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Broken Motor Mount

Snapped one of the prothane motor mounts, not sure how. Found two pieces of it inside the K-frame. The guys at LMR said they have not heard of this happening before with these mounts and they were quick to contact the company that makes them for a replacement.

mount1_zpsfd06acd0.jpg
 
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97
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HPDE
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10-20 Years
Texas
Just a thought...did the more rigid motor mounts help with the shifting problem our cars have? Mainly getting it into 5th gear at speed which I believe is the result of a few different factors but one of them being the movement of the engine and tranny when torque is applied.
 

Justin

Save the dawn for your dishes!!!
Flyboygsxr said:
Just a thought...did the more rigid motor mounts help with the shifting problem our cars have? Mainly getting it into 5th gear at speed which I believe is the result of a few different factors but one of them being the movement of the engine and tranny when torque is applied.
for me the shifts became much more solid. I have done any WOT shifts from 4th to 5th at redline though. but it did make a noticeable difference
 
Passenger side. It will be interesting to see what happened when I get it out. I (with help) did manage to get the aluminum piece out of the K-frame but the prothane part is still stuck in there.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
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Time Attack
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NY Metro
I am right that the engine rotates clockwise when looking from the front and it torques over towards the passenger side? This would cause the drivers side mount to be in tension and the passenger side in compression under load. If your passenger side pulled through the only thing I can think of is the mounting bolt was over tightened causing the aluminum nutsert to fail and pull through the mount. Who did the install?
If I have it all wrong let me know sometimes I get dyslexic about these things.
Steve
 
A buddy of mine had the top bolt loosen up out of his.....can't remember which side. My tech cranked mine down and loctited the hell out of them after we pointed that out to him so hopefully they're not overtorqued???? I paint marked both of mine and have been keeping an eye on them.
 
steveespo said:
I am right that the engine rotates clockwise when looking from the front and it torques over towards the passenger side? This would cause the drivers side mount to be in tension and the passenger side in compression under load.

These were torqued to specs, I know the guy that installed them ;)
 
I could be wrong here, but it is possible that the lower bolt came loose and fell out? The reason I ask is that it is hard to see any damage besides missing parts in the picture. The lower side bolt on my driver side mount fell out and looked just like this. Luckily the k member "caught" the bushing and metal washer that I was able to fish out and reuse.

Did he torque the mounts from the top and the bottom? I tightened the bottom bolts by hand and then torqued the top bolt. The bolt fell out a week later. When I torqued the mount the second time (with loctite) I placed a wrench on the bottom bolt and torqued the top bolt. The wrench on the bottom rotated into the subframe and allowed me to torque both bolts without actually putting a torque wrench on the bottom bolt.

Flyboygsxr said:
Just a thought...did the more rigid motor mounts help with the shifting problem our cars have? Mainly getting it into 5th gear at speed which I believe is the result of a few different factors but one of them being the movement of the engine and tranny when torque is applied.
The engine mounts help me find the gears better because they are moving around a lot less. The gear engagement didn't change at all. Fifth gear still doesn't like to be rushed, especially above ~110.
 

Grant 302

basic and well known psychic
^Glad I'm reading about some of these issues...

YellowBoss said:
Maybe but is the tension in the passenger side mount compressing when you are spinning counter-clockwise on a left hand turn track in the grass and on pavement? Or would you have to spin clockwise on a right hand turn track? ;D

If I think too hard about it, the resultant forces would be in the pitch/dive axis. ;)
 
loco pantelonez said:
I could be wrong here, but it is possible that the lower bolt came loose and fell out? The reason I ask is that it is hard to see any damage besides missing parts in the picture. The lower side bolt on my driver side mount fell out and looked just like this. Luckily the k member "caught" the bushing and metal washer that I was able to fish out and reuse.

Most likely this is what happened, so broken or snapped were not good terms to use. I did only torque the bolt from the top when I installed them. I will make sure we do both when installing the new one and check the drivers side also. At least I'm not the onlt person this happened to.
 

Grant 302

basic and well known psychic
ArizonaGT said:
I think I will wait to do this mod until more conclusive evidence and track use exists...

I was just waiting to look and measure how much clearance I'd lose at the oil pan...now I'm going to wait for more feedback too.
 
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Mhhhh, I just bought the HD engine mounts from Steeda and I will make sure to loctite it additionally to properly torqueing the bolts. Will post here in case I have a similar incident, which I dont hope.
 

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