Crankcase Pulley is Frozen on 2008 Jeep Wrangler X

Gatorbrown

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La Crescenta, California
Run into some bad luck with by 2008 Jeep Wrangler X. The oil pressure light came on and I drove it 1 mile further to get it home. Hoped it was a starter but not that and all pulleys can be moved except crankcase pulley. My worry is a seized engine but what is weird is that nothing catastrophic happened. It was literally driving fine with no codes, etc, and then oil pressure light came on and now this.

Hoping maybe oil pump went out and no major damage to engine. Any further diagnostic suggestions would be appreciated. :) It had been using a little oil but not major considering the age and miles at 120K. The only complication with my Jeep is that is has a Sprintex super charger on it - not sure if that was part of the problem.
 
The starter will not cause your oil pressure light to come on. Full stop.

By crankcase pulley, I assume you mean the crankshaft pulley. How are you trying to turn it? Does the engine turn over when you turn the ignition to start?

The obvious place to start with low oil pressure is the oil pump.
Drain your oil. Check for metal. An easy way to do this is with a magnet. Otherwise you can use your fingers, but be careful not to get cut. That's icky. Pull your oil filter. Cut it open. Check deep in the filter element for metal. Pull your pan. When you clean out the pan, check for metal there, too, although if the oil was clear there is unlikely to be anything here. Check the crank for signs of failure. Short of taking off the bearing caps (which means replacing the bearings anyway) about all you can do is jiggle things. If the crank or rod ends can jiggle, they're dead. If there's no metal and everything looks good, install a new oil pump. Reinstall your pan. Put a new oil filter on. Fill everything up and move on with your life.

I'd devote some time to trying to explain why you though the starter would trigger a low oil pressure warning. Because that's got me confused...
 
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The starter trail was some bad advice from a couple of junior mechanics with my son being one of them. Unfortunately, I am not much of a mechanic myself although I have now many years of experience owning cars

Tried to turn the crankshaft pulley with a large 1/2 inch ratchet. Could not get it to budge turning it clockwise. No, the engine is not turning over when I try to start my jeep.

We didn't see any metal in the oil when we emptied out. Also, pulled all of the plugs and they did not look abnormal to us. Even with the plugs all out and no compression. the crankshaft pulley would not budge.

I don't know what could be wrong to keep a crankshaft pulley from moving. We need to pull the oil pan still and also cut open that oil filter as well.

Praying that my engine will not be damaged as badly as we fear. Would like to put it all back together and keep the jeep rolling.
 
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The starter trail was some bad advice from a couple of junior mechanics with my son being one of them. Unfortunately, I am not much of a mechanic myself although I have now many years of experience owning cars
Give your son a smack upside the head. Figuratively speaking, of course.
Tried to turn the crankshaft pulley with a large 1/2 inch ratchet. Could not get it to budge turning it clockwise. No, the engine is not turning over when I try to start my jeep.
Well that's bad.
We didn't see any metal in the oil when we emptied out. Also, pulled all of the plugs and they did not look abnormal to us. Even with the plugs all out and no compression. the crankshaft pulley would not budge.
Did you run a magnet through it? It's really difficult to see tiny little metal shavings.
I don't know what could be wrong to keep a crankshaft pulley from moving.
First thing that comes to mind is that your crank bearings are gone and the crank is basically fused in place.
We need to pull the oil pan still and also cut open that oil filter as well.
Plan on pulling the heads, too.
Praying that my engine will not be damaged as badly as we fear. Would like to put it all back together and keep the jeep rolling.
At this point, I suspect your engine is dead. You've got a couple options.

1 - Drag it to a mechanic (not your son! ;) ) and have them swap in a replacement engine.
2 - Do the swap yourself. This isn't really a project for an inexperienced mechanic, so do an honest appraisal of your skills before you decide to start.

If your block is intact, you can have it machined and rebuilt. Or you can buy a remanufactured engine. Rebuilding to OEM specs vs buying a remanufactured engine cost about the same. Because you're doing the same thing the engine rebuilder already did. And it's faster to buy than build. Rebuilding only really makes sense if you're doing the work yourself (thus saving the labor costs) or if you're aiming for a significant change in performance.

If your heads are good, you can do a valve job on them, and buy a short block instead of a complete engine.

Not the news you were hoping for, I'm sure.
 
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Thank you for the great suggestions on this. I will get over to my mechanic (not son :) this time) and see what his assessment is.

Also I think I will pull off the Sprintex supercharger and sell it. I don't even need it because my off roading is mostly pleasure rides.

We will see how it comes out but I am kind of planning on the worst case being an engine swap.
 
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Thank you for the great suggestions on this. I will get over to my mechanic (not son :) this time) and see what his assessment is.

Also I think I will pull off the Sprintex supercharger and sell it. I don't even need it because my off roading is mostly pleasure rides.

We will see how it comes out but I am kind of planning on the worst case being an engine swap.
I wouldn't pull it, myself. The supercharger really isn't for off-roading. It's for getting to the trail. Your '08 has the massively powerful 200HP 3.8L. In a 4000lb vehicle that has the aerodynamics of a barn. If you're on the highway, it can use a little help.
 
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Tried to turn the crankshaft pulley with a large 1/2 inch ratchet. Could not get it to budge turning it clockwise. No, the engine is not turning over when I try to start my jeep.

We didn't see any metal in the oil when we emptied out. Also, pulled all of the plugs and they did not look abnormal to us. Even with the plugs all out and no compression. the crankshaft pulley would not budge.

I don't know what could be wrong to keep a crankshaft pulley from moving. We need to pull the oil pan still and also cut open that oil filter as well.
Take ALL the plugs out then try to crank it.