WARNING: All 4.0 owners check your motor mount/block Bolts!!!! - Page 7 - JeepForum.com
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Unread 10-30-2011, 06:59 AM   #91
mbardeen
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1995 XJ Cherokee 
 
Join Date: Sep 2011
Location: Talca, Maule
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Reading through this thread got me worried about my own bolts, so I went and checked and it appears like I have studs holding my lower mounts on to the block. Should I still be worried, or does this mean they've alread been replaced?

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Unread 10-31-2011, 06:02 PM   #92
BrunoS
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studs means the bolts have been removed.

check the nuts/lockwashers anyways.

my repair has held, 190k miles now.
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Unread 10-31-2011, 08:21 PM   #93
alleyoop
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Thanks for the thread. I checked mine, and are intact, but I've been getting a slight "clunk" when I stop, as if something is binding. I note the left engine mount is suspect for moving upward slightly under load, but is intact. Does the rubber wear and allow the metal to move some? Do I need a new mount there? That one looks like a bugger to get to. Any tips and tricks?
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Unread 11-01-2011, 05:32 AM   #94
RussellRussXJ
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I agree with most posts in this thread. I felt a wierd shake in the Jeep, pulled over to check it out and there it was, broken bolts in the block for the engine mount. It was a Nightmare to repair but got it done. By far the worst experience with the Jeep yet.
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Unread 11-01-2011, 07:07 AM   #95
mbardeen
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Quote:
Originally Posted by alleyoop View Post
Thanks for the thread. I checked mine, and are intact, but I've been getting a slight "clunk" when I stop, as if something is binding. I note the left engine mount is suspect for moving upward slightly under load, but is intact. Does the rubber wear and allow the metal to move some? Do I need a new mount there? That one looks like a bugger to get to. Any tips and tricks?
I just replaced my frameside motor mounts with brown dog mounts. Took about an hour or so to do. Passenger side is a bit tight, because of all the stuff in the way, but I was able to squeeze the old mount out and new mount in under the AC lines.

This is what my driver's side mount looked like:


Passenger's side mount was in better condition.
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Unread 11-01-2011, 04:25 PM   #96
slaystrends
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Anyone with 98' or later models have this problem? I have a 2000 and just wondering how common it is for 98'+........
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Unread 11-01-2011, 05:52 PM   #97
MckayMan
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Hahaha funny this pops up again. Just ordered brown dog's (rubbery ones). After installing the headers with the intake manifold not aligned right, causing engine to explode to red line right when I started it. I figured it would be for good measure to go ahead and replace the mounts.
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Unread 11-01-2011, 07:23 PM   #98
sean2857
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This just happend to a friend of mine. Turns out 2 of the bolts were lost and 1 sheered off in the block. That isnt the bad part though. The stress caused the block to crack slightly. Its not leaking any fluids but it must be removed to repair the damage.
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Unread 11-05-2011, 04:37 PM   #99
Kasia
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Mine's also a 94, 4.0 5-speed. Figures I find this post 6 months after dealing with this problem on and off; mine just broke for the 3rd time on the passenger side, after the first time only being able to get 2 bolts in (the 3rd was broken off long before i had the truck im guessing, since it's rusted), and the second time only being able to get one bolt in. Of curse I used all grade 8 bolts, and 2 have a bit from a cheap easy-out broken off in them... but im gonna try and work on it again.

One problem I've had is getting a drill in there (I have the smallest 90 degree drill i could find); i can just fit it on an angle to get to the bolts (probably why the bits broke off), and the top one i can't get to at all; would it be safe to drop the mount on the other side as well, or would that make any difference? and is there anything I'd have to watch out that im dropping it on (other engine components).

I know someone in here said about dropping the trans case, trans, and motor all together, but im hoping to find something a little quicker.
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Unread 11-05-2011, 07:19 PM   #100
Xjoutsider
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I dropped the drive train down as one unit took like an hour to do. The used a dermal a drill, arch welding rod to get the bolts out
To to lower it I used a trans jack an a floor jack
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Unread 11-06-2011, 01:05 PM   #101
Kasia
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Well, none of them are coming out.... for those of you that took it to a shop, approximately how long did it take and how much did it cost? the labor rate around here is 85.00 an hour, so I'm kind of nervous about taking it to a shop since I only got a hundred or two to spend.
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Unread 09-01-2012, 12:29 AM   #102
mikegoat
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engine mounts - damn thing

I know this thread is a bit old but thought I'd add my 2c. On Thursday evening I went over a speed hump on the way into a restaurant and a 'pop' followed by engine vibration. Wife went ballistic, of course (like it was my fault) when I suggested the engine had partially separated from its mountings. Limped it twenty miles home nice and easy, keeping the revs in the sweet spot (it was still being held by the pax side mount) and took it into the mechanic in the morning (needed to do the 90mi to work but unfortunately missed out!). I'll usually attempt to do things myself but as the engine had fallen slightly and needed jacking up *and* it's tough to get in there, I thought I'd best admit defeat. It took the guy over three hours to drill out the sheared bolts and replace them with grade 8's. Unfortunately he couldn't get one of the bolts out even using an easy out, and this makes me nervous. I'm thinking of either getting it tacked on (I know it'd make maint. in the future harder) or getting it bored out a bit and using a heliarc. In the mean time I'm one bolt short and on a wing and prayer! Looks like my $$ set aside for getting current for my PPL again (after a 5+ year hiatus) and modding my android Jeep mp3/nav project has taken a big hit. (labor was about $350 and it's not over).. The only 'good' news is the oil leak that has developed, which I just assumed (from prior Jeep experience) was the rear main seal is actually coming from the 45-degree oil filter adaptor on the 95XJ - so a fresh gasket will solve that.

