oil pump scavenge pressure?

I need a check valve to prevent wet sumpping from the exit side
of oil pump, not inlet.
About what pop off to flow pressure should I seek in a check valve?

hobot

Oh boy, here we go.

This should be fun, I'll bring the Popcorn.

I bought a anti-wet sumping valve but I'm not going to use it, I'm going to do the AMR deal.

Unclviny

hobot said:

I need a check valve to prevent wet sumpping from the exit side
of oil pump, not inlet.
About what pop off to flow pressure should I seek in a check valve?

hobot

Click to expand...

Well since it is a positive displacement pump it should produce several hundred pounds of pressure before it breaks the shaft. I would figure any old inlet side anti-wetsump valve would do just fine. But why not just run the return line into the tank above the oil level? Jim

A hot motor idling can drop to just a few pounds of pressure. Any restriction in the output side of the pump would cause me great angst.

hobot said:

I need a check valve to prevent wet sumpping from the exit side
of oil pump, not inlet.

Click to expand...

No oil should be able to flow back to the pump-except for a certain amount of that oil which was in left the return pipe when the engine stopped? Even the spin-on filter is below the level of the pump, so its contents wouldn't count.

hobot said:

About what pop off to flow pressure should I seek in a check valve?

Click to expand...

Theoretically, there should be practically no pressure in the scavenge side at all-as the oil does not have to pass through any major restriction-such as plain bearings. The only restriction would come from the spin-on oil filter (if fitted?) which would be negligible, and also the oil has to be pumped "uphill" to return it to the oil tank and again, I dubt that would be capable of generating much pressure within the scavenge system?

L.A.B said:

No oil should be able to flow back to the pump-except for a certain amount of that oil which was in left the return pipe when the engine stopped? Even the spin-on filter is below the level of the pump, so its contents wouldn't count.

Click to expand...

I am guessing Hobot has a custom oil tank without a stand tube. Jim

comnoz said:

I am guessing Hobot has a custom oil tank without a stand tube. Jim

Click to expand...

That might be bad, the return could/would aerate the oil, that's perhaps why there's a stand tube.

Cash

BSA use a ball bearing with no spring in a vertical alloy tube in the oil return, as soon as the pump turns the ball is pulled upwards against a horizontal wire, when the engine stops gravity takes over and the column of oil forces the ball against the alloy seat.

Opps, know all i ever want or need to on factory Commandos so
only question I have here are always about Ms Peel's deal, nothing
normal Norton applies. Here's the plumbing physic review
in a case that the excrement must indeed flow up hill.
post65677.html?hilit=plumbing%20physics#p65677

Oil in spine tube has more head than oil in a tank and w/o a check
valve near point of frame tank entry, there's nothing to stop back
flow via pump into sump.

I thought Jim had solved issue by the great scavenge pressure pump can
develop, my relief immediately shot down by Mylar reminding
me about low idle pressure flow drop to a trickle.
Yet hm so what?

Oil will still flow to inlet and supply crank by sling under low
loads and eventually scavenge side should have enough wet sump
to shove oil to open a check valve against reasonable spring.
Yet hm am I missing an oiling circulation issue here?

Alas there are at least 5 types and many version of check valves,
flappers, butterfly, balls, diaphragms with and w/o springs, some do and some
don't need gravity to work. I get in weird attitudes for good intervals
so don't want to depend on gravity types.

Not sure if Norton anti-sump valves, designed to barely
resist flow in one direction, would really seal with Peel's
extra height of oil. Beside the a/s valves I've seen advertised
have hose barbs and Jubilee-hose clamps are a taboo item
on Peel.

So Mylar input implies I need a low PSI opener and will return
the hard to open fuel version [$69] and get one i found last pm
for $50 that opens with less than a pound. I call the vendors
to see what they suggest, now I know what to thing about it.

Removed what's seen below including the quart of oil and
battery tray, replaced by what left laid on tank. Not shown
is un-needed stash pipe barrel for pre-filter off inlet valve.


What left when installed, minus the plumbing to get oil to filter
then into frame, all behind the cradle but above swing arm.


Maybe this place has what i need.
http://www.andair.co.uk/system/index.html

hobot

hobot said:

Opps, know all i ever want or need to on factory Commandos so
only question I have here are always about Ms Peel's deal, nothing
normal Norton applies. Here's the plumbing physic review
in a case that the excrement must indeed flow up hill.
post65677.html?hilit=plumbing%20physics#p65677

Oil in spine tube has more head than oil in a tank and w/o a check
valve near point of frame tank entry, there's nothing to stop back
flow via pump into sump.

