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Blown engine?

Since you have the plugs out and the serpentine belt off, try turning over the motor by hand. It should be fairly easy, just use a socket on the crank pullet bolt and see how hard it is. If you can turn it by hand fairly easily, it is definetely an electrical problem. If you have to struggle to turn it (with no plugs in it), then it is time to look for the source of the bind.
 
It is not electrical. I cant even turn it by hand with no plugs and belt. Where to look now?
 
Have you tried to turn it the opposite directions?

Can anyone confirm if the motor is an interference fit motor?

I'm assuming its a 4.0L I6?

If it is an interference motor and the timing chain broke, the piston would hit the valves and come to a dead stop, the piston would be jammed against the valves and unable to move. If this is the case, you may be able to turn the motor in the opposite directions and move the pistons away from the valve, other pistons will hit other valves eventually, but if you can rock the crank back and forth between a certain range that narrow the cause down a little.
 
Rick Anderson said:
Have you tried to turn it the opposite directions?

Can anyone confirm if the motor is an interference fit motor?

I'm assuming its a 4.0L I6?

If it is an interference motor and the timing chain broke, the piston would hit the valves and come to a dead stop, the piston would be jammed against the valves and unable to move. If this is the case, you may be able to turn the motor in the opposite directions and move the pistons away from the valve, other pistons will hit other valves eventually, but if you can rock the crank back and forth between a certain range that narrow the cause down a little.
Click to expand...
I don't think it is, and that makes lots of noise when it happens.
 
XJjosh said:
Ok, so today I was driving down the street and my engine shut off. My oil pressure was fine and there were no noises or symptoms before it happened. I took the serpentine belt off and made sure no pulleys were locked up. then tried cranking it over by hand but it was stuck.
Click to expand...

It sounds like the timing chain has skipped several teeth altering the cam timing and the pistons have hit the valves. The question is why? It's extremely unusual for the timing chain to break altogether so either the chain itself was overstretched and became too slack, or the black plastic "tensioner" thingy inside the timing cover just wore away. You surely would have had some advance warning of this problem in the form of timing chain rattle at idle and low revs.
Since you can't turn the crank clockwise, try turning it counterclockwise. It won't move at all if the engine's seized but it'll move a few degrees if it's a timing chain problem. To find out if the timing chain is broken, remove the distributor cap and observe the rotor as you turn the crank CCW. If the rotor doesn't move (the distributor is driven by the camshaft), that'll confirm it.
Unfortunately if that's the case, it's a sure bet that you'll have at least two bent intake valves and you may also have two bent exhaust valves in the same cylinders (because two pistons will be at TDC), so the head will have to come off for inspection. You'll probably find two damaged pistons and the decision to replace them will depend on how badly they're damaged. If you need to replace two pistons, it'll make good sense to replace the piston rings on all the pistons while you're there. That way you won't have to worry about oil consumption and blowby in the near future, and you'll be replacing the valve stem oil seals anyway.
 
I have a 2001 with no distributor. I cant turn it clockwise or counter clockwise. I never had any rattles, ticks, anything.
 
In that case... I'll bet the crank bearings are seezed!! If the crank locks, thoretically it could just "quit" like it did without any other noises.

NOT an easy check, or un-expensive should you screw it up. Drop the oil pan, loosen the bearing caps a "smidge" and try to turn the crank. Perhaps you'll even see the issue.
 
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XJjosh said:
I have a 2001 with no distributor. I cant turn it clockwise or counter clockwise. I never had any rattles, ticks, anything.
Click to expand...

In that case it would seem that the engine's seized. Pull off the oil pan and inspect the bottom end. I'll be surprised if you don't find anything abnormal.
 
The belt is still off. All the pulleys turn freely. I am gonna take off the oil pan first i think and see whats going on.
 
Ok, I just drained the oil and everything is ok. No metal shavings. I also pulled the valve cover and everything looks good there. I cant get my exhaust off to take off the oil pan to check the inside of the bottom end. What should I do next?
 
Lift the front end and keep on jack stands. (stands right behind the LCA mounts) Disconnect the top nut on your shocks, pull the front tires and let the axle droop. You should have enough room then to remove and work out the oil pan. BE CAREFUL of the oil pump as it hangs into the body of the pan. You can always remove the sway bar and pop the steering stabilizer to give you more clearance to work it out of there.

Consider this pre-training for changing a rear main seal!!! It's best to have an inch pound torque wrench if you don't have one as the 2 sizes of bolts holding the oil pan on need very little torque to be tight. (when reinstalling IF needed)

You don't need to remove the head pipe at all.
 
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I dont have a problem with the front end....I cant get the bolts loose to seperate the exhaust collector!
 
XJjosh said:
I have a 2001 with no distributor. I cant turn it clockwise or counter clockwise. I never had any rattles, ticks, anything.
Click to expand...
Is this you can't turn the motor by the crank or turn the distributor/cam sensor? Since you have your head off, do any of the pistons look damaged? Any valves bent or not seating? Nect step might be to take off the front cover/ timing chain cover. I'd try and turn the crank with a breaker bar and socket on it. If the pistons move OK, then I might think the cam sensor might be bad. The front ocver is fairly easy to take off and install. With the head off you should have already taken off all the brackets for the belt/ accesory drive.

Tom
 
I havent taken the head off, just the valve cover. And I cant turn it over by the crak with a breaker bar. What should I do next?
 
Looking at your FSM, you may need to remove the exhaust. Soak the bolts with some PB Blaster and wait an hour or so, come back soak again and give it a try.

Josh... PM Martin or Eagle for some good "driveway advice." They are 2 of the best!
 
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