Well The Joy has Ended...Bent Flexplate? Not Sure! - Jeep Cherokee Forum

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Well The Joy has Ended...Bent Flexplate? Not Sure!

Old 02-07-2019, 07:56 PM
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Unhappy Well The Joy has Ended...Bent Flexplate? Not Sure!

So my 2 weeks of joy has ended in typical fashion. Potential expensive destruction. Soo I had experienced this chug chug situation with a slight knock while in drive at stoplights and what not. I know my truck and I know what its like to have multiple situations similar to that...exhaust leaks, low on oil, crappy idle. Well I do not have any of those. My jeep idles perfect my exhaust leaks but not enough to do knock with almost a metal sound...And my oil is solid. Anyway today the chug took on a new level of loud. I had pulled up at work and while getting ready to put the jeep in park I was holding the brake in drive and the knocking became really loud...definitely like a metal knock and I know it is the dam flywheel. I already read posts and previously checked the flexplate bolts...they were super tight but it did look like the flexplate was slightly unbalanced//this was a month ago during the bolt inspection I checked while the engine was running. The Knocking goes away in park and the idle is always solid but I can feel a little shimmy. Sad to say I did some research and none of it made me feel good. Well my mechanic is gonna check it on Monday since they installed the engine they could have messed it up when it got mounted. That is a pain in the butt job and to me I felt the engine was shifting on the mounts...so I dunno. Maybe there is a chance. So She is gonna sit again. No way am I driving with a knock that hard. The starter has no problem with the flywheel and she shifts and drives great...this is when you are holding the brake while in drive. The reason I think the engine is moving is cause I hit bumps and think that makes the difference. Insane. I am not touching this one but if you have ideas for me to give my mechanic let me know. He does transmissions and engines no problem....I think this problem falls on him since he did the engine swap....OYe. my best friend. So the Saga continues...was hoping it lasted longer.
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Old 02-08-2019, 02:04 AM
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Dang brother - that sucks.

I wonder if your buddy's torque wrench might be out of whack and the engine to tranny bolts and corresponding mounts' bolts are loose...
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Old 02-09-2019, 11:24 AM
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Originally Posted by PatHenry View Post
Dang brother - that sucks.

I wonder if your buddy's torque wrench might be out of whack and the engine to tranny bolts and corresponding mounts' bolts are loose...
I can only hope that's it!

It is pretty specific knock....close to a hammer hitting metal. Does not do it while the engine is idling in park....does not do it in reverse...does not do it while you are driving, brakes off.
This only happens when you are in drive holding down the brake. Stop signs, stoplights, etc. And it does not always happen! Sometimes it is a little and other times you think Thor is under the dam Jeep.
So that leads me to think besides the flywheel being slightly warped...the engine is moving or the trans is moving...Well dropping it off Monday so we shall see.
Unbelievable...I jinxed myself in my previous thread of joy and happiness.
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Old 02-09-2019, 01:02 PM
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Never seen bellhousing bolts come loose or even seen someone torque them and highly doubt that Is it. Doubt itís your flywheel as well . An engine knock will present itself a lot more under a load aka ď in gear ď vs in park . Do a thorough visual inspection ! Howís oil pressure ?
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Old 02-09-2019, 01:19 PM
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Originally Posted by GreaseMonkey17 View Post
Never seen bellhousing bolts come loose or even seen someone torque them and highly doubt that Is it. Doubt itís your flywheel as well . An engine knock will present itself a lot more under a load aka ď in gear ď vs in park . Do a thorough visual inspection ! Howís oil pressure ?
Yeaahhhh well I am gonna have to go ahead and disagree with you Brother. It is not an engine knock...my oil pressure is fine. This is the replacement engine...I know what real engine knock sounds like. And it is the flywheel...I saw it running myself when I checked the flexplate/flywheel bolts...the dam thing is spinning offset. At the point when I checked it, it was not that bad. Now I think it is becoming bad. Do some more research....those flywheels can go on 90's cherokees.... anyway I do appreciate your input but disagree 100% about pointing to the engine
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Old 02-09-2019, 03:13 PM
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I've seen loose bellhousing bolts, usually after someone installed without properly torquing them or had something pinched between the engine and bellhousing. Cracked flexplates are somewhat common, and can usually be diagnosed with a mirror a flashlight after taking off the inspection cover (the one you removed to check the plate to t/c bolts).

Have someone hold the brake in drive while you inspect. It could be lots of other things like the exhaust hitting, bad tranny mount, etc.
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Old 02-09-2019, 03:21 PM
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Originally Posted by lawsoncl View Post
I've seen loose bellhousing bolts, usually after someone installed without properly torquing them or had something pinched between the engine and bellhousing. Cracked flexplates are somewhat common, and can usually be diagnosed with a mirror a flashlight after taking off the inspection cover (the one you removed to check the plate to t/c bolts).

