Author Topic: SRM Replacement Oil Pump  (Read 3479 times)

Offline Sluggo

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Re: SRM Replacement Oil Pump
« Reply #30 on: 19.11. 2017 07:31 »
Colin to be more specific regarding your question, I can directly say I have never owned a SRM pump, or seen one in person, more importantly have not reviewed the tech data related to flow, or volume.   But based on info I have heard and read, the 2 main benefits of the SRM is better quality of components, as well as ***I BELIEVE*** More volume.
The same can be said for the cast iron A65 pumps and both the blog I posted a link to, as well as reams of info I have read the Cast Iron A65 pump is the ideal BSA should have gone with to begin with, and same as what ***I BELIEVE***About the SRM pump is better materials, construction and more volume of oil.

As to fitting an A10, dont quote me on that but i saw references on this forum and others that it is possible to combine parts of the cast iron A65 pump with the A10 and make a A10 super pump.. but i have not confirmed that but something I am looking into.  But I would agree with you and my point is pressure is not that important, but volume is and consistent volume at that.

A good metaphor Is I enjoy building engines and American V8s commonly.  Depends on the application, but one constant I always strive for is optimizing the oil system and one product I always use is a Melling High Volume oil pump,. Take the Chevy V8 for example, Chebbys have stock an excellent oil pump and design right out of the box,  And while I dont build extreme race engines on the street anymore. (Not much fun to drive or own) I expect to flog the heck out of any engine.  So the Melling is a well engineered Oil pump and it appears to me, very similar to what the SRM pump offers.   The Melling is designed for a nice boost in volume but not too much, too fast, or too little.  (Goldilocks)   When installed I see a typical boost in pressure of 20-40% and Pressure was never the goal but it is a symptom and byproduct of the larger amount of oil volume.
In another topic I talked about interviewing the engine guys and crews for the IRL-CART race teams during their transition to synthetics.  In their case with the Chevy Illmore engines the synthetics ran with LESS pressure but more volume which was a big benefit due to the difference between a synth & Dino oil.  As well, those were multi million dollar motors and they had ZERO oil failures the previous season with the synthetics & if they had, The oil company promised to pay for the engine.

These old BSA engines dont need rocket science, but an interesting issue DOES exist.  I bet,, In fact I would wager if you COULD compile detailed data for Engines say... 1955 and take that same engine with a few upgrades and modern products such as superior synth multi grades oil, a return line filter and a high volume quality oil pump how would they compare under todays conditions???

I believe I know the answer.. I know a couple Hyper mileage guys with vintage Iron,, and they get obscenely high mileages out of these same clunky old engines.  Not only are they mechanically sympathetic, but the difference in materials means they can get extreme mileages between major overhauls or service that was never possible back with the same engine in the 1950s.

In Aviation school one of my instructors said the dumbest thing shops do is have a new guy doing engine tear downs.  Instead you should have one of the most skilled and knowledgeable do it.  Forensic engine analysis.  A worn engine will tell you vast reams of data if you look carefully and can interpret the info.

Besides the SAE papers,, of which there are thousands and thousands it appears, there is a number of forums that argue over this stuff. I used to Seagull a few of them but its exhausting.    One of the biggest debates I ever saw blow up was a discussion of oil shear under gear tooth changes in Gerotor style oil pumps (Which BSA have)  Some of the discussion got quite heated. 

This forum is one of those... See: https://www.engineersedge.com/engineering-forum/forum.php

You get interesting exchanges like this:

"Do a you have a geometric mathematical proof for "the explosion at the base of the closed cylinder doesn't just blow past the cylinders, but pushes them apart. "?

You need to expand on the physics explanation and evidence to move forward..
---------------------------
In the phase, or phase space, of the evolution of the combustion, it looks like beneath the cylinder at combustion a cross section of a torus, but what is actually a nonlinear oscillation that looks like this: https://www.google.com/search?q=osci...qgtdkG79s11qM:
So it is a nonlinear oscillation that produces the flame pattern.

I went to the link and it mentions a double well structure. The flame itself produced between the two hemispheres looks like a double cone, that looks like this: https://www.google.com/search?safe=s...QDgFxUKFLSFqM:
------------------------------------
This is not a mathematical proof of the concept. You need to model the physics and associated math... I don't think you're conceptually understanding the acting pressures correctly...
____________________________________
See? Flame trolls and articulated debate.. sheesh..  *fight*

But there is some really interesting ideas that have come out in the last 10 years challenging past beliefs..

