Author Topic: T140v '76 tech help please  (Read 3719 times)

Andy_G

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T140v '76 tech help please
« on: December 31, 2006, 08:54:21 PM »
Hi all, I am rebuilding my Bonnie engine and would like to know if 1976 models have a crank shaft oil seal on the primary drive side. I notice in the Haynes manual that the pre '75 models do. Does it make a difference which way the inner part of the roller bearing fits to the crankshaft?
Also, I tightened the con rod nuts to 28 ft/lbs and then realised that post '75 models should be torqued to 22 ft/lbs. Can I slacken and re tighten or will I need to replace them? (They were new anyway but I guess they may have stretched now).  :-/

Offline L.A.B.

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Re: T140v '76 tech help please
« Reply #1 on: December 31, 2006, 10:15:43 PM »
Quote
Hi all, I am rebuilding my Bonnie engine and would like to know if 1976 models have a crank shaft oil seal on the primary drive side. I notice in the Haynes manual that the pre '75 models do.

No T140 should have a crank seal on the primary side as this was deleted for the 1971 production year twin models (T120 Bonneville etc.).  


Quote
Does it make a difference which way the inner part of the roller bearing fits to the crankshaft?

Normally you would fit the parts the same way that they came out of the box (if you are fitting new parts) generally with the bearing markings on both parts fitted on the same side.

Quote
Also, I tightened the con rod nuts to 28 ft/lbs and then realised that post '75 models should be torqued to 22 ft/lbs. Can I slacken and re tighten or will I need to replace them? (They were new anyway but I guess they may have stretched now).

You need to replace them as they are stretch bolts.
And I suggest you get hold of a copy of the 1976 factory manual as the Haynes type tries to cover too many models in the same book which can frequently be misleading or sometimes gives incorrect information for a particular model year.
« Last Edit: December 31, 2006, 10:16:19 PM by L.A.B. »
L.A.B.

Andy_G

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Re: T140v '76 tech help please
« Reply #2 on: January 01, 2007, 04:25:49 PM »
Thanks for your help, I will order (another) set of big end bolts/nuts and start again. I'm sure I'll have a few more queries before I have finished but I'll be much wiser for the experience. Happy New Year

Offline guinnless

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Re: T140v '76 tech help please
« Reply #3 on: January 18, 2007, 07:36:55 AM »
I have to agree with L.A.B. try to get the genuine workshop manual - they are cheaper than the Haynes book of lies and far more accurate. If you put the pages into plastic wallets(they come in a ring binder) they also last far longer than the books do because you can wipe the oil off! The haynes books are usefull for the photos sometimes. Britbits in Christchurch sold me mine many years ago-no doubt they cost more now but mine is twenty years old and still readable

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