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hoddie
June 4th, 2006, 20:02
Okay, I have gone through all this issues to deal with why my '91 XJ won't start. I have replaced all the starter and ignition systems, the fuel sysetm works, new distributor, cap, rotor and plugs. Still nothing. I have chased my sensors and they all have the proper ohms, volts and/or resistance.
I have come to find that maybe I should look at when it stopped and what I eventually found. When I did get around to pulling the distributor out, the teeth were ripped off of one side of the shaft.
What would cause this to happen? I have had an excesive amount of blow-by, to the point that my air filter was dripping with oil. Could this have cause the oil pump to lose pressure and cease? I turned the oil pump with a screw driver to set it up for when I dropped the distrubutor back in, it rotated without any problems. I never noticed any issues with the oil pressure guage when I was driving it. I always kept it full of oil.
The camshaft did not apper to have any damage when I checked it threw the hole. It does spin the rotor when I turn it over by hand.
So here I am. Do I have a shot oil pump, thus causing my no start? Or is my camshaft toast?
Either way I think I am going to have to rip this down or sell it for parts. I have already replaced the timing gears and chain. This is what the "mechanic" said was wrong. I thought so, until I pulled my distributor.
If anyone can help, it would be much appreciated.
Thanks,
Hoddie.

ChiXJeff
June 4th, 2006, 20:18
Check the bushing on the distributor shaft.

jcjeepnut
June 8th, 2006, 03:26
remember always -suck -squease-BANG-push. and in that order and the right time. AKA set the timing to 0 then if you have spark make sure there is injector pulse or see the crnk shft pos sensor the 4.0l will mask many problems...that isnt one of them. also remember u are still in the era of Just Everyone Else's Parts aka J'E'E'P so get to renult,delco,prestolite,dana,and others I don't speak of. u will find it if u stick to the basics. if you have a 2.8l god help u. that was a true bastard. but there still is hope.

jcjeepnut
June 8th, 2006, 03:37
sorry dude just got the rest of that steam. sheard off teeth mean somone stoped. most like the bearings in the dist. do a compression test to find why you dont fire up if u have one or more cyl. lower than 100 lbs consider game over. check your head for warpage and buy a new rotator assembly. long or short block I can help.

Dr. Dyno
June 8th, 2006, 03:50
Okay, When I did get around to pulling the distributor out, the teeth were ripped off of one side of the shaft.
What would cause this to happen? I have had an excesive amount of blow-by, to the point that my air filter was dripping with oil. Could this have cause the oil pump to lose pressure and cease?

Since you've got so much blowby, it's time to do a complete rebuild of the engine. When you tear it down, it'll be obvious which parts are worn and need to be replaced (main/rod bearings, piston rings, oil pump are obvious candidates).
The distributor itself should be OK (since it's new) and I wouldn't expect any wear in the shaft but if you reused the old distributor drive gear, it may not have been installed properly and that could be the reason why the teeth wore away. You'll need to replace it with a new gear.
The camshaft is probably OK. The gear on the cam is much harder than the distributor gear so it's very resistant to wear (the dizzy gear is the sacrificial gear as it's a lot easier to replace).
A new oil pump is a must if you decide to rebuild the engine. Maybe it's an opportunity to build it into a 4.6 stroker?