In this economy any unexpected expenses suck so I feel all y'all pain. Mine has almost 150,000 miles btw. 4.0 still going strong. Propane conversion is next big mod considering price of gas where I am (Aust.)
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Unread 09-01-2012, 01:02 AM   #103
skid2964
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1995 XJ Cherokee 
 
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You can buy a set of motor mounts that bolt to several other bolt holes on the engine, thats how I fixed mine. I will see if I can find where to order them and post soon...

Quote:
Originally Posted by mikegoat View Post
I know this thread is a bit old but thought I'd add my 2c. On Thursday evening I went over a speed hump on the way into a restaurant and a 'pop' followed by engine vibration. Wife went ballistic, of course (like it was my fault) when I suggested the engine had partially separated from its mountings. Limped it twenty miles home nice and easy, keeping the revs in the sweet spot (it was still being held by the pax side mount) and took it into the mechanic in the morning (needed to do the 90mi to work but unfortunately missed out!). I'll usually attempt to do things myself but as the engine had fallen slightly and needed jacking up *and* it's tough to get in there, I thought I'd best admit defeat. It took the guy over three hours to drill out the sheared bolts and replace them with grade 8's. Unfortunately he couldn't get one of the bolts out even using an easy out, and this makes me nervous. I'm thinking of either getting it tacked on (I know it'd make maint. in the future harder) or getting it bored out a bit and using a heliarc. In the mean time I'm one bolt short and on a wing and prayer! Looks like my $$ set aside for getting current for my PPL again (after a 5+ year hiatus) and modding my android Jeep mp3/nav project has taken a big hit. (labor was about $350 and it's not over).. The only 'good' news is the oil leak that has developed, which I just assumed (from prior Jeep experience) was the rear main seal is actually coming from the 45-degree oil filter adaptor on the 95XJ - so a fresh gasket will solve that.

In this economy any unexpected expenses suck so I feel all y'all pain. Mine has almost 150,000 miles btw. 4.0 still going strong. Propane conversion is next big mod considering price of gas where I am (Aust.)
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Unread 09-01-2012, 06:04 AM   #104
cruiser54
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Has this been posted i this thread yet? The REAL cause? Tightening the bolts doesn't solve the issue.

From Jon Kelley aka 5-90 @ www.kelleyswip.com



This is a known issue.

1) Unless you're going to get silly with the skinny pedal, 2xSAE8 screws on one side won't be a huge problem. You'd be better off with three, but if you don't get silly you'll be okeh.

2) The Brown Dog engine mounts use two or three additional holes on each side, and spread the mount/clamping force over more of the block. This is invariably a good idea, and I'll probably be doing it as I refit my 88.

3) The primary reason that the screws snap is because, sometimes, the screw holes in the block aren't drilled & tapped deeply enough. This causes the screw to bottom out in the hole, so you end up torquing against the bottom of the hole instead of stretching the screw (as you're supposed to do. Not your fault - you aren't doing anything wrong.) The screw is not stretched properly, and the head is not butted up against the bracket, so there's some room to move there. Vibration then causes wear cycles on the screw, which generally leads to rupture.

The easy/cheap fix? When you replace the screws (3/8"-16x1.25", as I recall,) put two flat washers under the head before you screw it into the hole.

The check? Take a feeler gage (.003" to .005") and try to slide it under the head of the screw. You'll be able to get under the corners (look at the hex head, and you'll see that the surfaces curve toward each other slightly) if it's a standard hex head - if it's a flanged hex head, you should not be able to get under the head anywhere. If you can slip the gage under the head, you have a problem. If you can touch the shank of the screw, you have a big problem!

In no case should you reuse the screws after you take them out - they'll be stressed under the head, and you'll have a significant reduction in strength. Replace them outright, putting washers under the head as I mentioned before. The washers will make up for the slight lack of depth in the hole (two of them will be about 0.125" or so,) and allow the screw to be preloaded properly.
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Unread 09-01-2012, 07:50 AM   #105
raypla
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Quote:
Originally Posted by mbardeen View Post
I just replaced my frameside motor mounts with brown dog mounts. Took about an hour or so to do. Passenger side is a bit tight, because of all the stuff in the way, but I was able to squeeze the old mount out and new mount in under the AC lines.

This is what my driver's side mount looked like:


Passenger's side mount was in better condition.
Yuuup here's was my DS, PS wasn't in as bad of shape.

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