Oil Pump Removal and Upgrade Kit

SydneyRoverP6B said:
roverp5Bcoupe wrote,...
When the revolution of An hydraulica gears pump rises, the oil quantity also rises.
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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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I think you've argued your way right back to the start Ron .
You refer to a finite space within the gear chamber , which is filled with oil . With the upgrade kit having taller gears to move more oil , and a spacer plate to enlarge the chamber to accommodate more oil . For a given amount of RPM you are moving a greater amount of oil through the same size outlet and into the same oil system with it's restrictions ( main/big end bearings , oil galleries , rocker shafts , rockers etc ) all the things that if in good condition help to create good oil pressure , ( any single one of which in bad condition will see you loosing oil pressure , as i'm sure you'll agree :?: )
So,where can you take your argument from there ?
I'm worried you'll try to convince me their's no Father Christmas , No man in the Moon , or indeed the Moon isn't made of cheese :shock: :D
 
stina wrote,...
think you've argued your way right back to the start Ron .
You refer to a finite space within the gear chamber , which is filled with oil . With the upgrade kit having taller gears to move more oil , and a spacer plate to enlarge the chamber to accommodate more oil . For a given amount of RPM you are moving a greater amount of oil through the same size outlet and into the same oil system with it's restrictions ( main/big end bearings , oil galleries , rocker shafts , rockers etc ) all the things that if in good condition help to create good oil pressure
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That's right Stina, so why should there be an increase in pressure when all else within the engine, clearance wise, remains unchanged? Afterall, the SD1 and all subsequent engines ran with the taller gears, and yet the standard oil pressure remained unchanged. If I am not mistaken, Harvey also advised that running the taller gears would not see an increase in oil pressure. Greater volume of oil moved yes, but not a corresponding increase in pressure.

There was no design change with the gears in terms of rounded edges, but by reducing the end float as you have done, that will see an increase in pressure. If you had set the end float the same, then the pressure would, in all probability, as far as I can see, have remained unchanged.

Ron.
 
SydneyRoverP6B said:
If I am not mistaken, Harvey also advised that running the taller gears would not see an increase in oil pressure. Greater volume of oil moved yes, but not a corresponding increase in pressure.
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I think what I actually said, from what I can remember, is that the primary effect of the taller gears is that they pump more oil, not that they raise the oil pressure, but as a side effect of that there will always be a slight increase in pressure because a greater amount of oil is being pumped into the same available space at any given time, or words to that effect. In other words don't fit them to bump up low oil pressure, cure the underlying problem, but don't be surprised if you find there's a slight increase if you do fit just the high volume kit.
 
FWIW i agree with Harvey... but I'm a happy amateur...

The way I see it to all effects and purposes the outcome of more oil where it's needed occurs, so whether the oil has enough extra volume at a specific point to be able to exert extra force or not is pretty irrelevant.

Rich.
 
Ron,

Sorry but you are acting rather strange because as Stina says you are changing your statements

-What about the link i send about the Bernoulli law not valid in practice, it proves the Bernouilli theory is not correct in practice so your basic statement is simply not valid
-In your previous comment, you mentioned the volume doesn't increase when the rpm increases and now you are saying that the volume increases but that this doesn't mean that the pressure will rise. Everyone knows that if you want to pump a larger quantity of oil threw a hole then the pressure rises compared with pumping a smaller amount of oil threw the same hole.

-Could you simply explain why the oil pressure rises when the engine rpm rises?. That is simply because with increasing rpm, the oil flow increases and this larger amount of oil has to pass threw the same resistance which will increase system pressure .

With bigger gears, you will have a larger oil flow which would give a higher system pressure when the relief valve would not be there. Because there is a relief valve, this means that the oil pressure will be higher only at the lower rpm because the relief valve will kick in sooner then with smaller gears. This means that your engine oil pressure will be better at lower rpm and not at high rpm's because the relief valve will open. I believe this is exactly what Stina experienced (and Harvey states)

Peter
 
Pressure in the system at any rpm is a function of the pump volume/rev and any losses from
bearings/lifters/tappets etc. A tired engine has wear that causes more loss and lower pressure at idle.
If you increase the revs the incresed flow volume will raise the system pressure up to the point that
the relief valve opens and restores set pressure.
Flow is a function of rpm, pressure is governed by the relief valve.

That's my take on it, if I am way off base, please correct me.
 
roverp5Bcoupe wrote,...
What about the link i send about the Bernoulli law not valid in practice, it proves the Bernouilli theory is not correct in practice so your basic statement is simply not valid
Click to expand...

I'll draw reference from one of my text books from when I was last at University. "Physics for Scientists and Engineers" second edition by Dr D.C Giancoli.
"Bernoulli's equation is not a new principle but is a statement of the conservation of energy in a form that is useful for problems involving fluids. As an example, Bernoulli's equation explains the operation of the Venturi meter (the principle that explains the operation of the carburettor), a reduction in area of the throat where the velocity is greatest and the pressure is least.