See: http://papers.sae.org/2013-01-1643/

" Study of Motor Oil Cooling at Low Reynolds Number in Multi-Port Narrow Channels"

But perhaps this is all for nothing,, after all, The UK is probably going to ban these old clunkers anyway..

See: https://www.marketwatch.com/story/uk-to-ban-new-diesel-gasoline-cars-by-2040-2017-07-26?utm_source=fark&utm_medium=website&utm_content=link&ICID=ref_fark

The internal combustion engine was dealt another blow on Wednesday when the U.K. pledged to ban the sale of new gasoline and diesel cars by 2040, following a similar move three weeks ago by France.

While far from a knockout, the decisions by the U.K. and France--which together account for about a third of new cars sold in the European Union--are among the most aggressive moves by governments recently to legislate away the traditional gasoline- or diesel-burning engine, which has been for more than 100 years been the preferred method of powering passenger vehicles.

For decades, governments have struggled to rein in the pollutants the engines caused but with few alternatives have balked at banning them outright.

Volvo's recent announcement that it would only sell fully electric or hybrid cars starting in 2019 and the arrival of Tesla Inc.'s $35,000 Model 3 have put further pressure on gasoline and diesel engines.

"We can't carry on with diesel and petrol cars, not just because of the health problems, but also because the emissions they cause will accelerate climate change," U.K. Environment Secretary Michael Gove said in an interview with the British Broadcasting Corp.

More on that page.........



Remember that any advice received on a free internet forum is generally worth about 1/2 of what you paid for it.
We overcharge every 3rd customer to pass the savings onto you.
You can have High Quality, Low price, and fast turnaround. Pick any 2, Never all 3 at the same time.

Online JulianS

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Re: SRM Replacement Oil Pump
« Reply #31 on: 19.11. 2017 08:53 »
The drive ends are completely different between A10 and A65 pumps. To use the A65 iron body you would need an A10 drive end.

There was a very nice cast iron A10 pump made in the mid 1990s by Stuart Digby Developements, used the late A65 gears and had the o ring seal and shaft which extended into the drive end.

A real quality item but I dont think many were made.

I bought one in 1994 - cost new then almost £200.

Good parts seldom come cheap.

Online JulianS

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Re: SRM Replacement Oil Pump
« Reply #32 on: 19.11. 2017 09:14 »
Worth reading this thread includes side by side photo of A10 and A65 pumps.

https://www.a7a10.net/forum/index.php?topic=5829.0


To clarify - both pumps rotate in the same direction - different worm drives needed to maintain the direction due to the different position the drives go into the pumps.

Online Triton Thrasher

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Re: SRM Replacement Oil Pump
« Reply #33 on: 19.11. 2017 09:24 »
I was once told that they were too efficient and because they circulated the oil so quickly it had less chance to cool down.

I think there are folks here who use them and rate them and will discount the above as BS. They'll be along shortly I'm sure.

The bigger or better pump maintains oil pressure when the oil is hot and thin and clearances may have opened up with expansion.  When full pressure is reached, excess pumped oil passes through the relief valve to the sump and is scavenged back to the tank.

If that fills you with overheating terror, stay away from the bigger or better oil pumps.

I can’t say Sluggo’s quote about bouncing petrol droplets convinces me of anything except that he likes to type.

Online mikeb

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Re: SRM Replacement Oil Pump
« Reply #34 on: 19.11. 2017 09:44 »
Quote
Are there any problems in fitting the pump?
i was very sad when fitting a srm pump to my a10 as i could no longer look at it and marvel at the beautiful blue colour. almost as sad as enclosing my new thunder rods from view. crazy money but after a $$++ rebuild I thought of it as cheap insurance. would do it again
New Zealand
'61 Super Rocket  - '47 B33 -  '18 Triumph Street Triple RS

Online Greybeard

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Re: SRM Replacement Oil Pump
« Reply #35 on: 19.11. 2017 09:53 »
i was very sad when fitting a srm pump to my a10 as i could no longer look at it and marvel at the beautiful blue colour.

Great marketing. It certainly looks like it might be made of magic!

