Engine no workie workie (1 Viewer)

[DaviMH47]

I'm about to pull the head on my engine build but before I do I wanted to check with the Mud Brain Trust to see if there are any ideas for my situation. I bought a 96 with a blown head gasket. Engine came out and the block and head went to the machine shop. Head was warped .045 and required replacement. I bought a remanufactured head from a machine shop on ebay. They claimed it was ready to bolt on. Fast forward to the first crank of the engine and I have no compression, numbers were 92, 50, 32, 25, 25 , 55. Wet compression test did not change the numbers. I reconfirmed timing thinking valves were open. No change. Rechecked valve clearance. No change. I attached an air connection to #1 at TDC; air was coming from the intake and exhaust.

The only thing that i can think of is that the valve job was done at the wrong angle so I'm about to pull the head and take it to a machine shop that I know does quality work.

1. Timing marks confirmed multiple times
2. Distributor alignment confirmed
3. Spark and fuel confirmed
4. Checked crank sensor resistance
5. Checked distributor plug resistance IAW FSM
6. Computer and components behind glovebox confirmed plugged in
7. Confirmed valve seals in place.
8. Grounds confirmed

Anything I should check before pulling the head?

Thanks to @matthewcruiser for the help

This is the engine before first crank

 

[NeverFinis]

Have you checked valve lash?

 

[96bruizer]

the bronze looks great!!

 

[DaviMH47]

Have you checked valve lash?

I did, everything was within spec.

 

[MMaxim]

Could the intake and exhaust cams be switched araound? I did mine a few years ago, and don't remember if this is even possible. Just a thought.

 

[Mark W]

Just off the top of my head... Beyond ignition timing, have you verified cam timing. To crank and each other? Sounds to me like vavles are not opening/closing in coordination.

Mark...

 

[NeverFinis]

I did, everything was within spec.

I would pull the cams and redo the leak down test. If it still is a problem, then it is time to pull the head.

Is valve lapping needed on 1FZ-FE? I don't know but perhaps your head needs it?

If you are willing to pull the valve springs, try machinist layout compound to check for valve to valve seat contact.

 

[DaviMH47]

The cams have stamps on them, and the ones that came with the replacement head are different than my original ones. Are they date codes? Trying to figure out if they are correct.

Anyone know?
original intake 12 BFB
Original exhaust 10 BFB
Replacement intake 7 DOD
Replacement exhaust 9 DOD

 

[mudgudgeon]

At this point with compression readings, there's only a few possibilities, i think most have been listed.
Whatever the issue is, first step is remove the valve cover.

Take your time and check and double check-

- Check valve clearance
- check cam timing
- check cams haven't been mixed up

If none of that solves the problem, you're going deeper
- remove head
- check head gasket. Extremely low compression on all 6 pots with a new head gasket seems unlikely, and suggests either a monumental **** up with the head gasket, or something else entirely)

- disassemble head and check valve/seat contact patterns. Again, all 6 totally failing to seal seems unlikely.

Hopefully you find a simple error as you dig in.

If theres nothing obvious with the top end, then look at bottom end.
If it was machined and rebuilt too, are piston rings all in place, ring gaps offset, ring gaps correct, piston size & clearance correct?
Again, seems unlikely a minor error here would result in 30ish psi on all cylinders.

 

[mudgudgeon]

The cams have stamps on them, and the ones that came with the replacement head are different than my original ones. Are they date codes? Trying to figure out if they are correct.

Anyone know?
original intake 12 BFB
Original exhaust 10 BFB
Replacement intake 7 DOD
Replacement exhaust 9 DOD

No idea. Pics?

Post pics of cam gears and timing marks?

 

[DaviMH47]

No idea. Pics?

Post pics of cam gears and timing marks?