing, I even traced them all the way back to the pcm.

yes the starter wires are connected, but there are only two unless you count the short one from the solenoid to the starter motor

yes the pcm is grounded

yes all of the spark plug wires are going to the right places and are receiving spark

I am mainly baffled as to why I am not genertating compression on cranking, but when I pump air into the cylinder it is not leaking out.

 

what is it doing when you try to start, is it sputtering at all and trying to start or just turning over?

 

it just turns over.
no sputtering

every now and then it will backfire through the intake, but that's it

 

It almost reads like your valves are adjusted way too tight.

 

that's what I am hoping. I have to pull that valve covers tomorrow.

I fabricated a tool (1/2 in drive 5/8 socket with sides ground down, the get stubby wrench on) to get all of the spark plugs out tonight and checked compression on all cylinders, 0 psi across the board. After I remembered that compression testers have a check valve in the bottom, I removed that bad boy and cannot get a cylinder to hold air either.

Any suggestion on how to properly adjust the valves assuming that the problem lies there?

 

http://shbox.com/1/4th_gen_tech2.html#adjust_valves

If this is the case hopefully your pistons didn't kiss any valves. After getting the engine running and valves properly adjusted you should do another leakdown test just to make sure.

 

Readjusted the valves and it fired right up.

The instructions on shoebox's site are much better than the service manual.

Especially this line:

"DO NOT go back and try to feel the adjustment. The lifter will immediately begin to bleed down a little. Tension on the pushrod will relax and this will make it seem like your adjustment did not work."

Originally I kepty adjusting the pushrod. Alos, the manual tell syou to add an entire turn of preload after zero lash is reached.

Thanks!

 

glad to hear it, have fun!