Online mikeb

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Re: SRM Replacement Oil Pump
« Reply #36 on: 19.11. 2017 10:00 »
Quote
It certainly looks like it might be made of magic!
anything that keeps my a10 running smoothly IS magic!
New Zealand
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Online KiwiGF

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Re: SRM Replacement Oil Pump
« Reply #37 on: 19.11. 2017 10:52 »
I was once told that they were too efficient and because they circulated the oil so quickly it had less chance to cool down.

I think there are folks here who use them and rate them and will discount the above as BS. They'll be along shortly I'm sure.

The bigger or better pump maintains oil pressure when the oil is hot and thin and clearances may have opened up with expansion.  When full pressure is reached, excess pumped oil passes through the relief valve to the sump and is scavenged back to the tank.

If that fills you with overheating terror, stay away from the bigger or better oil pumps.

I can’t say Sluggo’s quote about bouncing petrol droplets convinces me of anything except that he likes to type.

Yep, sluggo needs to spend more time in the shed, less on the keyboard  *whistle*
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Offline BSA_54A10

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Re: SRM Replacement Oil Pump
« Reply #38 on: 19.11. 2017 11:08 »
once again, Sluggo, has produced some really interestig reading, which is why I like a lot of his postings.
But again I would scream "Relevance Your Honour".
There are so many engineering shortfalls in our engines , arguing obscure points of physics is some what a moot point.
The original A7-10 oil pump was up to the job right up to highest performance variation made.
Now like everything else it wears out and new ones have not been made for decades.
If you are going to tool up to remake an obsolete product it makes good sense to upgrade that product particularly if the upgrade does not cost any more than remaking an exact copy of the original item.
Thus the SRM oil pump is a sound item in both engineering terms and in marketing terms.

As for oil pressure being irrelevant , there are of course limits.
Too little pressure and the oil will not be able to float the bearings.
Too much and the flow of the oil itself will erode the surfaces that it flow across.

Bike Beesa
Trevor

Offline duTch

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Re: SRM Replacement Oil Pump
« Reply #39 on: 19.11. 2017 22:36 »

 
Quote
Why are studs better in these respects? If they are, why do SRM supply socket screws?


As stated above, threads can wear with constant use, but moreso (mostly) under tension in or out.
 The finer BSC thread gives a better purchase for less effort, and in theory (my mind) will withstand vibration-loosening better.
 My plan (When necessary) is to use a locknut pair to undo the screws after slackening the holding nut.
  To those who say "fit and forget",  I say **** *eek***  (not really a good idea to forget stuff like that- *Note to self; the Gutzzi pump is buried a bit deeper).
 Do you ( 'second & third persons' ) never open the cover to check your dynamo hum (drive-chain/belt), or drain the ~70ml of oil when doing an oil change, or even check the magneto nut is tight?

 So GB, where does that put us?
 Before installing my Cast-body pump, I think I may have run kero or petrol through to make sure it  was clean and prime with fresh oil to ensure function, but didn't do what I usually do with a new toy and pull it apart to see how/why it works (so I know what did do when it doesn't work when I put it back together).... now I really wanna know what's in there...

 In addition, I read a mention on another site while searching for replacement filter heads, that; ".. the only part of an engine that receives unfiltered oil is the Oil pump..." ....
Have a nice day
 
