87 wagon problems... again

superspud87

New member
my 87 wagon is just not doing good. yesterday i had to get it towed to my house because i couldnt drive it even a mere 3 miles. what happened was i pulled over to let my friend out because he had to go to work and as soon as i came to a complete stop, my jeep starting having a fit.

the whole cab was shaking so i thought that i was overheating but i popped my hood and the entire engine an everything else is shaking violently, than it died. i turned it over and it started just fine but once the rpms went back to normal it started shaking again so i opened the throttle up under the hood and that didnt do anything either and it stalled again so my 1st thought was my timing chain went out. so we towed it to my house and i checked for TDC with the 1st sparkplug removed and the rotor exposed and the timing was perfect. i talked to a few mechanics about it and they said to check my fuel filter and my coil. i checked the coil and it was emmiting an orange spark through through plug cuz i grounded it on the engine. so i got all new plugs and i checked the coil again at night and the whole firewall where it was located lit up with bright blue sparks so i got a whole new coil and this morning its still not firing up.

this is my only way to work and i have to have it fixed by tomorrow night.

any help is GREATLY appreciated...
 

update.

i just replaced the coil, new plugs and plug wires and my jeep is still not starting. i tested Top Dead Center again and it in still in perfect time. what other things can i look at to fix my jeep? the starter just keeps turning over and nothing happens
 
Make sure there's fuel in the float bowl and the needles aren't stuck assuming that it's carburated. If you have a fuel injected setup, check for a proper fuel pressure at the fuel rail. Another thing to check are your power feeds on the ignition Run position. If you get spark at the start position but dead on the run position, it will not start. I don't remember what engine you have,, i'm assuming it's a six cylinder.. The spark ultimately should be blue but when in doubt if that's sufficient, check the wiring on the coil to the firewall junction block.Check the connectors to the ignition module if equipped.if it's partially shorted to the other circuits within the harness, it will give you a weak spark or no spark at all.
 
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Make sure there's fuel in the float bowl and the needles aren't stuck assuming that it's carburated. If you have a fuel injected setup, check for a proper fuel pressure at the fuel rail. Another thing to check are your power feeds on the ignition Run position. If you get spark at the start position but dead on the run position, it will not start. I don't remember what engine you have,, i'm assuming it's a six cylinder.. The spark ultimately should be blue but when in doubt if that's sufficient, check the wiring on the coil to the firewall junction block.Check the connectors to the ignition module if equipped.if it's partially shorted to the other circuits within the harness, it will give you a weak spark or no spark at all.


ya i have the 4.0. and i am getting gas and a blue spark from all 6 cylinders and from the coil as well. and it tries to turn over but its not making any effort to actually start. my friend thinks that the timing chain could be gone but i dont want to go out and spend 80 bux unless im certain that i have too
 

ya i have the 4.0. and i am getting gas and a blue spark from all 6 cylinders and from the coil as well. and it tries to turn over but its not making any effort to actually start. my friend thinks that the timing chain could be gone but i dont want to go out and spend 80 bux unless im certain that i have too
Pull the timing cover off and check the timing marks at top dead center. That's the most accurate way to verify if the timing is off due to the loose chain. I personally never seen these chains jump off timing unless the sprocket is just severely worn out.
 
thats what I've been doing for the better part of the night. is there anyway to get the harmonic balancer off with the special tool to do so without pulling the radiator? because that would save a lot of effort and time, seeing how i need it to go to work tomorrow.

we got the fan and fan shroud off, plus the belt and the water pump and pulley, but now we really want to avoid pulling the radiator if at all possible
 

Sorry I'm late, but it sounds to me like you have no fuel happening. A spoonful in the throttlebody will test that theory in a hurry.
 
well there is in fact fuel going into the engine because we flooded the engine on accident. we got the harmonic balancer off tonight and had to call it quits due to the fact that it dropped and it me in the head and knocked me out.

but this also brings me to a few other questions, besides the timing chain, what else could cause this? i had someone tell me that it could in fact be a cracked crank and if that is the case i plan on getting a new rig.

question 2. my buddy called his uncle who has a ford 300 ci motor in his truck and he said that almost all straight six's dont have a timing chain or belt, but timing gears, my jeep does in fact have a timing chain correct?
 
well there is in fact fuel going into the engine because we flooded the engine on accident. we got the harmonic balancer off tonight and had to call it quits due to the fact that it dropped and it me in the head and knocked me out.

but this also brings me to a few other questions, besides the timing chain, what else could cause this? i had someone tell me that it could in fact be a cracked crank and if that is the case i plan on getting a new rig.

question 2. my buddy called his uncle who has a ford 300 ci motor in his truck and he said that almost all straight six's dont have a timing chain or belt, but timing gears, my jeep does in fact have a timing chain correct?