I thought Jim had solved issue by the great scavenge pressure pump can
develop, my relief immediately shot down by Mylar reminding
me about low idle pressure flow drop to a trickle.
Yet hm so what?

Oil will still flow to inlet and supply crank by sling under low
loads and eventually scavenge side should have enough wet sump
to shove oil to open a check valve against reasonable spring.
Yet hm am I missing an oiling circulation issue here?

Alas there are at least 5 types and many version of check valves,
flappers, butterfly, balls, diaphragms with and w/o springs, some do and some
don't need gravity to work. I get in weird attitudes for good intervals
so don't want to depend on gravity types.

Not sure if Norton anti-sump valves, designed to barely
resist flow in one direction, would really seal with Peel's
extra height of oil. Beside the a/s valves I've seen advertised
have hose barbs and Jubilee-hose clamps are a taboo item
on Peel.

So Mylar input implies I need a low PSI opener and will return
the hard to open fuel version [$69] and get one i found last pm
for $50 that opens with less than a pound. I call the vendors
to see what they suggest, now I know what to thing about it.

Removed what's seen below including the quart of oil and
battery tray, replaced by what left laid on tank. Not shown
is un-needed stash pipe barrel for pre-filter off inlet valve.

What left when installed, minus the plumbing to get oil to filter
then into frame, all behind the cradle but above swing arm.

Maybe this place has what i need.
http://www.andair.co.uk/system/index.html

hobot

Click to expand...

Can someone translate this into English for me, its doing my head in.

Rich_j said:

Can someone translate this into English for me, its doing my head in.

Click to expand...

You are kidding; right?

I think hobot could be the Arkansas equivalent of Stanley Unwin?

[video]http://www.youtube.com/watch?v=R2nI_3VBEtA[/video]

[Translation to structured English grammar, concerning OIF hobot style]

hobot has had decade+ of dramatic Commando learning curves -
factory to special modifications and their many modes of failures,
so will not be pestering list with novice issues, only new
issues surrounding Ms Peel's unknowns and work a rounds.

Need check valve where oil leaving filter enters LH rear frame tube.
Need check valve that opens at low idling pressure flow so won't back
up too much oil in the sump. Prior to Dave's alert above,
I was only thinking about riding PSI, not lazy slow idle PSI flows.

Peel can't use Commando inline anti-sump valve as may not
hold back oil and I don't want the hose barb fittings plus
there may not be room for its OD to fit in tight area.
Preferred to spend $400 on -6AN fittings-hose-oil filter,
just to please me and eliminate all Jubilee hose clamps.
To bad it mostly can't be seen until peering in close up.

hobot -
Ok yeah that Arkansas gizmo genius and Ozark moonshiners
had real influence on Peel's secret weapon configuration.
Yellar Squid Hunting Submarine quadrex manifold dual regulated
back checked Schrader valved air pressure supply center commando.
Shush, an extra Commando at those controls to relieve some of mine.
Can see his boot bottoms in front of compressor crank case.
Three deck levels to wonder around and service stuff.

LAB, Thats great ,I laughed till I cried. Jim

Yes sir LAB you understand, so are we having fun yet before we rot?
What seems so silly off the wall to rest of the crowd is
just the nuts and bolts of Ms Peel dream machine.
Play this while viewing Peel's British flavored icon fantasy
http://www.youtube.com/watch?v=MCsYDZ2M04M

Green window hatch flips down to reveal pilot in dive helmet.
Water jet cannon does a job of soft bodied squids trying to
get a grip over Peel. Did a chop job on sub tower and guts.


One dial shows reservoir PSI the other regulated PSI.
A fabric hose accessory will provide self and strangers air station.




Ugh, was still too wide so a 2nd plumbing removed brass starboard
fittings but retained the vital air paths and taps.
I had to learn about and acquire Wood's metal-Cerrobend alloy
to avoid kinks and discovered a shade tree and camp fire
gearbox bore fix to boot.

hobot

Hobot

Yeah, Ok, so my Uncle Albert there had a flair for style over function.
Pashaw, I'd rip that flimsy jacket right off in one Hey Watch This.
Srgt. Pepper and sub crew didn't wear them funny shoulder patches
for nothing ya know, me niether.