Author Topic: Post big bang - Whitsend A10  (Read 3837 times)

Offline charles whitfield

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Re: Post big bang - Whitsend A10
« Reply #60 on: 28.06. 2014 14:41 »
3 angle? presumably that needs a machine shop
I was thinking of just regrinding them in myself in the traditional way, but more than happy to try it
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Charles

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Re: Post big bang - Whitsend A10
« Reply #61 on: 28.06. 2014 15:59 »
Inlet runs red hot so it will be blue if not black.

I think the exhaust valve is the hot one.

Offline BSA_54A10

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Re: Post big bang - Whitsend A10
« Reply #62 on: 29.06. 2014 14:37 »
Inlet runs red hot so it will be blue if not black.

I think the exhaust valve is the hot one.

OOps, then again it was a really good shiraz
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Offline charles whitfield

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Re: Post big bang - Whitsend A10
« Reply #63 on: 29.06. 2014 17:19 »
Should I put more spirit in the inlet valve!

Offline charles whitfield

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Re: Post big bang - Whitsend A10
« Reply #64 on: 30.06. 2014 19:15 »
Thanks everyone - found the root of the problem I think
I stripped the piston from the undamaged conrod - the top conrod oil feed hole is not in line with the hole in the bush - it looks like it has turned, but not sure why?
Would it be fair to assume the same had happened on the broken side, causing the bush to fail? etc, etc
When I bought the new NOS conrods, the seller immediately said it sounded like it had not been line reamed and that was the cause
Opinions welcomed
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Charles

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Re: Post big bang - Whitsend A10
« Reply #65 on: 30.06. 2014 20:35 »
That could be one reason. A good inspection of the bore and pistons should tell. Is there marking other than fore and aft? Another cause could be pinging hammering the L/E bush loose. Or the PO has replaced the L/E bush's and done a bad job of it. A lot of books say to push the old bush out with the new one going in. Don't *ex*. Heat the rod, press old bush out, freeze the new bush and it should drop in or only need a little shove. ALWAYS check for square and true before use.
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