Oil Pump Removal and Upgrade Kit

SydneyRoverP6B

Well-Known Member
Staff member
#61
Stina wrote,...
if you force a bigger volume of oil through the same hole you will get higher pressure
How did you come to that conclusion Stina? Reason that I ask is if that were true, then it would defy the laws of Physics.

The oil is for the purpose of this discussion incompressible, given the temperatures and pressures that it experiences. The pressure that registers on the gauge is a function of the resistance to the flow. The standard gears will for each revolution move a certain volume of oil through the engine. The taller gears for each revolution will move a larger volume of oil through the engine, but the oil cannot be compressed so rather than forcing more through a given space, the oil travels through the engine a greater distance.

Ron.
 

stina

New Member
#62
SydneyRoverP6B said:
Stina wrote,...
if you force a bigger volume of oil through the same hole you will get higher pressure
How did you come to that conclusion Stina? Reason that I ask is if that were true, then it would defy the laws of Physics.

The oil is for the purpose of this discussion incompressible, given the temperatures and pressures that it experiences. The pressure that registers on the gauge is a function of the resistance to the flow. The standard gears will for each revolution move a certain volume of oil through the engine. The taller gears for each revolution will move a larger volume of oil through the engine, but the oil cannot be compressed so rather than forcing more through a given space, the oil travels through the engine a greater distance.

Ron.
So you are saying Gerald wont see an improvement in oil pressure then Ron ? The original reason for him dong the conversion , Oh deer !
I'm not very academic , certainly not a physics expert .
When i did mine i went from around 10/15 psi hot idle to 20/25 psi after an 80 mile run , so , where did that pressure come from :?:
I agree , the reason for the conversion is increased flow , but as you say the oil will travel further through the engine. Because it is under higher pressure !
Turn the tap on in your kitchen , a given amount of flow , can you argue that :?: Then put your thumb partially over the outlet , a strong jet of water , able to travel big distance , without turning the tap on further , can you argue against that :?: Higher pressure for the same flow :wink:
I think i've given Gerald good advice , based on work i undertook on my own motor .
The question was can anyone help with the measurements of end float on the gears ?
Since writing , i have dug out my , fitting instructions , and we need to be between .001" minimum or up to .005" maximum
:wink: :D
 

GRTV8

Well-Known Member
#63
Guys
I bow down to your personal experiences with the P6 .
I can't argue against anything you two say as Ive followed both of you in your endeavours to improve and upgrade the P6 overall .

If it works and the results give someone a better nights sleep , and its a job even a numba like myself can attempt , then it must be OK.

When my grandies ask me a question that I struggle with , the answer they get " its Magic "

Ive been absolutely grateful to Stina and others for their instant and encouraging replies as I would never have attempted this upgrade without all this sage advice .
I went back through old threads on "oil pressure drop" and there are screeds of Q and A out there . More recent answers suggest the oil pump upgrade kit as more and more of us go that way - all thanks to you guys .
I know for sure others following this thread will now "give it a go"

So keep up the good work and if you see the need to use science in the reasons for doing something then its magic to me too .

Ive met all sorts of minds over my many years and marvel at how we are all so different yet on the outside look basically the same - more Magic

Back to the thread
I can't do anymore to the pump til I buy some gaskets to play with until I get the same result you good guys came up with .
Im nearly there .
Thanks again
Gerald
 

SydneyRoverP6B

Well-Known Member
Staff member
#64
Stina wrote,...
but as you say the oil will travel further through the engine. Because it is under higher pressure !
Turn the tap on in your kitchen , a given amount of flow , can you argue that Then put your thumb partially over the outlet , a strong jet of water , able to travel big distance , without turning the tap on further , can you argue against that Higher pressure for the same flow
Hi Stina,

There is a fundamental floor in your argument in that you are associating an increase in flow with an increase in pressure. The analogy that you gave with respect of the hose is a case in point. Although it seems straight forward, when the flow of water (velocity) increases from placing your finger partially over the outlet, the pressure actually drops, it does not increase.

