I'm sorry to gloat, but I was pleasantly unsurprised when I stripped my first Hepolite (wassell) oil pump for the above title.
I will admit that I was a little upset when these first appeared on the market as my version has been drawn up for around 10 years now.
First appearance is they look quite well made. After stripping I was not so impressed.
The first thing I noticed was that the shafts are not ground. Then the shaft clearance in the body and end cover is excessive.
This is important because oil will drain back into the engine leaking up the drive shaft when it's left for some time.
I'm not going to run any physical tests as it's just not worth it on a circulating pump. (it doesn't need to make pressure)
Due to end float and excessive clearance on the gear tips in the housing a lot of oil will leak in these areas. Not the end of the world for a circulating pump, but I would expect better.
The pickup/end cap has no provision for a non return valve. Also I think it is made from mild steel. The poor quality 2BA set screws may also distort this cover.
Backlash in the gears is not worth worrying about as I feel the above points out weigh this.
Though I don't believe the tooth form will detract from it's performance, I don't like it. Also the teeth are poorly deburred.

My conclusion is, I really must offer you something better.

I won't fit one, but the choice is yours.

email (option): pes.sales@btconnect.com

Just looking for some good quality new bodies me

I have nos gears, top cap, bottom cap & bolts too

Jo’b

email (option): jonnyob1@googlemail.com

If I knocked up some bodies it could make use of your bits then John.
I'll do them in cast iron as I have a length of bar.

email (option): pes.sales@btconnect.com

The end plate was mild steel on the original pumps...Interestingly the ABSAF high output pump for the Gold Star also has no ball valve in the base plate...Ian

email (option): ian@wright52.plus.com

There are arguments for and against it Ian. One thing for sure is that it’s not easy to machine that fine grove that retains the clip. Personally I’d rather have it. I also like to use a shaft seal, but there is not a lot of room in this pump. I also think the shaft and gear arrangement lends itself to side thrust. I have a solution for this if I made an entire pump.

email (option): pes.sales@btconnect.com

Mark,

I have two of the Hepolite pumps and they are different from yours in the photo.

The gears in both my pumps have a black oxide coating, not bare metal like yours.

The fit and finish of the gears also looks better than yours.

I measured the gear shaft to pump body clearance and it was .0006" for the feed gears and .0007" for the scavenge gears. I would consider less than one thou not excessive???

I next measured the hardness of all the components.

The gears measure at Rockwell C scale 30.

The pickup end plate is definitely mild steel and measures Rockwell C scale 8.

The pump body also appears to be mild steel and measures at Rockwell C scale 12.

Cast iron for the body would probably be a better material than mild steel but as BSA made them out of Mazak and it does not wear out, maybe not necessary?

Before Hepolite started making new pumps I was going to make a new body and end plates out of bronze. But never picked what alloy I was going to use.


Anyway, I have put thousands of miles on one of the pumps so far with no issues.

I expect they use a number of subcontractors for making parts Bruce. I make a few bits for them.
The gears I have, have been hardened. Though an attempt has been made to clean them.
I clean (super finish) all my gears.
I'm pleased you had a better experience than me, I was a bit slow with the first batch.
Even the one I have would work, though I would not sell one without warning the customer.

BTW I have a few bronze end plates I made a long time ago. At the time it was so easy to buy a used pump I didn't think new would sell.

email (option): pes.sales@btconnect.com

Didn't that year go fast!

I'm hoping to finish these in a couple of weeks, mainly because I want one in my engine.

Mark

email (option): pes.sales@btconnect.com

I'm all for choice...However, in my experience to date there have been no negative issues with the Wassell pumps, including the one in my B33...The picture posted of the Wassell pump must be an early one as all now have the anti drain valve in the bottom plate...
Previous tests on original used pumps (so with varying degrees of wear) indicate that when pumping against a 'blind' gallery the gears start to back feed at approx. 60 psi...The anti drain valve in the cover lifts of its seat at 7 psi...What gear end float figures were you getting when you measured the Wassells pump?...

Also, how much will your pumps be when they come to market?...Ian

email (option): ian@wright52.plus.com

Here's one of the pump test results...Ian

email (option): ian@wright52.plus.com

A lot of the leaking back is caused by excessive spindle clearance Ian.
Remember in a roller bearing application it's just a circulating pump.

