Front bearing cover mishap

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100RT79
Posts: 5
Joined: Thu Apr 13, 2023 2:35 am

Front bearing cover mishap

Post by 100RT79 »

Hi All,
I'm tearing down a 79 R100RT but made a pretty big mistake yesterday. As I was removing the (original) front bearing from the bearing cover, I forgot to remove the pin. Needless to say it sheared off and left a bit of a mess.

Do you think I need to replace the bearing cover or will this be ok once I put the new bearing (and pin) into the cover? Its only a small scratch but its pretty deep as you can see (pics attached). I will of course make sure the thrust washer surface is smooth.

My thinking is once the bearing is in, this is a pretty tight seal an there is oil both sides of the cover so any small leakage wouldn't be an issue?

Thanks in advance
Attachments
Bearing.png
Bearing.png (1.32 MiB) Viewed 1133 times
100RT79
Posts: 5
Joined: Thu Apr 13, 2023 2:35 am

Re: Front bearing cover mishap

Post by 100RT79 »

Oh and that black line isn't a crack, its a hair ;o)
Rob Frankham
Posts: 1214
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: Front bearing cover mishap

Post by Rob Frankham »

I think it will probably be OK... not ideal but OK... as long as the casting isn't distorted and oil under pressure can't escape from the central well of the bearing seat. Not really sure how you could be certain of the latter though.

Rob

Edit...

OK, I'm having second thoughts now... not quite sure that the damage won't allow oil to escape due to the feed to the rockers. I'll have a lookok at a bearing and casting and come back.

Rob
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100RT79
Posts: 5
Joined: Thu Apr 13, 2023 2:35 am

Re: Front bearing cover mishap

Post by 100RT79 »

Thanks Rob, I appreciate the help.
Attached are a few more images.
There’s a few second hand available on eBay, if I got a replacement would there be any figment issues onto the block?
Attachments
FAC6E006-4452-46A8-ABDE-F11535F407F1.jpeg
FAC6E006-4452-46A8-ABDE-F11535F407F1.jpeg (327 KiB) Viewed 1114 times
57826CD2-D46C-467D-B41C-5D004EF013AA.jpeg
57826CD2-D46C-467D-B41C-5D004EF013AA.jpeg (359.03 KiB) Viewed 1114 times
22D4FBEB-C669-4E85-B934-2C7399776676.jpeg
22D4FBEB-C669-4E85-B934-2C7399776676.jpeg (898.3 KiB) Viewed 1114 times
100RT79
Posts: 5
Joined: Thu Apr 13, 2023 2:35 am

Re: Front bearing cover mishap

Post by 100RT79 »

Fitment not figment ;o)
Rob Frankham
Posts: 1214
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: Front bearing cover mishap

Post by Rob Frankham »

OK,

I think you'll be alright.

I wanted to check the the oil to the rocker feeds. metred by the ground flat in the crankshaft front main journal, wouldn't tend to escape via the chipped casting. I have looked at a front bearing support casting and confirmed that the rocker feed galleries are on the other side of the bearing so I would be fairly confident there will be little or no oil pressure loss... provided, as I said, that the casting isn't otherwise damaged or distorted in that area.

Rob
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100RT79
Posts: 5
Joined: Thu Apr 13, 2023 2:35 am

Re: Front bearing cover mishap

Post by 100RT79 »

Great thanks Rob. Really appreciate your help.
I don’t think anything else is damaged, it was heated and pulled.
Stupid mistake, I knew it was there and just forgot.
PAS
Posts: 163
Joined: Sun Apr 06, 2014 10:52 am

Re: Front bearing cover mishap

Post by PAS »

I wonder if some JB Weld carefully applied and shaped would work?
Rob Frankham
Posts: 1214
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: Front bearing cover mishap

Post by Rob Frankham »

PAS wrote: Fri Apr 14, 2023 1:44 pm I wonder if some JB Weld carefully applied and shaped would work?
I think you have to balance 'fixing' a fault that shouldn't cause a problem agains the possibility of the JB weld working loose and getting into the engine. Personally I wouldn't.

Rob
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