Engine swap, Have spark, fuel, and timing, Crank No Start

[97xj_bandwagon]

1997 Jeep xj sport 4.0. I’ve run out of ideas. Had a piston explode in my old motor so I swapped in a block and kept my old head and all accessories including the distributor. Messed with the timing for a while and finally got it to where I believe it’s suppose to be (right after 1 position on tdc compression stroke). Has good blue snapping spark and good fuel pressure. I did a noid light test and can smell fuel after cranking. Replaced crank sensor, tps, ignition coil, rotor button, spark plugs, and the head. No fuses are blown. Has strong crank and sounds like it wants to start but won’t. Any advice?

[4x4JeePmaNthINg]

usually the distributor is off, did you install this with a punch? been here before lol and i thought i had it right.

are all the plug wires in the right place, and fuel injection plugs?

do you know the valve head is in good condition?

you could try starting in flood mode if you think everything else is good. pedal to the floor and crank to clear the block.

its always the little things that getcha at this point haha

[4x4JeePmaNthINg]

also how did you test to see if you were at TDC compression stroke?

[techno1154]

Originally Posted by 4x4JeePmaNthINg

also how did you test to see if you were at TDC compression stroke?

Is the distributor set to cylinder #1 or #6? I have been a mechanic since the early 1970's. Two years ago I set the distributor in my XJ to cylinder 6 i.e. cylinder 6 was ready to fire but the distributor fired cylinder 1. I dam near tear the entire 4.0 apart in an effort to find why it would not start.

[97xj_bandwagon]

Originally Posted by 4x4JeePmaNthINg

usually the distributor is off, did you install this with a punch? been here before lol and i thought i had it right.

are all the plug wires in the right place, and fuel injection plugs?

do you know the valve head is in good condition?

you could try starting in flood mode if you think everything else is good. pedal to the floor and crank to clear the block.

its always the little things that getcha at this point haha

I did the punch trick. With the oil pump line thing at 11 o’clock, I positioned the hold down bracket at 1 o’clock and it would end up slightly past the bolt hole in the block. I tried multiple times to get it to line up perfectly with the hole but it was always ending up slightly past it so I would take the punch out twist the distributor to line up with the bolt hole.

[97xj_bandwagon]

Originally Posted by techno1154

Is the distributor set to cylinder #1 or #6? I have been a mechanic since the early 1970's. Two years ago I set the distributor in my XJ to cylinder 6 i.e. cylinder 6 was ready to fire but the distributor fired cylinder 1. I dam near tear the entire 4.0 apart in an effort to find why it would not start.

The rotor is pointing to the 5 o’clock position at cylinder 1 tdc compression stroke.

[97xj_bandwagon]

Originally Posted by 4x4JeePmaNthINg

usually the distributor is off, did you install this with a punch? been here before lol and i thought i had it right.

are all the plug wires in the right place, and fuel injection plugs?

do you know the valve head is in good condition?

you could try starting in flood mode if you think everything else is good. pedal to the floor and crank to clear the block.

its always the little things that getcha at this point haha

Plug wires are in the right spot along with the injector wires
The head seems to be in good condition.
I’ve cranked with the pedal down and i can hear cylinders firing but it won’t turn over

[97xj_bandwagon]

Doing a compression test tomorrow. I couldn’t get a reading on the old head and it had some damage on the cylinder 6 valves from the piston exploding so I went ahead and replaced it.

What is the minimum compression these things need to run???

[BALTANAKT]

If you have spark and fuel it has to be your timing.

[97xj_bandwagon]

Originally Posted by BALTANAKT

If you have spark and fuel it has to be your timing.

That’s what I’m thinking.. But I can’t figure out how to get it to line up perfectly with the punch method. If the compression checks out good tomorrow then I’ll definitely go after timing.

[RCP Phx]

You never answered about how you determined #1 TDC?

[RCP Phx]

I will add that we call my brother-in-law 180 Ray for 40yrs, he has never stabbed one right the first time!

[97xj_bandwagon]

Originally Posted by RCP Phx

You never answered about how you determined #1 TDC?

Pulled the valve cover off and when the intake valve opened I continued to the 0 mark.

[97xj_bandwagon]

Originally Posted by RCP Phx

I will add that we call my brother-in-law 180 Ray for 40yrs, he has never stabbed one right the first time!

I did that when i first put it in and it was shooting flames out of the intake lol.

[techno1154]

Originally Posted by BALTANAKT

If you have spark and fuel it has to be your timing.

Originally Posted by RCP Phx

I will add that we call my brother-in-law 180 Ray for 40yrs, he has never stabbed one right the first time!

Originally Posted by 97xj_bandwagon

I did that when i first put it in and it was shooting flames out of the intake lol.

It is difficult to say whether or not the head is good but I am with the above quotes,... it have to be timing.