BMC 5.1 mains and big ends

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GaryParnell
Posts: 3
Joined: Wed Apr 04, 2018 7:10 am

BMC 5.1 mains and big ends

Post by GaryParnell » Mon Jul 23, 2018 2:38 pm

Hello I’m looking for a set of 0.045” mains and big end for my BMC 5.1 try a few places and can’t get them. 0.040” and 0.050 available.
Many thanks
Gary



ploughman
Posts: 101
Joined: Sun Apr 01, 2018 6:21 pm

Re: BMC 5.1 mains and big ends

Post by ploughman » Tue Jul 24, 2018 11:53 am

Hello.
Very odd size that, how have you arrived at it? IE, stamped on shells or measurement, if the latter, I suspect a worn 040 regrind.
regards,
Harry

GaryParnell
Posts: 3
Joined: Wed Apr 04, 2018 7:10 am

Re: BMC 5.1 mains and big ends

Post by GaryParnell » Tue Jul 24, 2018 12:04 pm

Hello that’s the size stamped on the back of the shells (genuine bmc parts) Have had the crank check and all ok, might have to have it ground to 0.050”.
Regards
Gary

ploughman
Posts: 101
Joined: Sun Apr 01, 2018 6:21 pm

Re: BMC 5.1 mains and big ends

Post by ploughman » Tue Jul 24, 2018 4:53 pm

Hi,
Is it a gold seal unit? If so that could explain it, BMC would have the buying power to make odd size bearings economical.

diggerdeano
Senior Member
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Joined: Sat Mar 31, 2018 9:04 am
Great Britain

Re: BMC 5.1 mains and big ends

Post by diggerdeano » Tue Jul 24, 2018 6:29 pm

hi try charnleys they will most likely have them on the shelf .

GaryParnell
Posts: 3
Joined: Wed Apr 04, 2018 7:10 am

Re: BMC 5.1 mains and big ends

Post by GaryParnell » Wed Jul 25, 2018 9:09 am

Yes it is a gold seal engine and Charley’s are useless try many times over a good year and not got anywhere

ploughman
Posts: 101
Joined: Sun Apr 01, 2018 6:21 pm

Re: BMC 5.1 mains and big ends

Post by ploughman » Wed Jul 25, 2018 10:22 am

Hi Gary,
think that clears up the mystery, and adds cost to your restoration. Sadly, your not alone with your problems with Charnleys, a friend with a pre 1953 Perkins engined nuff, has similar, wrong parts when delivered, can never talk to anyone, its always "we will ring you back" which never happens.
Must say that though I have been working with engines for many years, I have never come across such odd size bearings. Fordson were close, but you hand fitted them, and the oversize bores were in Fractions 1/16th,1/8th,etc.
Regards,
Harry

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Jamie Davis
Site Admin
Posts: 175
Joined: Fri Mar 30, 2018 6:53 pm
Great Britain

Re: BMC 5.1 mains and big ends

Post by Jamie Davis » Wed Jul 25, 2018 11:01 am

I am compiling a list of parts suppliers. I'm sure some others will be able to help.

https://nuffieldtractor.com/viewtopic.php?f=24&t=984
Jamie Davis

Past - Nuffield 10/60
Present - Nuffield 460 & Nuffield 4/65

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