Oil valve solution to oil falling to crankcase

It's worth checking that the side plates are not protruding past the mating surface of the pump, (that issue has been seen on here before).

Maybe the oil pump is a good canditate for one of @jseng1 reinforced silicone gaskets?
 
cliffa said:
It's worth checking that the side plates are not protruding past the mating surface of the pump, (that issue has been seen on here before).

Maybe the oil pump is a good canditate for one of @jseng1 reinforced silicone gaskets?
Click to expand...
Shipping from US is a killer - even for gaskets.
A friend ordered some from Jim recently - $46US shipping, and apparently that's the "slow boat". An extra (wait for it) $50US for express/tracked.
Just for a few gaskets.
I like his stuff but...
Cheers
 
cliffa said:
It's worth checking that the side plates are not protruding past the mating surface of the pump, (that issue has been seen on here before).

Maybe the oil pump is a good canditate for one of @jseng1 reinforced silicone gaskets?
Click to expand...
Thanks - Did check the side plates - no problem there.
I've seen that before too 👍
Cheers
 
I know this is a slight derailment, but has anybody tried substituting a ball bearing in place of the plunger on a MkIII ? it seems to me one may seat better on the seal, as it would allow for any (god forbid) manufacturing discrepancies / misalignments.
 
cliffa said:
I know this is a slight derailment, but has anybody tried substituting a ball bearing in place of the plunger on a MkIII ? it seems to me one may seat better on the seal, as it would allow for any (god forbid) manufacturing discrepancies / misalignments.
Click to expand...
It's possible a ball bearing could work better
I suppose the seal may not be completely flat so the piston can't make a complete seal
Where as a ball would align itself
Would you propose just a spring and ball?
Or a modified piston?
I have a MK3 timing cover on my 750 it's pretty good for a few weeks standing maybe more
I can't tell you exactly how long because the bike is in use
I never drain the sump the electric start always starts it and I have a reed valve in the timing case so there shouldn't be too much pressure to blow the primary side main bearing oil seal out
 
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baz said:
It's possible a ball bearing could work better
I suppose the seal may not be completely flat so the piston can't make a complete seal
Where as a ball would align itself
Would you propose a just a spring and ball?
Or a modified piston?
I have a MK3 timing cover on my 750 it's pretty good for a few weeks
I can't tell you exactly how long because the bike is in use
Click to expand...
They were my thoughts too baz. Just wondering if anyone had tried it. I guess a right sized ball would be quite heavy though, so maybe a piston with a cone shape nib on the end would be the answer?
 
Okay - now a slightly different twist...
After fitting the thicker gasket with sealant on it the sumping slowed significantly but did not stop.
After a week or so I (again!) pulled the timing cover, with full oil tank, and sealed the pump outlet (cling wrap & o-ring) cleaned and dried the area around the pump and watched.
To my surprise oil was seeping (slowly) from the upper joint between the pump body and the brass/bronze end plate. When I removed the pump I was able to tighten the screws by 15 to 30 degrees. Three of the screws are now 30 to 45 degrees beyond the original AN punch marks.
Obviously the screws had to be removed by AMR to machine & fit o-rings but they advise the pump was tightened using loctite red.
If that joint is seeping under gravitational pressure I imagine the rate will be substantially higher under operating pressure - and that side is the high pressure feed to the engine.

My question to forum members is has anyone had leaks like this and, if so, how did you solve it? It is obviously a tricky area to attempt to use sealant of any kind.
Maybe just tightening and locking the screws is sufficient but I'm a little tired of work inside the timing cover.
Cheers
 
robs ss said:
Okay
Maybe just tightening and locking the screws is sufficient but I'm a little tired of work inside the timing cover.
Cheers
Click to expand...
I'm about to find out...as I'll do what you did and test it with the cover off...with a blank oil pump gasket with the outlet blocked on the new AN pump 💪😎👍
 
