Author Topic: 61 A10R engine disassembly  (Read 272 times)

Offline Truckedup

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61 A10R engine disassembly
« on: 21.08. 2020 20:54 »
  I disassembled the lower end today...The good is  the rod journals and timing side journal  are worn a few thousand under standard, the rod lower ends are actually round. I set the crank in the lathe and the dial indicator on the center of the crank with flywheel removed , it's within. .001. I was concerned due to the welds on the cases indicated a thrown rod or something.The welding is nice inside and out. The cam is a 357 in good shape. The left side roller bearing has a nice wear pattern, but it will be replaced
 The bad, a few broken bolts from the past...The worst was a  flywheel bolt, the  mark's on the flywheel indicated it backed out while the engine was running. This was what probably punctured the crankcase. I did remove the broken bolt without too much trouble.
  A caveman must have assembled this lump, several different types of sealer applied much too thick. Some of the RTV sealer was almost completely blocking the oil holes in the pump..
  So overall not bad...
1961 Super Rocket, 79 Triumph T140D, 96 Ducati 900M

Offline muskrat

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Re: 61 A10R engine disassembly
« Reply #1 on: 21.08. 2020 21:04 »
G'day Trucky.
Just what you'd expect after 60 years of abuse. Now to be fixed properly (in the best "hillblly" fashion). LOL
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Muskys Plunger A7

Offline Joolstacho

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Re: 61 A10R engine disassembly
« Reply #2 on: 22.08. 2020 00:39 »
It's in good hands now though by the sound of it.

Offline Slymo

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Re: 61 A10R engine disassembly
« Reply #3 on: 23.08. 2020 01:55 »
I've come to the conclusion having spend quite a few years sorting out old bikes that the quality of the mechanicing to be expected inside is in direct inverse proportion to the quantity of sealant applied to the cases and covers. I have also discovered more recently that the driest machines I have assembled involve no sealant at all where there are gaskets between faces and only the thinnest of applications between mating faces. Silicone sealant anywhere other than exaust joints is a sure sign of trouble to come.

Offline bikerboy

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Re: 61 A10R engine disassembly
« Reply #4 on: 26.09. 2020 14:31 »
I have found that if the surfaces are ok a thin smear of grease to hold the gasket in place is about all you need.

Silicone is the same as most things, if a competent person is using it then its fine if an incompetent person is using it then its a nightmare.

As for the oil pump gasket, a tiny blob of grease in the centre to hold it in place is all I ever use and I do mean a tiny bit.