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Online Colsbeeza

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Re: SRM Replacement Oil Pump
« Reply #40 on: 20.11. 2017 02:57 »
Thanks Sluggo and others,
I am sure that when I "fixed" my pump 25 years ago, I was unaware of all these issues (having no internet). The motor was undamaged, but bearings worn beyond acceptable limits. I dismantled the oil pump and used 1200 Wet & Dry emery paper on a sheet of glass to work the end plate until most of the grooves and wear was removed.  If memory serves me correctly, I think I also did the same to the end of the pump which mates with the end plate, to make allowance for the wear behind the gears. When assembled, it was a little firm, but not too alarming. And I did remember the little fibre washer spacer under the end of the pump.!
As I am sure it was the original pump from the bike, I wasn't too concerned about other issues and certainly not alignment of components. Anyway, it is in the bike and pumping a treat.
However, the outcome of all this theory on this Forum is that I may have contracted "Oil Pump Paranoia" - one who watches the oil pressure gauge constantly until I run it off the road, or at the very least rob me of all riding enjoyment.
So if I go down the SRM route in the absence of other alternatives, I will rely on the experiences recorded in the Forum -
In summary - Most owners with SRM pumps have not experienced any problems, nobody has said that the increased oil flow has worn out the bushes, nobody has reported that bubbles have destroyed their motor. Most have relaxed their concerns after a time. Perhaps all have been very satisfied with the outcome. So who am I to argue with that.?
And one doesn't have to get too theoretical to understand that the increased flow potential should improve bearing float/support when motor is hot and under load and thus reduce wear much more than extra friction may increase wear.??
I accept that the pressure relief valve setting then becomes quite important, so I will be watching that. 60 psi you say.??
In the meantime, I have just re-joined my local Vintage Motorcycle Club after an absence of 11 years, but belatedly realised that for all new members I must attend 3 monthly meetings before members vote to accept my application. The first was 4th November. Then - the machine examiner will pass or fail my bike before I get to ride it and sort out any issues. So all going well, I may be able to report progress about the end of January. I suppose I can fill in time with a few outstanding jobs - like replacing the "new" but 25-year-old Cheng Shin tyres I stuck on it then - just ordered Avons.!
One issue though - I read but cannot find the reference to oils on the Forum, where Richard "Orabanda" mentioned that he used Penrite 25W-70 oil. It sounded perfect to me, so I have filled my bike with it, assuming that it's 25W rating was less viscous that a straight 30 monograde - but just read it's Data Sheet that it's viscosity is 290 CSt at 40 DegC whereas other oils generally are only about 100 CSt. That now seems way too high, although it pumps OK - plenty coming back via the Return. Something isn't hanging together there, and I don't want to run it until I can sort it out *dunno*. I knew I should have done more research.!! Can any one tell me where that reference is? or can Richard comment.? I am sure he would have done the research.!! I have 10 litres spare at A$50 per 5 litres, so don't want to waste it. Happy to pursue that on an appropriate Oil forum. Second thoughts - I will post this bit on an appropriate Oil subject on the Forum.
Cheers
Col

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Online orabanda

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Re: SRM Replacement Oil Pump
« Reply #41 on: 20.11. 2017 06:07 »
Hi Colsbeeza,
Penrite used to call this oil "Enduro".

I have attached a data sheet. As they spell out, it has high zinc content (excellent for our pushrod bikes), and is designed for Hardly Davidsbums and BSA twins.

I have been using it for 20 years; no engine rebuilds yet!

Re the SRM pump, good kit; superior (lower wearing) materials to the 70 year old BSA pumps. If they produce more flow, that is to the advantage of the engine, in both the bearing delivery (pressure), and scavenge stages.

The parasitic power loss is insignificant, but greater flow rate to the crankshaft will result in higher oil pressure when the engine is hot, and greater flow return is likely to aid cooling.

Richard

Online Colsbeeza

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Re: SRM Replacement Oil Pump
« Reply #42 on: 24.11. 2017 11:49 »
Thanks Richard,
Enduro has the same specs, so must be just a name change.
I have had some advice that for running in, a mineral oil with no additives except high Zinc is ideal. I might lash out for some Penrite Running-In oil, which has high Zinc. It is 15W-40, so I imagine putting up with wet-sumping until run-in is complete. I have a new camshaft and cam followers, so a bit wary of running without Zinc.
Colin
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Offline peter small

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Re: SRM Replacement Oil Pump
« Reply #43 on: 30.12. 2017 18:58 »
Fitted SRM pump on my 1954 Road Rocket
Great delivery much better than original although it still wet sumps.
Did ask SRM about wet sumping they said it still would the pump would not correct it,
They told me the truth impressed,
BSA ROAD ROCKET 650cc 1954
Norton commando Roadster 750cc 1972
Triumph T140 Silver jubilee 750cc 1977
Honda Pan European ST1100  2000
Honda C90 1990

Offline cableguide

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Re: SRM Replacement Oil Pump
« Reply #44 on: 01.01. 2018 17:23 »
And as I always say to anyone spending big bucks on these superb pumps....spend time cleaning out the hard gritty gunk in the oil tank nooks and crannies....I always take mine to the garage after a poke about and lengthy soaking and blast the insides with the power wash....
Nothing worse than doing all that work only to find those little bits of crud have broken free and scored up the pump chambers.