I'll try to make this long story short...
Just picked up a project truck. PO said it blew the head gasket. He attempted to fix it but never got the truck going again. Its been sitting for years. I can't get it to run...it has fuel and spark but low compression.
125 on 2 cyl
100 on the other 2.

Theoretically the thing should at least start with this compression. The motor sounds like it almost wants to start for a second and then it just sounds monotonous.

I checked the timing and it's right. Checked all fuses. Swapped in a known good ecu. I've sprayed ether directly into the cylinders but it won't fire up.

I'm looking for suggestions as to what to check next. I know my way around these motors pretty well but this one has me stumped. There is nothing obvious to me thats keeping the motor from firing up.

I have another motor to put in it but wanna try and get this one to run first.

Any Help/Thoughts would be appreciated.

 

How is the spark? Is it weak?

If you try to run it without an intake hose piece (one from filter to TB) then it won't run...at least mine won't...so make sure you put everything back together right.

 

Sounds like the problem I had getting my rebuilt 22re to fire up the first time. It would fire and try to start, than just turn over. I suspected the timing chain install.
1. Timing mark on crankshaft balancer on 0deg with compression on #1.
2. Pin on camshaft gear will be at 12 0'clock and the timing mark at 11:58, just to the left of center.
3. Pull the distributor, point the rotor at 12 0'clock, and shove it back in. The rotor will be pointing directly at the #1 plug wire.

With this method, you can't go wrong. I was one cog off on distributor. After that, it fired right up. You said you checked the timing, but.........

 

Thats what I meant by checking the timing. I made sure marks were aligned and the distributor was in right. Even tried throwing it off a tooth either way and nothing changed.

Intake tube is hooked up and tight.

Spark looks plenty hot to me.

I'm sure it will turn out to be something simple but I just cant find it right now? What am i overlooking.