Have someone hold the brake in drive while you inspect. It could be lots of other things like the exhaust hitting, bad tranny mount, etc.
Thanks man. I knew I was not the only one. Well I am gonna put this on my mechanic buddy unfortunately cause he did the engine swap. Anyhow Monday or after we will know for sure. Just hopin it can be resolved without too much insanity. The Jeep is teetering on the edge of perfection with the motor and trans,,,,but alas. Twas not to be. I will never work on making it pretty/manly until all mechanical sht is fixed....thanks for the post!
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Old 02-09-2019, 03:36 PM
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Ok I suppose bellhousing bolts can be left loose by an amateur but I certainly never have . It is hard to diagnosis from words on the internet and in my years as a mechanic Iíve only seen a few busted flex plates ... so thatís why I said that . Maybe itís way more common with 4.0s than I thought but I thought the primary thing to happen is for the converter bolts to be loose . However in my experience they still made noise in park as well with a broken flex plate . A video would help ! Iím in middle of installing a transmission as we speak.
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Old 02-09-2019, 04:25 PM
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Originally Posted by GreaseMonkey17 View Post
Ok I suppose bellhousing bolts can be left loose by an amateur but I certainly never have . It is hard to diagnosis from words on the internet and in my years as a mechanic Iíve only seen a few busted flex plates ... so thatís why I said that . Maybe itís way more common with 4.0s than I thought but I thought the primary thing to happen is for the converter bolts to be loose . However in my experience they still made noise in park as well with a broken flex plate . A video would help ! Iím in middle of installing a transmission as we speak.
To be honest I thought it would make noise in park also. But I guess when you engage the transmission the flexplate comes in contact with something...I dont think this is the Cps sensor cause it is enough to shift the whole vehicle while holding the brake. And yes I have read stories where guys bought new flexplates and they came warped(china crap) but I am not sure what it is hitting at this point. I work a lot and get tired so my evening research has too much beer. But I have been so far up this trucks *** you could see my face come out the Oil Cap. Anyway...to sum up...engine=good trans=good connection between them=no good. So Dear baby jesus...please help my cherokee get back to normal,,and please bless this meal of KFC, taco bell, dominoes, and pepsi....Amen.
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Old 02-09-2019, 04:43 PM
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Originally Posted by DCWinterXJ View Post
To be honest I thought it would make noise in park also. But I guess when you engage the transmission the flexplate comes in contact with something...I dont think this is the Cps sensor cause it is enough to shift the whole vehicle while holding the brake. And yes I have read stories where guys bought new flexplates and they came warped(china crap) but I am not sure what it is hitting at this point. I work a lot and get tired so my evening research has too much beer. But I have been so far up this trucks *** you could see my face come out the Oil Cap. Anyway...to sum up...engine=good trans=good connection between them=no good. So Dear baby jesus...please help my cherokee get back to normal,,and please bless this meal of KFC, taco bell, dominoes, and pepsi....Amen.
i would personally check the LH engine mount with a mirror, as the rubber perishes,

at least 3/4" between TX and xmember,

check bellhousing bolts,

pop a dial gauge on flexplate, crank motor with a socket on HB bolt
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Old 02-09-2019, 05:23 PM
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Originally Posted by DCWinterXJ View Post
To be honest I thought it would make noise in park also. But I guess when you engage the transmission the flexplate comes in contact with something...I dont think this is the Cps sensor cause it is enough to shift the whole vehicle while holding the brake. And yes I have read stories where guys bought new flexplates and they came warped(china crap) but I am not sure what it is hitting at this point. I work a lot and get tired so my evening research has too much beer. But I have been so far up this trucks *** you could see my face come out the Oil Cap. Anyway...to sum up...engine=good trans=good connection between them=no good. So Dear baby jesus...please help my cherokee get back to normal,,and please bless this meal of KFC, taco bell, dominoes, and pepsi....Amen.
ha ha Post of the day !
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Old 02-09-2019, 05:30 PM
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Originally Posted by awg View Post
i would personally check the LH engine mount with a mirror, as the rubber perishes,

at least 3/4" between TX and xmember,

check bellhousing bolts,

pop a dial gauge on flexplate, crank motor with a socket on HB bolt
I am giving this debacle to my mechanic/good friend who did the engine swap. he is a smart dude so I think he is going to be extra thorough since I put him through the ringer the last time. I will find out Monday. Do you think it is beneficial to tell him this stuff? I mean he has done tons of engine swaps...he did my chevy express 2500 van and she is still a beast...I dunno. It may snow in Jersey tomorrow and of course I put my jeep in the shop and use my Altima. I gave up at this point anyway. We have not had real snow the entire season. And the Jeep was always being work in progress. F it.
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Old 02-09-2019, 05:32 PM
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Originally Posted by GreaseMonkey17 View Post
ha ha Post of the day !
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Old 02-09-2019, 05:35 PM
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Are you sure the insulator hasn't collapsed/rotted away allowing the exhaust pipe to contact the cross member?
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Old 02-09-2019, 08:40 PM
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Originally Posted by Turbo X_J View Post
Are you sure the insulator hasn't collapsed/rotted away allowing the exhaust pipe to contact the cross member?
For reals man that sht broke forever ago..of course the exhaust is hitting the cross member. Has been since the beginning of time itself/or my ownership. But yet no that is not the problem. If it was I would not cry myself to sleep at night with a bottle of rum. But thank you for your speculation. I am tired. Have a date with rum and tears.
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