Now I know that seems completely wrong, but as I say, the laws of Physics tell us that is indeed what happens. Bernoulli's principle states.."Where the velocity of the fluid is high, the pressure is low, and where the velocity is low, the pressure is high". Applying the laws of fluid dynamics to engine oil further complicates matters as it introduces a material which is quite viscous, certainly in comparison to water.

http://hyperphysics.phy-astr.gsu.edu/hbase/pber.html


When you did your oil pump conversion, if you reduced the degree of endfloat over what it was originally, and I am talking only by thousands of an inch, then the pressure will increase, as you have increased the resistance to flow. New gears will also improve the pressure as they won't exhibit any wear.

Ron.
 

stina

New Member
#65
Hi Ron .
Lets agree to disagree for the time being and not foul up this thread , or loose sight of the final goal . I did write that i was afraid of opening a can of worms with the pressure argument .
More important at the moment is to sort the acceptable amount of end float on the pump as the next step . I posted yesterday what was written on my original fitting instructions , I'd like someone to reference that with the W/M and confirm i'm right . I'm not overly confident giving that advice . although i got mine right , that was mine and would be my problem if it were wrong .
I think there is a good bit in Vaultsmans thread about measuring and setting the end float :D
 

GRTV8

Well-Known Member
#66
Stina You are right the end float should be between .001 to .005" Both stated in the WM and kit instructions .

Im nearly there with my new pump set up .
Cleaned up the relief valve and put in a lower rated spring to what I nearly tried to use . It is working a lot freer in the chamber now . After reading those past oil pressure threads I now think my valve may have been sticking sometimes .

I just need to get another gasket to see if that will give me more end float , as at the moment I have almost nothing , which won't work once assembled .

Now just for argument sake . If I set the end float to say .002" and then torque the whole unit down , won't that alter the end float measurement again through compression on the gaskets or will that be too insignificant to worry about ?
Gerald
 

stina

New Member
#67
Hi Gerald .
Re reading my instruction sheet , it says to assemble the whole thing , torque the cover to 10 lb'ft then measure for end float .
Obviously then you can't get a straight edge across the gears as the cover is on , so i assume they mean you to measure the end float at the top of the shaft . Not easy without a drop gauge . I seem to remember i torqued the cover down a little less than specified , enough to compress the gasket , then removed the cover carefully and measured , kept changing gaskets until i was happy with the clearance , i'm sure i ended up with a standard land rover gasket above and below the spacer plate .
Are you planning on spinning it up to pressurize the system before you start it with the drill and tool in the pump drive method ?
I did to ensure i had pressure , very easy to make up a tool to do the job , i used a long flat blade screw driver shaft with various bits of rubber pipe as a shroud to keep it lined up on the pump drive . You can buy the proper tool from different outlets , ( Rimmer Bros for example ) but it's easy to make from bits you'll find lying around your Man cave :D
 
#68
but the oil cannot be compressed so rather than forcing more through a given space, the oil travels through the engine a greater distance.
- how can it go a greater distance ? You've lost me

I did A level Physics when I was a boy and there's some formula about pressure and volume but I can't remember what
 

stina

New Member
#69
Not heard from you for a while Gerald , are you having trouble ? Or are you wandering around lost and dazed in your Man cave ? :lol:
 

GRTV8

Well-Known Member
#70
Hello Stina
Im alive and well . Always lost and confused .Just ask my wife .
Ive got to the stage where I'm waiting on this bloody timing chain and gears to turn up . Rural delivery and couriers are absolute B******d's . They wait til they have others in the area to deliver to . An overnight can take 8 days .
In between farm work I have been playing with the P6 . Sanding , prepping and spraying anything that is factory black .
Also have some aluminium polish and have buffed up anything aluminium .
Its all looking rather bling under the bonnet .
The oil pump is running freely after adding repro gaskets and discarding the V8Tuner ones [on the right ].
Its all primed up with vaseline .
New cover and water pump gaskets at hand , so all set to go there .
Tomorrow Im off to Oz for a few days . My son took out the state chef awards and I would like to give hime a big hug .
That gear and chain had better be on my doorstep when I get back .
Thanks for thinking of me in my oil pump drama .
 

