Oh crap. Engine siezed?

2001 XJ 4.0 5 speed.

Friday night I park it in my alley with the hazards on. I come back 10 minutes later. Turn the key and it makes a clunk then nothing. I try the key again and it just clicks. Me and a friend try to bump start it (pop the clutch) but the engine doesn't even turn. The wheels just skid on the ground.

I have it towed to a shop and they tell me that the motor is locked up. They try to spin the crank with a pry bar and it won't budge. They said something is broken internally. They said it would probably be cheaper to drop a used motor into it than to pull the motor and diagnose the issue.

I don't really like their answer. It was running fine 10 minutes prior to me cranking it. No leaks, misfires, oil burning or any other issues. Any ideas on what might possibly cause the motor to lock up?

lack of oil? oil pump could of broke ot ya could of broke a rod, anly way to find out is to pull the motor and tear it apart

Before you write it off, pull the plugs and see if it will turn. I've seen an injector fail and fill up the cylinder giving you a hydrolock.

Good advice from both. I didn't think to ask them if there was any oil in it. I will have them pull the plugs, then the oil pan to see if they can find the issue. Will report back.

A locked up alternator or a/c compressor will keep the motor from turning. have them pull the serpentine belt & try baring it over, with the plugs removed as stated above.

All good advice, but a shop should know to check all these things and start there first. Just my opinion there though take it as you will.

GrimmJeeper said:

All good advice, but a shop should know to check all these things and start there first. Just my opinion there though take it as you will.

Click to expand...

Well, we would like to think so, wouldn't we?

Pull the plugs, your 0331 head may have cracked and filled cylinders 3 and/or 4 with coolant.

Pull the plugs!

I just went through this with my Son's Subaru. Number 1 injector stuck open and filled the cylinder with fuel. Hydrolocked... With the plugs out, engine turned. Used the starter to pump out the cylinder, after disconnecting the coil... New injector, burned the fuel out of the exhaust, oil change and all is well again.

And yes, the cylinders could be full of coolant given the head situation.

Besides some form of liquid in a cylinder a broken timing chain could lock it up as well as a dropped valve. What about an issue with the transmission?

Without knowing what the actual cause of the problem is there is no way of knowing if it would just be cheaper to replace the engine. Might want to take it to a real mechanic instead of a part replacer.

Talyn said:

Besides some form of liquid in a cylinder a broken timing chain could lock it up as well as a dropped valve. What about an issue with the transmission?

Without knowing what the actual cause of the problem is there is no way of knowing if it would just be cheaper to replace the engine. Might want to take it to a real mechanic instead of a part replacer.

Click to expand...

x2. If you broke a rod, you would probably know. Your engine would make at least some odd noises before crapping out. I've seen 4.0's with bad rod knock run for 30k miles before it blows.

When my number 5 piston shattered and took up residence in the oil pan the engine just died. The wrist pin broke through the cylinder wall and dumped coolant into the sump. It just died but I was able to start it back up and run it on 5 cylinders. Of course it ran like crap, but I was able to move it onto the tow dolly.

Well... turns out they did remove the plugs yesterday but I wasn't getting all of the info. The #6 spark plug was smashed to shit. Even with the plugs out they still couldnt turn the motor over. They think the connecting rod broke. We still dont know what caused the problem but their guess would be an oil pump issue. The one curious thing here- the truck has been intermittently throwing a check engine light for a cylinder #6 misfire. It hasnt been on for a few weeks so I figured it was a non-issue.

This one is kind of a catch 22. Its likely that the motor will need at a minimum - a piston, connecting rod, rod bearing and a rod cap. It may also end up needing a crankshaft and a valve or two. There could also be damage to the block or cylinder head. If I pay to have the motor pulled and sent to a machine shop to be inspected just to find out that the block or head is trashed, then I am out more money. Or I can just drop in a used motor and call it a day.

Leaning towards a used motor.

just drop in a used motor yourself if you have the place and tools

Ouch.

In your case go for a used engine, get one WITHOUT the 0331 head so you don't end up with another possible problem down the road.

I'd drop in a used motor also.

91-99 are the ones you want, though you will have to do some minor fabricating to make the coil rail mount to the older head.

Ask for the old motor, disassemble it and figure out what the hell happened. Then clean the block up, slap a big chunk of tempered glass on top, and turn it into a coffee table :thumbup:

Yes, my wife loves old auto parts turned into furniture also.

I'm sure you would have no problem getting an engine block coffee table into the living room.

(I still don't know what she did with the cool ash tray I made out of the fan clutch from my 92, it seems to have just disappeared.)