1990 XJ with 98 HO swap

I bought a 1990 XJ with a bad 4.0 motor (fist sized hole in the block) and found a good used one from a 98 Cherokee, I put all the renix accessories on the H.O motor and got it installed in my Jeep. It has a new distributor and I'm pretty sure its indexed correctly, with the #1 cylinder at TDC the rotor is lined up center with the number 1 plug wire on the distributor cap. It has fuel pressure, I can hear the pump come on and pressured fuel will shoot out of the test port on the fuel rail. It has good blue spark, I've cleaned all the grounds and connectors that cruiser54 has suggested on his site. It tries to start if I hold it to the floor and let off itll cough but just wont fire up. I've put gas down the throttle body and it still doesn't start. Just kind of looking for suggestions because I'm kind of stumped at this point. Thanks.

sounds like your distributor is 180* off. try rotating it and see what happens.

Well the distributor plug in is facing the passenger fender well and every picture I've looked at shows that that's correct, unless I'm missing something?

are you on top dead center on exhaust or intake stroke?

Cylinder one on the top of the compression stroke, "0" mark on the timing tab lined up with harmonic balancer notch, drop the distributor in with the rotor just/mostly past the number 1 distributor cap pole.

I use a compression gauge to make sure I'm getting number one compression stroke. It will make substantial compression on the compression stroke, very little compression on the exhaust stroke.

Yellow crayon works well for marking the O mark on the timing tab and marking the harmonic balancer notch.

If you go past the notch on the zero mark, back off a quarter balancer rotation and try again. The best way is to rotate the engine with the balancer bolt.

CRUISER'S MOSTLY RENIX TIPS
SETTING YOUR 4.0 TO #1 TDC
OCTOBER 30, 2015 SALAD 11 COMMENTS EDIT


With #1 spark plug removed, turn the engine over clockwise using the 3/4″ front crankshaft bolt.

You will see the degree marks on your front cover and you will see the timing mark on the balancer. Mark them with chalk or white-out.

While turning the engine over, put your finger/thumb over #1 spark plug hole. As the mark on the balancer approaches the marks on the front cover, if you are coming up on #1 TDC, pressure in the cylinder will push on your finger. If there’s no pressure, you’re at #6 TDC and need to crank the engine over until you see the marks coming together and you get pressure. Set the mark on the balancer to the 0 mark on the front cover.

They've all said it. Turn the engine over one more time with a wrench. Your probably at TDC exhaust stroke. You'll need to do this and re install your distributor.

How did you determine you were at TDC? Easy to mistake, easy fix to.

You used the 1990 flexplate/flywheel?

That's what it was y'all! Had the distributor set at TDC on the exhaust stroke on #1, turned the motor over till I felt air pushing my finger out in the #1 cylinder to TDC and re-indexed the distributor and it fired right up! Thanks for the help from everyone!

KellyBuilt said:

That's what it was y'all! Had the distributor set at TDC on the exhaust stroke on #1, turned the motor over till I felt air pushing my finger out in the #1 cylinder to TDC and re-indexed the distributor and it fired right up! Thanks for the help from everyone!

Click to expand...

Happens all the time!!