KiwiShane said:
I'm about to find out...as I'll do what you did and test it with the cover off...with a blank oil pump gasket with the outlet blocked on the new AN pump 💪😎👍
Click to expand...
No Shane - to test the pump you need to block the pump outlet but fit a standard gasket, so that oil gets in there.
My "blank gasket" test was just to check there was not some "other" oil route to the sump - crack or porosity (shudder)
Cheers
 
robs ss said:
No Shane - to test the pump you need to block the pump outlet but fit a standard gasket, so that oil gets in there.
My "blank gasket" test was just to check there was not some "other" oil route to the sump - crack or porosity (shudder)
Cheers
Click to expand...
Yes I've got a old gasket or will reuse the current one and blank the outlet of the pump off.....I may do both tests
 
Rob I’m wondering if that leaky plate is as bad as you seem to think.

Like electrickery, fluid takes the path of least resistance, as the pump is normally pumping oil into open ended cavities, and running at a relatively low pressure, I would imagine that almost of the oil is gonna go where it’s supposed to.

And a small ’seep’ would surely take a LONG time to be the cause of significant wet sumping.

Its still a good find, and worth fixing, I just doubt it’s the route cause of very much.
 
Fast Eddie said:
Rob I’m wondering if that leaky plate is as bad as you seem to think.

Like electrickery, fluid takes the path of least resistance, as the pump is normally pumping oil into open ended cavities, and running at a relatively low pressure, I would imagine that almost of the oil is gonna go where it’s supposed to.

And a small ’seep’ would surely take a LONG time to be the cause of significant wet sumping.

Its still a good find, and worth fixing, I just doubt it’s the route cause of very much.
Click to expand...
Maybe - as I said the rate of leakage will increase with increase pressure - so I will fix it anyway.
Cheers
 
New pump on... oil in ...out let blocked....[edit] bottom of case still dry [edit] pump body dry as expected...so will drain oil tonight and button it all up..
The new pump works as a new one should (tighter)...will have original pump machined/resurfaced to except seals and modify cover for a later date...
 

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I fitted a mk3 cover a few days ago and noticed one thing , when you take out the pump outlet bush , and press in the new style, I don't think the actual face of the pump spot face is big enough for the bigger later model spigot , so if you over press it , it could go crook-ed and distort it . So it could cause a slow bleed .
 
Shelby-Right said:
I fitted a mk3 cover a few days ago and noticed one thing , when you take out the pump outlet bush , and press in the new style, I don't think the actual face of the pump spot face is big enough for the bigger later model spigot , so if you over press it , it could go crook-ed and distort it . So it could cause a slow bleed .
Click to expand...
Did you get the T cover from Tim ?
Is yours bleeding?
 
KiwiShane said:
Did you get the T cover from Tim ?
Is yours bleeding?
Click to expand...
Yep , not sure yet , I went for a 30 mile ride today , but I over filled a little , but looking good, oil pressure went to 90 dead cold , but came back ok , relief is working , I just organized a gauge and will get that mounted and plumbed soon .
 
Shelby-Right said:
I fitted a mk3 cover a few days ago and noticed one thing , when you take out the pump outlet bush , and press in the new style, I don't think the actual face of the pump spot face is big enough for the bigger later model spigot , so if you over press it , it could go crook-ed and distort it . So it could cause a slow bleed .
Click to expand...
Many years ago I fitted a MK3 cover to my 750
I don't remember changing the output dowel on the oil pump
I did fit the flat type seal
No problems over 20 years ago now
I've never had an oil pressure guage on my bike but the pender oil pressure light goes out immediately the engine fires
And stays out 2 or 3 seconds after it's stopped
 
baz said:
Many years ago I fitted a MK3 cover to my 750
I don't remember changing the output dowel on the oil pump
I did fit the flat type seal
No problems over 20 years ago now
I've never had an oil pressure guage on my bike but the pender oil pressure light goes out immediately the engine fires
And stays out 2 or 3 seconds after it's stopped
Click to expand...
Still not a bad idea to put a master gauge on at the port by the oprv , just to see what it's got , then remove , and recheck hot .
 
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