Hi guys,

Is it possible that a worn primary gear bush could cause an engine vibration over about 3000 rpm and a lowering of oil pressure. Cause I have these symptoms and have found bronze coloured shavings in the sump, lots of them!

Thanks in advance.

Richard.

You really wouldn't see Primary Gear Bush material in the sump. Sorry to say it sounds more like Crank Bearings, Mains and / or Thrust and / or Big Ends.

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bronze (brass) shavings could also be coming from the diff spider gear washers....

engine out!

You do mean copper, Simon, you are close.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

probably center main brg (at least)

maybe cracked crank too

rip it out & apart

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

missed it by *that much*

Yeah it is actually bronze or copper chips in the sump, engine out again I guess at least its nice and cool this weekend.

UPDATE....

Well the engine is out and I found a couple of problems, 1) the diff is loose as s*it, and the main bearing has spun. Looks like the copper chips were from the thrust bearings on the mains.

Thats as far as i've got to date. I will have to ponder this for a few days

Pardon the french, but Oh crap. Sorry to learn of this.

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Thanks mate, I just hope the crank aint too bad

Fair enough, but I'd be really really worried about the block (and cap). Will probably need facing and then line boring to put it right. If the Crank is an EN40B and still has Nitriding it has a good chance of being OK, but in any event, most likely nothing that a straight forward grind won't fix.

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I'll just have to see when I pull the crank out, the cap looks ok though, cross fingers.

Check the crank's endfloat when you reassemble it. The factory spec of .003" is NOT enough if you are going to rev it. I found out the hard way... it starves the centre main of oil flow, then the shells spin.

You want .006" endfloat at least on a revvy 1275. Because the crankwebs flex.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

sh*tballs!

did you do anything to cause it, or did it just happen?

Well yeah I suppose too many revs, I noticed an engine vibration on the way home from a club sprint in tamworth.

http://www.youtube.com/tech160s#p/a/u/0/3PVASc6GKqc