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I Need Flywheel/Bolts/Pilot Bearing Advice!

14K views 21 replies 5 participants last post by  crallscars 
#1 ·
I pulled the tranny the other day. Today I removed the clutch pressure plate, the friction plate, the pilot bearing, and the flywheel.

• The disc that holds the pilot bearing simply fell out of the end of the crank!
• The flywheel is a bit wavy in cross section. It needs machining or replacement.

Now the questions:

Can you reuse 4.0L flywheel bolts or do they need to be replaced?

If they *can* be reused, do they have to go back into the same holes in the crank, through the same flywheel holes? (In case this was true, I used a scribe to mark the flywheel, and I marked the bolts with a Sharpie and replaced them in the correct holes as soon as the flywheel came off.)

If I get a new flywheel is the LuK one as good as their clutch kit? (The price is right. The "Many Morons of eBay" seem to think that $468 for a Mopar flywheel is some hot deal. WTF?)

To remove the aluminum clutch housing spacer (the so-called "inspection plate") the flywheel had to come off as the guide pins stuck out far too much to allow the plate to bend enough to pop off. So the flywheel genie is now out of the bottle; I now have to re-install the flywheel when all this other work is done.

To the best of my knowledge there are no shops around here that can properly machine a flywheel like the ones we use (with a slightly domed surface). All the local shops that do this use a brake rotor mill which will make the face perfectly flat, which I have read repeatedly is not good for the TJ flywheel. So I am getting a new one. New bolts, too, I assume? The bolts are anywhere from $14 to $18 EACH! Is there a good aftermarket solution for the flywheel bolts?

Also, RockAuto lists a flywheel shim for the 2003 4.0L/NV3550 but mine does not have one. What is up with that? Do I need it? Does it go between the crank and the flywheel or the flywheel and the clutch?

I don't mind doing the clutch at all, but the flywheel was something I did not want (or expect to have) to remove. I am concerned about the pilot bearing/disc simply falling out onto the quilt when the clutch dropped off. I actually expected to have to do battle with that thing to get it out.

Any help here?

Thanks!
 

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#2 ·
bolts can be reused.. in any hole....
Dont stress the pilot bearing falling out.. You could have forced it out by wedging the main shaft back and it pulled it..
take a new pilot bearing and see if its a tight fit. inspect the main shaft end that rides in the pilot bearing.

By a new pressure plate if you think yours is bad and or flywheel.. But unless the flywheel has cracks or bad scoring, just clean it real good with brake clean and maybe take a scotch brite to it to clean it more.

looks like your rear main may be leaking.. Now is a good time to drop the pan and swap gasket.
 
#3 · (Edited)
I would replace that flywheel. It looks like it has been severely overheated. A luk one is fine. Do not have the old one machined.. Chect the fit of the new pilot bearing. It is possible that the old bearing froze up and spun the collar, fortunately, the collar is softer than the crank shaft. No problem reusing the bolts and hole locations do not matter...just make sure everything is torqued to spec, and when bolting down the new pressure plate, bring it down evenly tighting each bolt a fraction of a turn at a time.
 
#4 ·
Getting ready to do a clutch job and flywheel also if you still want to replace the flywheel bolts I found them on amazon Look up ARP 146-2801 they were $39.15 for the set
 
#6 · (Edited)
I was looking at those yesterday, actually just prior to posting this thread. Thanks for making me think of them again. I like ARP stuff on hot rods but have never used anything of theirs on a Jeep. Thanks, Titan!

I would replace that flywheel. It looks like it has been severely overheated. A luk one is fine. Do not have the old one machined.. Chect the fit of the new pilot bearing. It is possible that the old bearing froze up and spun the collar, fortunately, the collar is softer than the crank shaft. No problem reusing the bolts and hole locations do not matter...just make sure everything is torqued to spec, and when bolting down the new pressure plate, bring it down evenly tighting each bolt a fraction of a turn at a time.
Dennis, what say you about these ARP bolts, sir? Are these probably okay, or should I use the old ones? I agree about the heat damage and am worried about the entire engine, including these six bolts.

This TJ was running hot when I got it. The radiator was nearly plugged. The needle read about 3mm above the normal 210º mark (whatever temp that represents, since it is sort of a dummy gauge) and based on the condition of the jeep it probably had been like that for years. It was not running really hot, but it was a little hot for a long time. So I would imagine the bolts also might be sort of sketchy.

These ARP bolts come with a special grease for under the head (not on the threads, of course) and a modified torque value to account for the grease. The are 12 point bolts.

https://www.amazon.com/ARP-146-2801...8&qid=1488035855&sr=8-1&keywords=ARP+146-2801

Based on your okay on it I went ahead and bought the LuK LFW193 flywheel. I got it on RockAuto for like $45, which averages about $20 less than the ones on eBay.

