Cracked rear left motor mount hole

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kngkong
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Cracked rear left motor mount hole

#1

Post by kngkong » Mon Jan 21, 2019 1:26 am

Discovered this last night. Would anyone in their right mind ever consider repairing this without completely dismantling the cases? Looks the washer is distorted and creating outward pressure on the hole. Unless that seat was never spot faced well but I think I would have noticed that when assembling. I figure I have to start by taking that bolt out to have a peak and then most likely taking this motor out and having the case repaired. Less than a hundred miles on it.

Any chance this could be repaired by just taking off the barrels or something?

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Buddhahoodvatoloco
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Re: Cracked rear left motor mount hole

#2

Post by Buddhahoodvatoloco » Mon Jan 21, 2019 1:54 am

No sweat, with some pre-planning might be able to be done where it's at.
I have used this stuff with solid results, but to each his own.
https://www.aluminumrepair.com/

kngkong
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Re: Cracked rear left motor mount hole

#3

Post by kngkong » Mon Jan 21, 2019 3:05 am

Not sure if serious.

Buddhahoodvatoloco
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Re: Cracked rear left motor mount hole

#4

Post by Buddhahoodvatoloco » Mon Jan 21, 2019 4:37 am

Oh I am, fixed a couple rear motor mount cracks/splits wit that stuff.
Preparation, then dial in the washer relief.
Or,,,,,,,,,,, :idea:

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Re: Cracked rear left motor mount hole

#5

Post by kngkong » Mon Jan 21, 2019 5:54 am

Cool. Well hopefully I’ve caught it early enough to minimise the damage. I guess it will come down to how much I need to cut out to get past the cracks. I don’t know how that washer distorted like that.

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Re: Cracked rear left motor mount hole

#6

Post by Buddhahoodvatoloco » Mon Jan 21, 2019 3:16 pm

slowly at first removing material, or grove it.
Why it cracked/split, anybodies guess. Old motor.

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Re: Cracked rear left motor mount hole

#7

Post by kngkong » Tue Jan 22, 2019 8:20 pm

I took the bolt out the othernight. The area under the washer was not faced properly and was dished.

If it is possible to TIG this without disassembling the engine does anyone have any ideas on how to face that washer relief with the barrels in place? I might be able to fit in there with a 90 degree head on the bridgeport?

Does anyone use heavier washers to reduce the chance of this happening?

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Re: Cracked rear left motor mount hole

#8

Post by Buddhahoodvatoloco » Tue Jan 22, 2019 8:44 pm

wow, puppies cracked all the way through, different story :cry:

1950Panhead
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Re: Cracked rear left motor mount hole

#9

Post by 1950Panhead » Wed Jan 23, 2019 2:44 am

If it is possible to TIG this without disassembling the engine does anyone have any ideas on how to face that washer relief with the barrels in place? I might be able to fit in there with a 90 degree head on the bridgeport?
It is possible to remove left case, I have done this, remove case bolts, lay engine flat, remove cylinder base nuts, slide cylinders up 1"
Drill .125" holes up crack line, open slot with chainsaw file, then weld shut, weld top and machine flat.

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Re: Cracked rear left motor mount hole

#10

Post by 1950Panhead » Wed Jan 23, 2019 2:48 am

Image

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Re: Cracked rear left motor mount hole

#11

Post by kngkong » Wed Jan 23, 2019 8:07 pm

Wow, cool. That saves a little work. :D

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Re: Cracked rear left motor mount hole

#12

Post by ron66 » Sat Jan 26, 2019 10:56 am

Hi, I always check with a feeler gauge if the engine sits nice and even in the frame and, if necessary, shim before tighten it. I don't know why your case broke. Usually the front mounts are prone to brake, if there's a gap underneath. However, shimming takes a lot of stress out of the mounts.

Greets
Ron

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Re: Cracked rear left motor mount hole

#13

Post by Buddhahoodvatoloco » Thu Jan 31, 2019 3:14 am

Beer cans, soda cans work marvelous as shims. :lol: :wink:
ron66 wrote:
Sat Jan 26, 2019 10:56 am
Hi, I always check with a feeler gauge if the engine sits nice and even in the frame and, if necessary, shim before tighten it. I don't know why your case broke. Usually the front mounts are prone to brake, if there's a gap underneath. However, shimming takes a lot of stress out of the mounts.

Greets
Ron

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