car won't start

[moe44688]

Car is 1986 dodge 600, TI bottom end, rebuilt head/turbo.

Here's some background:

Ran great but burned oil. replaced rod bearings and put on a rebuilt 782 head. still burnt oil so I got a rebuilt TIII turbo. While I had the head off, I decided to do a TII swap. after the swap, car wouldn't start. No fuel pressure and I couldn't hear the fuel pump, so I swapped the fuel pump. Now I have spark, fuel and air, but the car still won't start. It will crank but thats it. won't even pop, cough, smoke nothing. It simply cranks over and thats it.

Things I've checked and my thoughts:

I've checked timing three or four times. Used marks on the transmission housing and stall converter to bring it to TDC. Set ignition timing and lifted the distributor to make the oil pump gear was east to west, left to right. Ive had cars the were off a tooth or two and even more, they at least popped once or twice while cranking or ran like ----. So makes me feel like its not the timing.

triple check the wring swap for the TII conversion.

I unplugged the sensor right after the thermostat to see if the fan turns on and it does, so I know at least some part of the LM is good. However, some members have stated that does not necessarily mean the LM is good.

I don't even know what else to check since I have spark and fuel....

Any help would be highly appreciated.
Thanks and Happy holidays.

[tryingbe]

You need fuel, spark, and compression.

You said you have fuel and spark, check compression.

[moe44688]

Awesome, Ill check that after christmas. I appreciate the quick reply.

Also something I did not mention, after the TII swap, my check engine light never comes on, no matter what position the key is in. It does not give any codes, not even the one that comes at the end of the list. I know even if there is nothing wrong with the car, you still get one code. I'm getting nothing. Idk if this helps but I figured I'd throw it out there.

[jayspartanburg]

What kind of LM are you using?

[tryingbe]

Awesome, Ill check that after christmas. I appreciate the quick reply.

Also something I did not mention, after the TII swap, my check engine light never comes on, no matter what position the key is in. It does not give any codes, not even the one that comes at the end of the list. I know even if there is nothing wrong with the car, you still get one code. I'm getting nothing. Idk if this helps but I figured I'd throw it out there.

Check the blub?

[moe44688]

Compression was under 90 on all four cylinders. The head on the car was rebuilt by vendor said like to think its not the problem. Just did the head gasket. So that leaves piston rings??? If it was piston rings I should feel the compression leaking out where the dipstick goes right?

Ill go out and get a leak down test tomorrow anyway.

I think it is a glhs TII LM with the map sensor on the lm.

Thanks guys.

Edit:On a positive note if it is the piston rings, it would be a good time to drop it some TII pistons and rods. I can pull the pistons out the top of the motor right??

[minigts]

Under 90 on compression? That's pretty low. I'd double check that to make sure it is what you're stating. I don't know if it should do anything with such low compression, but that could be the issue. If you for sure are getting spark and fuel, compression is the only thing left. Did you plug up the TB or something when putting everything back together? Maybe you have something covered and keeping air from flowing well into the chambers. Hard to diagnose without looking at it, just thinking out loud.

[cordes]

If the compression is that low and you just swapped the head, I would double check the cam timing. Make sure the little hole in the cam is pointing up when you set it.

[HSKR]

If you have fuel and spark, and the spark is strong enough to arc the spark plug and fuel injectors are spraying then you should get at least a pop here and there. I'm thinking you need to double check that you are getting strong enough spark to light the mixture and that the injectors themselves are spraying fuel into the cylinders. Even if the timing was off with fuel in the cylinder it should try to ignite when the spark plug fires and if nothing else get a pop out intake or exhaust.

[moe44688]

Thanks for the reply guys. I'm positive nothing is blocking the TB. I had to remove a lot of the turbo/intake/IC piping to do the timing and I never put it back on. I can clearly see the TB. I'll check my cam timing one more time and see what happens, thanks for the video cordes, it will be very helpful. The spark is definitely strong enough to arc the spark plug and the injectors are definitely spraying fuel into the cylinders. I will double check my cam timing and do a leakdown test tomorrow.

[Tbird232ci]

I'm with Cordes, it sounds like you still may have the cam timing off. My SC had about 105psi of compression when I bought it. Cam timing was a tooth off and the ignition timing was WAY off. Got it all reset, and had 130psi.

A quick test is to put a tablespoon or so of oil in the cylinder and redo the compression test. If the compression increases significantly, that's a sign of bad rings. The leak down test is a better method, but I know I never feel like doing one.