Author Topic: Is it knackered?  (Read 270 times)

Offline Johnny4428

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Is it knackered?
« on: April 07, 2021, 07:32:22 PM »
Oil pump has been chewing metal particulate. Probably when bike threw drive chain and entered the casing. Despite the damage it appeared to be pumping adequately even with a missing oil restrictor.
1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3 (current project)

Offline Bryanj

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Re: Is it knackered?
« Reply #1 on: April 07, 2021, 09:12:39 PM »
I have a used one on ebay (seller r10blj) dont know whats inside but if you want it message me via ebay and we will sort it

Online K2-K6

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Re: Is it knackered?
« Reply #2 on: April 07, 2021, 09:17:19 PM »
Strange something's got through the pickup gauze significant enough to damage the rotors.  It would be through scavenge side first and into oil tank, then down the pipe for another go round pressure side too.

Clearly you can see the damge,  but it doesn't look too bad from a capacity point of view. There's a fair leeway in the system as it's technically a 30 viscosity motor when hot, but with 15w 40 oil it effectively runs over design target and protection available from relief valve so that the pump drive doesn't get over loaded.  Probably why it's not had any significant consequences.

Whether you replace or run with it cleaned up is going to depend on your outlook. Hard to quantify really, but evidence suggests it's not likely to be a problem if you carefully dress off any impact chunks with an oil stone to give best surface condition.

Offline Johnny4428

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Re: Is it knackered?
« Reply #3 on: April 07, 2021, 09:24:50 PM »
Thanks guys. I will give a good clean and check clearances and take it from there.
1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3 (current project)

Online K2-K6

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Re: Is it knackered?
« Reply #4 on: April 07, 2021, 09:39:58 PM »
Looking at the rotors again,  they're more pock marked from a bit of "clattering" as opposed to wear in terms of not much being worn away,  if that makes sense.  With the cavity volume being probably left not much different, or none at all, then that would support reasoning of very little pumping loss.

Whatever has been through there hasn't been there long, and probably just ended up left in the oil filter.

Offline Johnny4428

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Re: Is it knackered?
« Reply #5 on: April 07, 2021, 10:03:58 PM »
Looking at the rotors again,  they're more pock marked from a bit of "clattering" as opposed to wear in terms of not much being worn away,  if that makes sense.  With the cavity volume being probably left not much different, or none at all, then that would support reasoning of very little pumping loss.

Whatever has been through there hasn't been there long, and probably just ended up left in the oil filter.
Good point, thanks for the logic!
1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3 (current project)

Offline Johnny4428

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Re: Is it knackered?
« Reply #6 on: April 08, 2021, 07:51:31 PM »
Clearances coming in at >0.05 & <0.10  I would guess around 0.07mm. Well within 0.35mm specified in W/shop manual. So will clean up and re-use.


1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3 (current project)

 

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