Sorry I didn't make any notes on the previous pump as it was so bad I didn't think it was worth it.
There has been a new batch made and I will buy some for curiosity.

As I have already made a large investment in these I will continue.
At least I know these will be fit for purpose and more.

Mark

email (option): pes.sales@btconnect.com

['At least I know these will be fit for purpose and more...']

I'm sorry, but the Wassels pumps are plainly fit for purpose as they are already in service and working successfully in multiple engines...

Whilst I accept you feel you are going to produce a better product, that doesn't mean everything that came previously isn't fit for purpose...
There are also many BSAs running around with worn and corroded original pumps (the majority in fact) that are still working despite being decades beyond their designed lifespan and not operating at 100%...

I regard the Wassels pumps as a viable upgrade from a worn original and I've yet to see any hard evidence to the contrary...Ian

email (option): ian@wright52.plus.com

I look forward to seeing the new improved pumps then Ian.

email (option): pes.sales@btconnect.com

The prewar pumps also did not have the ball valve in the bottomplate, so the bottomvalve looks not strickly needed for the oil supply

Not sure, but I while ago I came to the conclusion that it is there to keep the returngears primed with oil so that it directly starts pumping when engine is running.

In theory, when no bottom valve is fitted, the returnline including the gears will drain and run dry when started again, consequently create no or very little suction untill the oillevel in the crankcase reaches the gears.

BR Michiel

Mark,

I think you are looking for a solution for a problem that does not exist. The factory BSA pump in my bike was in very bad condition when I got the bike. And yet after many years still had it's original big end bearing which has no measurable wear.

I have a complete machine shop at home and could have made a new pump and intended to until Wassell decided to make new pumps. Is the pump the best that could have been made, no, I can do better machine work than them but I am not working to a price point. Wassell says the pump body is made from cast iron but it looks like mild steel to me. As for the gears, I would have heat treated them to be harder than what they did and yes the gear shafts should have been ground. And the end plates should have been made out of a different material.

If your pump which I am sure will be better made than Wassell can be sold at a similar price, you will put them out of business. Now a pump that sells for £500 is not going to have many sold unless you sell it to Goldstar owners as they will pay any price.

Having read many of your posts, you certainly know what you are doing and had you been making pumps back when I bought my Wassell pump, I would have bought your pump instead. The lack of the ball check valve is certainly an issue with the Wassell as the bike is going to wet sump from sitting which mine does. So I may be one of the first customers for your new pump.

As Ian has stated, there are many bikes with the Wassell pump on the road and it works! The Wassell pump in my bike has thousands of miles without issue and is definitely better than what BSA made.

Anyway I await to see what you come up with.


I will shut up for now. I have another hour sitting by the heat treat oven at midnight to quench a big end pin for a 1929 AJS. No parts are available so have to make everything.

Bruce, Ian,
I have a pump in my now grubby hands and they have indeed improved.
To a point where I'm happy not to issue a warning about them.
As mentioned the shafts being turned rather than ground.
On modern machinery it's possible to eliminate grinding with some jobs.
The only comments I would make is that I found the gears not concentric to the shafts,
but only by a small amount.
Not enough for me to make mandrels to put them on the gear tester.
Another thing to remember and the same with the original pumps,
careful assembly is required for the gears to turn freely.

What am I doing different?
I'm changing the shaft and gear design to one that is more in common with the last pumps produced by BSA.
Also I hope to improve the ease of assembly.
If it looks ok when done there will also be a shaft seal to help with draining back when stored.
This is not a new project, sadly one shelved along time ago.
Once completed it also allows for a competition version to be made with ease.
How will it be priced, sorry it will have to be a little more than the Wassell pumps we sell due to expectations.

Mark

email (option): pes.sales@btconnect.com

I'm looking forward to seeing the results of your efforts...I bought an ABSAF high capacity pump for my Goldie so for me it's not all about price...I currently have a project underway which might benefit from a higher spec. pump....Ian

email (option): ian@wright52.plus.com

Presumably it's the case with most manufacturers using similar bottom-ends and identical oil pumps on their roller-bearing SV and OHV engines, that the SVs can cope quite well with a pump that might be less than optimal in terms of delivery ?