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Motor mount top bolt holes stripped

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Old 03-02-2019, 03:18 PM
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Motor mount top bolt holes stripped

Hi guys,
So my top motor mount holes are stripped. One on both right and left sides of the car. No luck using m10 1.5 instead of 1.25. Any methods other than tapping?

TIA
Old 03-02-2019, 04:26 PM
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Originally Posted by Kamal El
Hi guys,
So my top motor mount holes are stripped. One on both right and left sides of the car. No luck using m10 1.5 instead of 1.25. Any methods other than tapping?

TIA
You can drill and tap larger size, use a Helicoil type insert or replace the mounts....... that's about the only 3 options

Old 03-02-2019, 06:57 PM
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Originally Posted by dannobre
You can drill and tap larger size, use a Helicoil type insert or replace the mounts....... that's about the only 3 options
Thanks thanks for the reply. Will the Helicoil type inserts stand up to the pressure of holding the motor up? I would have to stick it in the hole in the intermediate plate.
Old 03-02-2019, 07:07 PM
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Originally Posted by Kamal El
Thanks thanks for the reply. Will the Helicoil type inserts stand up to the pressure of holding the motor up? I would have to stick it in the hole in the intermediate plate.
They will hold fine.... I'm pretty sure that there is more than enough meat on the plate to secure them.

Might be a bit of fun to get at them to put them in though.

I thought you meant the top of the motor mount.... it sucks that it is the bolt that threads into the plates.
Old 03-03-2019, 01:37 AM
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Originally Posted by dannobre
They will hold fine.... I'm pretty sure that there is more than enough meat on the plate to secure them.

Might be a bit of fun to get at them to put them in though.

I thought you meant the top of the motor mount.... it sucks that it is the bolt that threads into the plates.
It's actually the holes in the plate that are stripped.
Old 03-03-2019, 06:09 PM
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just buy a new mount and new bolt
Old 03-03-2019, 06:12 PM
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Originally Posted by nycgps
just buy a new mount and new bolt
It's the holes in the cast iron plates that are stripped.

Old 03-04-2019, 09:33 AM
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Originally Posted by dannobre
It's the holes in the cast iron plates that are stripped.
which im curious to know how he managed to do that with the block already installed in the car?
Old 03-04-2019, 12:54 PM
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Originally Posted by Xero Ryuu
which im curious to know how he managed to do that with the block already installed in the car?
I installed the block
Old 03-04-2019, 12:56 PM
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Wreaking havoc on my already dying pilot bearing
Old 03-04-2019, 01:06 PM
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Originally Posted by Kamal El
I installed the block
I remember, I am just confused. Between installing the engine and finding out the holes were stripped, were you able to drive the car? How did you learn about the stripped holes? While resolving the issue check the engine and car for any other damage, hope everything is good with it
Old 03-04-2019, 02:08 PM
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Originally Posted by Xero Ryuu
I remember, I am just confused. Between installing the engine and finding out the holes were stripped, were you able to drive the car? How did you learn about the stripped holes? While resolving the issue check the engine and car for any other damage, hope everything is good with it
The the car drove fine up until the day before this original post. The passenger side hole was stript by me when I installed the motor mount because I used the wrong bolt. so I put a makeshift stud and nut in there. The driver side mount backed out by itself and when trying to put a new bolt in I found that it was stripped. I didn't know it was backed out until washing the engine bay after driving from Miami to NY and back. It started giving me **** at high rpms. Impossible to **** in high range.

So Im changing tranny oil now. Then motor mounts and pilot bearing is the plan.

engine is good so far too. I have yet to get a compression test though. Before I pay $150 for a test I'll pay $300 for a tester.
Old 03-04-2019, 05:41 PM
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Originally Posted by Kamal El
The the car drove fine up until the day before this original post. The passenger side hole was stript by me when I installed the motor mount because I used the wrong bolt. so I put a makeshift stud and nut in there. The driver side mount backed out by itself and when trying to put a new bolt in I found that it was stripped. I didn't know it was backed out until washing the engine bay after driving from Miami to NY and back. It started giving me **** at high rpms. Impossible to **** in high range.

So Im changing tranny oil now. Then motor mounts and pilot bearing is the plan.

engine is good so far too. I have yet to get a compression test though. Before I pay $150 for a test I'll pay $300 for a tester.
That sucks, but good thing you found it out before the issue got worse. Let us know how fixing it went and when you do the test. I agree, get the tester before paying for a one-time test.
Old 03-11-2019, 08:50 AM
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the motor mount bolts are m10 1.25 30mm. what size heli coils should I get? I see m10 heli coils but they are about 15mm long. Someone said to break the pin at the back of the heli coil and double them.. Is that advisable?

Do you think they can be tapped through the wheel well?

Last edited by Kamal El; 03-11-2019 at 12:54 PM. Reason: Tell me why you're perfect
Old 03-18-2019, 10:00 PM
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Old 03-19-2019, 01:12 PM
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Old 03-28-2019, 10:49 AM
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Broken bolt

So I've been dealing with this forever now. Wtf????
How do I get this out? Can i ignore it? It's dulling everything.



Old 03-28-2019, 11:14 AM
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You have to drill a hole down the center of the broken bolt... and then use an easy out to back it out. at this point it might be easier to source a used manifold...
Heat will also help... problem is you have burnished the bolt to the aluminum now and it makes things a lot more difficult
Old 03-28-2019, 11:22 AM
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Originally Posted by dannobre
You have to drill a hole down the center of the broken bolt... and then use an easy out to back it out. at this point it might be easier to source a used manifold...
Heat will also help... problem is you have burnished the bolt to the aluminum now and it makes things a lot more difficult
Yea
I forgot to do it while the engine was out. Currently using a mechanic's mac tools back out heads that are pretty sharp. Figured I'll have to do a helicoil repair anyway.

Does anyone know if this bolt can be ignored without vacuum leak on an 04 6port speed?
Old 03-28-2019, 01:18 PM
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I can't see it sealing without that bolt. I'm sure you can get a used manifold for cheap... likely way easier than trying to fix that one.

If you were local to me I have a few.....
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