I would clean that flywheel up before considering getting a new one.
Clean real good, After cleaning on tough looking surfaces I use a flap disk in the 80grit range. Be smooth about it and see if all those marks go away..
I would bet they do.. I seen REAL bad ones an this is far from it.
Regarding the flywheel condition:

If I run my finger from the center of the contact surface of the flywheel I feel lots of shallow valleys and a few pretty deep ones (that for some reason don't show up in the photos). It certainly needs machining, and as I said above, we have no local shop that I trust for flywheel machining: all of them use a brake rotor mill that would removed the contour of the flywheel, so a new one is needed. Thanks. The point is moot anyway since I already forked over the bucks for the LuK flywheel. Oh, well... :)

To all:

I wonder that RockAuto shows a flywheel shim for my TJ, but my TJ does not have this shim. Do I need it? I have never heard of a shim here and do not know which side it would go on; I am guessing between the crank and the flywheel, but again: I don't know.

Any ideas?

Also, since it was under twenty bucks I also got me a new pilot bearing. I know the LuK kit has one, but the one I bought has a new collar that the LuK kit does NOT have. Since the collar simply falls out of the crank I do not trust is. It is supposed to be pretty dang tight.

The question is: HOW DO I PRESS IN THE COLLAR WITH THE PILOT BEARING??? Do I simply use the same Luk tool? I am not getting this bit...
 

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#5 ·
Zero reason to change the bolts... Unless you screwed them up..

I would clean that flywheel up before considering getting a new one.
Clean real good, After cleaning on tough looking surfaces I use a flap disk in the 80grit range. Be smooth about it and see if all those marks go away..
I would bet they do.. I seen REAL bad ones an this is far from it.
 
#9 ·
I have done 1000s of these... But I can not see the surface nor can I feel it.. So if you think it is bad then get new one.. My experience allows me to work with what I got and make it work,.

drive that pilot bearing in with something like a bearing driver you can rent or brass hammer or hard plastic.. I would not use hard metal as it can deform it.
I have used Dry ice I bought at walmart.. Set the bearing on top of it and let it freeze.. It will slide right in.. But be mindeful if it dont have a collar to limit how deep, you could put it in too far.
That tool........ Is just when you begin tightening the bolts to the pressure plate.
It aligns the disc. Since the tool is not a perfect fit, I wiggle it a little as I tighten so As to center the disc as best can be. Dont have to be perfect but close is better.
check the tip of the main shaft as I said before..... you could be ****ed already..
 
#10 ·
Okay, so I am *not* getting new bolts.

I am confused about the pilot bearing. The LuK kit came only with the bearing itself. The Mopar part I just bought is the bearing already pressed into a new collar. My collar is the issue. The bearing still fits on the shaft fine and spins easily.

So, I have a new bearing and collar. How difficult will it be to press the new collar into the output of the crank? You mentioned that it might be a design where it could be pressed in too far. How can I check that? I can post photos of my output with and without the bearing and collar if that will help you tell me what to expect. Let me know and I will post some up later today.

Right now I am about to engage in mortal combat with the RMS up in the block. I have not yet pulled the bearing cap, but based on how this is going so far I am betting the seal is pretty well stuck up in there.

I hope I can get it out.

See y'all later...
 
#12 ·
It's a Jeep, not a high horse power engine unless you see a defect in the threads of the bolts, they are fine, the engine coolant going over 210 or even 240 couldn't re-temper hardened bolts. If you have spun the rear engine bearing it might have gotten hot enough, but then you have bigger problems.

Just make sure the back of the crank is clean put a thin coat of lubricant on both the crank and bearing, TAP IN GENTLY, you can use a block of hard wood and a hammer, best not to use a hammer on a bearing.

Too bad you aren't closer, I have a spare flywheel & clutch you can have.
 
#13 ·
It's a Jeep, not a high horse power engine unless you see a defect in the threads of the bolts, they are fine, the engine coolant going over 210 or even 240 couldn't re-temper hardened bolts. If you have spun the rear engine bearing it might have gotten hot enough, but then you have bigger problems.
Yeah, I figured that, but I do not want to F this up. No experience doing this sort of work, but learning fast and smiling the whole time. Until oil or dirt goes in my mouth. Or eye. :thumb:

Just make sure the back of the crank is clean put a thin coat of lubricant on both the crank and bearing, TAP IN GENTLY, you can use a block of hard wood and a hammer, best not to use a hammer on a bearing.
So it *is* a tap-in process and not something requiring a press? GREAT! I assumed that if a puller were needed a press would be, too.

Too bad you aren't closer, I have a spare flywheel & clutch you can have.
I'm good, but thanks a ton, man! :beerdrinking:
 
#18 ·
Something I have learned,

No matter how many tools you own or have on under the car with you, the one you need is still in the tool box!

A great floor jack to support the transmission & transfer case for installation is a floor jack with the little head taken off and a 12" square piece of plywood bolted in it's place.

You guys aren't making me feel any younger, I'm 64
 
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