i have been working on my oil pump, 44 M20 and read Ians notes on lapping the gears which i have done but noticed that on the steel end plate the little tube on it was loose so i tacked it on, but Ian refers to the ball in it, i dont have one nor can i see where it was supposed to be, maybe some jiggery pockery was going on in Singapore where my bike was demobbed to, or ?
can anyone enlighten me
thanks again

email (option): taybrig@shaw.ca

The tube should have the ball inside it. You should hear it rattling about inside the tube. Occasionally the ball will get stuck in place if the engine is full of old oil/detritus....It is retained by a very light removable wire clip that can be carefully extracted with a pair of snipe nosed pliers. The ball size should be 7/32" dia. No spring is used, suction and gravity move the ball. It sits/seals on a small seat formed inside the lower end of the tube...Ian

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

I've seen 2 or 3 oil pumps where the little tube has come out. Les at Russell's was able to supply just that end plate complete with ball NOS. Ron

email (option): ronpier@talk21.com

no ball or clip or seat just a wee tube, ill fax Russell motors to see if they have one thanks

email (option): taybrig@shaw.ca

The prewar pumps did not have the ball but only a tube, also smaller in diameter than the tube with the ball. Maybe you have one of those?

I believe we concluded here in the past that the function of this ball is there to keep the return side of the pump primed... So no big risk to the oil supply involved when it is not there but think better change it for one with ball when you have the opportunity.

BR Michiel

Hi Kevin

If you need a plate I have a few NOS

I had this issue before

Br

Job

email (option): jonnyob1@googlemail.com

thanks to everyone for the advice and offers, much appreciated, A lazy sunday here raining hard and i was thinking of my pump when i remembered that i thought i saw an old pump in the box of bits that came with the bike, the bike and box were at work but anxious to know i drove to work and yes there it was a greasy old looking pump in the bottom of the box and it had the steel plate with ball in it...good score i thought but then looked closely and cleaned the grease from it....could it be? yes it was an NOS pump packed with grease, i took it apart and cleaned the grease and its definitely a new pump.....so happy

another question is what is everyone doing for a sump plate? mine is a bit bashed and ive seen billet ones with a sump plug

email (option): taybrig@shaw.ca

I've seen some fancy ally sump plates with fins. But I don't think there is room when a sump shield is fitted? Ron

email (option): ronpier@talk21.com

['I believe we concluded here in the past that the function of this ball is there to keep the return side of the pump primed..]

That may be one function of the oil pump base plate ball...however....

From factory worksheet No.604 'Oil pressure valves'....Quote....'There are two ball valves in the system, and both are placed between the tank and the sump to prevent the transfer of oil when the engine is not running'...Ian

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

Hi Ian, Think that quote exactly covers it....:relaxed: . prevent transfer of oil while not running... I would say from the return line as this valve is in the return.

My view is that if the ball is not there or not sealing properly, the return line can drain when not running and the gears will be pumping air until the oil level in the crankcase reaches the gears. So think it is mainly there to get the return flow start as soon as possible to keep the crankcase dry.

where is the 2nd ball?

email (option): taybrig@shaw.ca

In the side cover ?

Kev there is a ball and spring behind the small hex plug at the bottom of the timing cover. It's the first, easiest and cheapest thing to check and or replace if you experience wet sumping. Ron

email (option): ronpier@talk21.com

thanks Ron, there was nothing in there when i removed it......

regarding my NOS oil pump. turns nice and free by hand, and still when 2 bolts are tightened in the mounting holes but..
when i install it and start to just nip up the bolts it gets tight in one area, for 270 degrees its free but the last 90 it gets tight
so i removed it and installed the 2 bolts again and tightened them up and its free through 360 degrees
but same again on installation, i dont want to lap the gears as its so free turning out of the motor and even through the 270 deg
any ideas
thats with or without the gasket
drive shaft is nice and free

email (option): taybrig@shaw.ca