1997 TJ Engine Mount Bosses Sheared Off Block

JPFUN97

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Original poster
Joined
Aug 3, 2019
Messages
11
Location
Mattoon, IL
So...the wife and I were out for a drive and noticed the fan blades slightly rubbing the shroud suddenly. Crawled underneath and noticed a NON factory engine mount bracket on the driver side. (2) of the (3) bolts had sheared off allowing the engine to drop enough for the fan to rub the shroud. I took it to a friend that has a shop to extract the broken bolts from the engine block and install new brackets and mounts. He got it apart and called with BAD news! Said the factory mount bracket hole locations in the engine block had been broken off and/or cracked. Someone had "rigged" a plate with a hole pattern to match (3) different engine block locations. These are the (2) bolt locations that had most recently sheared off. These engine block locations had also broke off and/or cracked. So...we have a 1997 TJ with 113K miles that runs great, but at this point the engine seems to be JUNK because it cannot be mounted. We've had this TJ 1-1/2 years and has been great up to this point. I'm going to start looking for a replacement engine online, but does anyone have any other ideas or suggestions? Has anyone else ever heard of this happening? Any help would be appreciated.
 
You could probably weld new mount provisions to the block I would assume.
 
That does suck. I don't think repairing it is an option. It should not be a problem finding a replacement. Northern Jeeps are parted out pretty often.
 
Just thinking "outside the box", build motor plates similar to what racers have been doing for decades in race cars.
search "sbc motor plate" this will give you the concept.
Good luck.
And welcome to the forum !
 
All 3 sheared off on my xj, I jacked it up, tacked it and buried about 15 rods of 7018 into the mount and block. Have a spare engine waiting though too..... your choice. 🤙
 
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Thanks everyone for the suggestions. I think the "sbc motor plate" version isn't going to work due to lack of room on the back side and no way to use rubber mounts to dampen the vibration into the frame. We have a local hot rod builder that has been featured nationally for his custom builds. I contacted him and described the issue and he offered to take a look to see if he can weld the mount bracket to the block...we'll see in a couple weeks when he can look at it. I will keep everyone posted. Thanks.
 
Thanks everyone for the suggestions. I think the "sbc motor plate" version isn't going to work due to lack of room on the back side and no way to use rubber mounts to dampen the vibration into the frame. We have a local hot rod builder that has been featured nationally for his custom builds. I contacted him and described the issue and he offered to take a look to see if he can weld the mount bracket to the block...we'll see in a couple weeks when he can look at it. I will keep everyone posted. Thanks.
Typically for street use motor plate extends out over the frame where you can 90 degree it to a frame stand off with rubber donut mounts. Chevy medium duty gasser trucks used a similar "front saddle mount" on the front of the big block for many years.
Hopefully the hot rodder can offer some help to you problem!
 
Cou
Thanks everyone for the suggestions. I think the "sbc motor plate" version isn't going to work due to lack of room on the back side and no way to use rubber mounts to dampen the vibration into the frame. We have a local hot rod builder that has been featured nationally for his custom builds. I contacted him and described the issue and he offered to take a look to see if he can weld the mount bracket to the block...we'll see in a couple weeks when he can look at it. I will keep everyone posted. Thanks.
Couple of things to keep in mind when trying to weld cast iron.

The #1 factor for any proper weld is access, access and access. Oh and did I mention access!
And that is really not possible in situ (love that phrase) in other word get ready to pull the engine.

Also in order to get anywhere near a semi permanent repair the area surrounding the welds should be pre-heated with a oxy/acet Rosebud torch and kept hot (edge of cherry) during the process, upon completion the area needs be very slowly cooled.

Typically cast welds fail due to the rapid localized heating and cooling causing stress fractures and failures.
 
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So...the wife and I were out for a drive and noticed the fan blades slightly rubbing the shroud suddenly. Crawled underneath and noticed a NON factory engine mount bracket on the driver side. (2) of the (3) bolts had sheared off allowing the engine to drop enough for the fan to rub the shroud. I took it to a friend that has a shop to extract the broken bolts from the engine block and install new brackets and mounts. He got it apart and called with BAD news! Said the factory mount bracket hole locations in the engine block had been broken off and/or cracked. Someone had "rigged" a plate with a hole pattern to match (3) different engine block locations. These are the (2) bolt locations that had most recently sheared off. These engine block locations had also broke off and/or cracked. So...we have a 1997 TJ with 113K miles that runs great, but at this point the engine seems to be JUNK because it cannot be mounted. We've had this TJ 1-1/2 years and has been great up to this point. I'm going to start looking for a replacement engine online, but does anyone have any other ideas or suggestions? Has anyone else ever heard of this happening? Any help would be appreciated.
Do a search on the Brown Dog website.
Brown Dog makes a larger mounting plate that uses the additional block bolt holes to mount up the factory motor mount.
The part number is S 2572.
 
Thanks everyone for the suggestions. I think the "sbc motor plate" version isn't going to work due to lack of room on the back side and no way to use rubber mounts to dampen the vibration into the frame. We have a local hot rod builder that has been featured nationally for his custom builds. I contacted him and described the issue and he offered to take a look to see if he can weld the mount bracket to the block...we'll see in a couple weeks when he can look at it. I will keep everyone posted. Thanks.
Good plan, let us know.