Attachments

stina

New Member
#71
Ah good , was worried you'd fried yr brain with all this and you were in there lost in a daze . So a few hours work'll see it running when the chain turns up . I hate waiting for bits from the postie , it's usually something i've ordered for my Husband , or he takes it away again coz their was no one here to sign for it :roll:
 

SydneyRoverP6B

Well-Known Member
Staff member
#72
DaveHerns wrote,...
how can it go a greater distance ? You've lost me

I did A level Physics when I was a boy and there's some formula about pressure and volume but I can't remember what
The formula that you were probably trying to remember is P = nRT/V, which is the ideal gas equation, where the pressure is inversely proportional to the volume.

In respect to "how can it go a greater distance?", the tall gears for each revolution will deliver a greater volume (quantity) of oil. As there is no compression of the oil, the density does not increase, therefore given there is a greater amount entering the engine per revolution, it follows that if must extend further into the engine. Consequently, the oil circulates through the engine more quickly for a given engine speed.

Ron.
 
#73
To add my idea's about the discussion, I believe that the efficiency of the new pumps is better if the endfloat is oke. I recently overhauled my RV8 (SD1 unit for my P5B) and replaced the oil pump gears. When i compared the old and new gears, i noticed that the tips on both sides of the old gears teeth(rh on the picture) were rounded of more than the new ones (lh on the picture) . I believe there is quit some pressure loss because oil can escape there and that is why the new pumps have a higher pressure.



Ron,

I believe P x V = R x T is there for gasses and not for liquids, am i right?. Also the Bernoullli theory assumes there is a laminair flow and no turbulence and no frictional losses and in practice this is not. Also i believe that (speaking in Bernoulli terms) the energy density of a "new" pump (with higher volume and pressure) is higher which results in a higher pressure in the engine.
In your thoughts the energy density of the old and new pump is identical but this is not oke. So i believe Stina is right in believing that a higher flow causes a higher pressure

Peter
 

GRTV8

Well-Known Member
#74
Re: Timing gear " SENT " yeah right

AAAH !!!
I DONT F*&*N BELIEVE IT ,
The guy I bought the timing gears and paid courier postage for on the day [ 15th ] just emailed to say " thanks for your business - goods sent ". [ 21st ]
its taken him six days to get his arse into gear let alone my gears in the mail .
I emailed him straight back and had a tantrum on his head .
He emailed back "sorry - didnt think it was urgent " !!!
Bloody Nora
Gerald
 

SydneyRoverP6B

Well-Known Member
Staff member
#75
Hi Peter,

roverp5Bcoupe wrote,...
When i compared the old and new gears, i noticed that the tips on both sides of the old gears teeth(rh on the picture) were rounded of more than the new ones (lh on the picture) . I believe there is quit some pressure loss because oil can escape there and that is why the new pumps have a higher pressure.
I agree, as I wrote that above. :wink:

I believe P x V = R x T is there for gasses and not for liquids, am i right?.
PV = nRT or P = nRT/V is the ideal Gas equation, as I mentioned above. My reply was directed to Dave Hern's thoughts and his reference to school, and this is the equation that you learn in school science. :wink:

Also the Bernoullli theory assumes there is a laminair flow and no turbulence and no frictional losses and in practice this is not.
That is true.

Also i believe that (speaking in Bernoulli terms) the energy density of a "new" pump (with higher volume and pressure) is higher which results in a higher pressure in the engine.
In your thoughts the energy density of the old and new pump is identical but this is not oke. So i believe Stina is right in believing that a higher flow causes a higher pressure
The floor in that argument is if that were true, why did the SD1 engines which ran with the taller oil pump gears, deliver the same or indeed less oil pressure than the P6B engines with their smaller gears?