Bernoulli's equation ignores the effects of friction (viscosity) and the compressibility of the fluid. The energy that is transformed to internal (or potential) energy due to compression and to the thermal energy due to friction can be taken into account by ading terms to the right side of the equation. These terms are difficult to calculate theoretically and are normally determined empirically. We will not pursue it here, but merely note that it does not significantly alter the explanations for the phenomena as described by Bernoulli's Principle."

Ron.
 
I can draw on a statement we use in deepest darkest Dorset , Baffled by bull S**t . Your going round and round here Ron , and loosing site of the issue . Basically we start with a pump of a given size , The P6 pump , which will move a given amount of oil for a revolution . Then we upgrade that pump by enlarging the gears and the chamber they run in , so the pump is moving a greater amount of oil for a revolution . We are putting that greater amount of oil through the same size outlet and into the same size and specification oil system , so , we create more pressure .
If we were to believe your theory Ron , how would we ever make a more powerful pump , and how would we ever increase oil pressure ? If you say by tightening up tolerances , then you are back to the thumb over the out let of the hose theory :!:
I do admit to feeling a bit guilty , i bought this thing up , and it has run away with the original thread . :roll:
 
Keep going Gal, I'm with you, but I'm just going out to put some popcorn on as this one could run and run.... :LOL:



John.
 
Ron,

When you are talking about caburators and venturi, you speak about gasses and not about fluids. This is a very different world also in term of Bernouilli because gasses can be compressed, liquids (almost) not.

You haven't answered my very simple question why the oil pressure is rising with rising engine rev's. You every time change the direction of the subject, forgetting the real discussion and talking big about scientist and their books but keep it simple and just give an explanation on the simple question Stina and myself are asking you. You could ask Bernouilli and Dr.Giancoli to help you

I will withdraw myself from this discussion as i believe there are more serious problems (like what Pilkie is going threw at the moment) and prefer to use the time and energy for more positive issue's like working and enjoying our classic cars.

Peter
 
Ron,

When you are talking about caburators and venturi, you speak about gasses and not about fluids. This is a very different world also in term of Bernouilli because gasses can be compressed, liquids (almost) not.

You haven't answered my very simple question why the oil pressure is rising with rising engine rev's. You every time change the direction of the subject, forgetting the real discussion and talking big about scientist and their books but keep it simple and just give an explanation on the simple question Stina and myself are asking you. You could ask Bernouilli and Dr.Giancoli to help you

I will withdraw myself from this discussion as i believe there are more serious problems (like what Pilkie is going threw at the moment) and prefer to use the time and energy for more positive issue's like working and enjoying our classic cars.

Peter
 
Stina,

There is no need to be rude! I was merely replying to a statement that Peter made re the validity of Bernoulli's principle. He had asked me for a reply, so that is all I was doing.

In any case, I don't make the rules, and it is not my theory. All I was trying to do was to apply science rather that make unsubstantiated comments.

Peter,

I was just sighting a simple example re the carburettor, afterall Bernoulli's principle applies equally to fluids and gases.

Ron.
 
Ron,

Where is the answer to key question: in practice the oil pressure rises with rising engine rpm's, why is that happening according to your theory's?
I will give you the (my) answer. With higher engine rpm's (or with taller pump gears) the delivery of the pump (in cm^3 per second) will be bigger. To let pass this bigger oil quantity the canals, bearings ect causes more friction which leads to a higher system pressure. Hereby you should not forget the presence of the the relief valve. The relief valve causes that the maximum pressure remains unchanged but leads to the fact that the pressure at low rpm's with bigger pump gears will be higher.

Ron, please stick to answering this question and do not involve James Watt, Pythagoas, Ohm or Bell into this subject :D

Peter
 
Please keep it pleasant guys - I'm all for questioning stuff when either you don't understand or it isnt right, but no getting personal please :)
 
Whoa,
Just read through this and couldn't believe the "heated" arguments.

Simple Facts. Pump only gives FLOW. (not pressure)
Pressure is due to resistance( to flow)
Increase in pump capacity ( longer gears) will result in more flow.
Higher revs will result in more flow.
Ergo- more flow, with no change in resistance will result in higher pressure.

The resistance (to flow ) is dependent on the engine clearances. that is the state of (wear) the bearings.

The relief valve is only to limit the max pressure.

The only other factor is the oil viscosity, and that is also temperature dependent.
Don't think I have missed anything.....
Jim.
 
Ron .
I don't consider what i wrote to be rude or personal , a bit cheeky maybe , but i thought you'd be capable of shouldering that . On the whole i respect and on occasion even seek your opinion and your knowledge of the P6 .
However when something is wrong i wont go along with it for the sake of keeping the piece , That's the Emperor's New Clothes theory .
As i wrote above , i was concerned about opening a can of worms here , and apologies to Gerald for ruining his thread ( i'm still really interested to hear how it;s going :D )

Ps , Peter is wright here , we should be out enjoying , rather than bickering ( Who said well you started it :LOL: ) I did a good few miles over the weekend , christmas shopping and cruising the leafy lanes . As usual left the camera at home :D
 
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