Not likely a cracked crank. It's more common to see a cracked flexplate around the flange where it bolts to the rear of the crank shaft. This will normally make some noises to indicate that. Yes, the 4.0 is a chain driven camshaft.
P.S.
I hope your headache gets to feeling a little better, it hurts me just thinking about it.:D
 

Not likely a cracked crank. It's more common to see a cracked flexplate around the flange where it bolts to the rear of the crank shaft. This will normally make some noises to indicate that. Yes, the 4.0 is a chain driven camshaft.
P.S.
I hope your headache gets to feeling a little better, it hurts me just thinking about it.:D



so, besides a cracked flexplate, or timing chain/gear issue, what else could be causing this problem?
 
well timing chain is fine. so we think that it could be a flat cam or something else. im not too incredible worried about it. check out my other post and see why its not a priority right now
 

it might be. but my main concern now is to get this new ZJ, and if i do get it im going to turn my wagon into a mudder :)
 
I'm trying to figure out how we got from an ignition lighting storm, to a timing chain, then a cam.
It's late and the old brain may not be operating on all six cylinders.
I'd back up a few steps and start over again.
If you'd like I can try and talk you through the way I'd troubleshot it. It may require you to repeat a few steps, but maybe it's better to do it by the numbers.
 
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I'm trying to figure out how we got from an ignition lighting storm, to a timing chain, then a cam.
It's late and the old brain may not be operating on all six cylinders.
I'd back up a few steps and start over again.
If you'd like I can try and talk you through the way I'd troubleshot it. It may require you to repeat a few steps, but maybe it's better to do it by the numbers.

well when it 1st broke down, my jeep stalled and died. i turned it over a few times and it would fire, than it would shut off. i towed it to my house and tried starting it again and it wouldn't even turn over. so i checked my TDC and it was right on. so i got all new plugs can rotor wires and coil, and that didnt work either. so my friend checked my tdc again with the rotor and i was about an inch off so we pulled off the timing chain cover to check it and the timing chain was newer looking. so we rewired the plug cables on the cap so it was in time so it was firing in the correct order and still its not firing. so my friend believes that its a flat cam
 

I think in all likelihood it's something else, maybe something simple. I'd check out the most common causes before I tear the motor down.
IMO it's doubtful to be either the timing chain or the cam. I've seen 4.0 run reasonably well with a timing chain so loose it contacted the inside of the timing chain cover (a couple even wore all the way through the cover and still ran OK). A flat spot on the cam is more likely to be on one or two lobes than all, a 4.0 will run without a cylinder, though poorly.


      1. Remove No. 1 spark plug.
      2. Place finger over No. 1 spark plug hole and rotate the engine crankshaft slowly until compression is felt. I usually use a compression gage instead of my finger.
      3. Align the timing index mark on the vibration damper with 0°(TDC) on the graduated timing degree scale on the timing gear cover.With the last turn being to the right as you are facing the motor (to try and take up any slack in the timing chain).
      4. Check the distributor rotor is pointed near No. 1, it won't be exactly on.
      5. Install the distributor cap and spark plug wires.

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Most times the distributor cap has a "1" molded into it, to help you find "1". The distributor has a locking tab at the base, if it has never been removed, it should be in time, the ECU corrects for timing over a really large range (in my experience you can be one cylinder off and the ECU will still correct to the proper cylinder and the motor will run, though maybe not well at higher RPM's).

All the motor usually needs to run is, air, spark and fuel. Though improper proportions of air and fuel may make it run very poorly.

Once you recheck your initial setup, we can start troubleshooting.

I re-read your last post. A couple of things to keep in mind, the leading edge (pretty wide edge) of the rotor is where the spark jumps onto the pole in the distributor cap. So the rotor is unlikely to be centered on the "1" distributor cap pole at TDC. I wouldn't pull the distributor on a hunch, it can get interesting to get back in correctly. The pin for the distributor gear has been known to shear and the rotor shaft to spin in the gear and to be out of time, but don't jump to conclusions, take it step by step or your likely to have to start all over again. You can check this by grabbing the rotor and trying to turn it with moderate force (with the motor stopped), too hard and you may break the rotor (use an old one).
 
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im going to check that on my next day off. it either could be that, or my friend still thinks that it is a head gasket issue. one way to find out for sure.
 

as far as i know yes. im not entirely sure though. why what are you thinking?
 
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