Ron.
 

stina

New Member
#76
Re: Timing gear " SENT " yeah right

GRTV8 said:
AAAH !!!
I DONT F*&*N BELIEVE IT ,
The guy I bought the timing gears and paid couier postage for on the day [ 15th ] just emailed to say " thanks for your business - goods sent ". [ 21st ]
its taken him six days to get his arse into gear let alone my gears in the mail .
I emailed him straight back and had a tantrum on his head .
He emailed back "sorry - didnt think it was urgent " !!!
Bloody Nora
Gerald
Go on Gerald have a good rant , that drives you mad eh ? I think anything auto related is urgent , it goes without saying you ain't going far without a timing chain and gears :shock:
 
#77
Hello Ron,

I am cheating a bit as i have a bachelor in Engineering and have worked for Bosch Rexroth during the last 5 years. Not in their hydraulic pump department but in their large hydraulic cylinder department but still had to deal with hydraulic systems in general.
In almost every hydraulic system there is a relief valve for regulating the pressure. This relief valve exsist of a hole which will be fully opened if the required pressure is 0 or low and will be closed when a higher pressure is required. This valve functions more or less identical to the restriction in your Bernouilli picture. If the gap is small the pressure will rise, if the gap is wider the pressure will be lower. On your rover is also a relief valve. This is an opening which will become wider as pressure rises and will be fully closed at lower pressures. According to your theory the valve would be

In other words: how can you explain that with rising RV8 engine revolutions, the oil pressure always increases. I believe that this is caused by the increased volume which gives a higher pressure in the system. According to your theory the pressure would drop

I also found a statement that the Bernouilli is only theory and doesn't work in real live: http://www.engineersedge.com/fluid_flow ... uation.htm

That a Sd1 gear pump (if this is true) has a lower pressure can have several causes:
-pump end float tolerances may have changed
-gear tips could be rounded more on SD1 pumps
-then there are gaps/tolerances in the bearings on crankshaf, camshaft, lifter galery. If the tolerances are higher then the system pressure (even with taller gears) can be lower. I am not speaking about wear tolerances but speaking about the initial construction tolerances. Rover could have set these a little wider because if tolerances are set wider, the construction price of a part will be cheaper.

Regards

Peter
 

SydneyRoverP6B

Well-Known Member
Staff member
#78
Hi Peter,

Yes indeed there is an oil pressure relief valve within the oil pump front cover. My understanding is that the valve only opens when the pressure pressure reaches 60psi. At lower pressures, the valve remains closed.

In other words: how can you explain that with rising RV8 engine revolutions, the oil pressure always increases. I believe that this is caused by the increased volume which gives a higher pressure in the system.
Oil pressure is a function of resistance to flow and viscosity. You have indicated that you believe that the pressure increase with increasing revs is down to an increased volume. I would ask, how does the volume increase when the quantity of oil circulating through the engine remains static?

Ron.
 
#79
Hello Ron,


You are making a huge misstaken by assuming that the oil quantity is static because it isn't. When the revolution of An hydraulica gears pump rises, the oil quantity also rises. Hydraulic gear pumps specifications always show oil quantity per revolution which means that If the revolutions rises, the oil quantity also rises. the efficiency of a gear pump lowers a little when revolutions rises but this is less then 10 procent differente compareerden to lower revolutions.
You can even see this by removing your valve covers and let the engine run. If you rev the engine, you will see more oil drip from the valve gears then when the engine is idling

Peter
 

SydneyRoverP6B

Well-Known Member
Staff member
#80
roverp5Bcoupe wrote,...
When the revolution of An hydraulica gears pump rises, the oil quantity also rises.
Hi Peter,

Would you mind expanding on your point above please?

Overall, the volume of oil within in the engine does not change, that was the point that I was making about being static. Given that there is a finite space within the oil pump gear chamber which is filled with oil, how does the volume of oil within increase as the gears turn with increasing speed? I can appreciate that over a specified time frame a greater volume of oil will pass through the chamber with higher engine revs.

Ron.
 
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