Rod cap bearing orientation

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wattsmonkey
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Rod cap bearing orientation

Post by wattsmonkey »

Hi chaps,

I'm getting conflicting information on the orientation of the rodcaps.

The B34 bottom end had the tangs aligned - confirmed with witness marks on the rods themselves.

I've just pulled a piston on the M90 to see about having new rings made and the tangs are at opposing ends - please see pic if this isn't clear.

Could someone confirm the correct orientation, please??

Many thanks,

Rob
M90 bearing cap.jpg
M90 bearing cap.jpg (74.44 KiB) Viewed 137 times
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tschultz
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Re: Rod cap bearing orientation

Post by tschultz »

Note that Mark is the tangs marking from the opposite end.

The tangs sit on opposite sides when installed together, leaving imprints on the opposite faces.

Each bearing should have the tangs sitting in the groove and they should each be opposite each other when installed.
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wattsmonkey
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Re: Rod cap bearing orientation

Post by wattsmonkey »

Thanks Tom,

That’s really reassuring. I don’t think this m90 has been apart, so that makes perfect sense.

Nice to know this engine is correct - the other spare b34 with the wrong orientation is also the one with oversize pistons and standard rings- I don’t think it was the best reconditioning ever seen, especially with the B35 head fitted.

Lesson learned (ish): it cost me £1400, but that included a hartge valve cover and what I very much hope is a shrick cam.
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
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