Massive oil leak - still!!

[Harvey_Mushman]

Hello, last year i bought an 1959A10 which I was assured had been rebuilt well. Shortly after on a ride it emptied the contents of the oil tank onto the road via the crankcase breather behind the clutch. After help form the forum ive replaced the cork washer in the times breather and fitted a SRM oil pump incase it wasnt getting sufficient return. Ive still the same issue but it will also throw oil through a breather behind the barrels too.

I’ve checked the scavenger pipe ball which is clear but i noticed that the scavenger pipe doesnt line up with the hole in the gauze filter and has damaged it as a result. I’ve bought a new SRM gauze filter but the scavenger pipe is still out of line.

Would it this misalignment prevent proper scavenging of oil in the crank cases and if so how do I adjust/move the pipe?  I can’t find any images on the internet.

Also, even though the engine runs cleanly, could the crank cases breather be mistimed or is that not possible?

Ive read the ‘dazed confused and covered in oil’ thread bit im at my whits end.

Thanks in advance

[Triton Thrasher]

Watch out for aftermarket sump plates with magnets in drain plugs too close to the steel ball in the scavenge pipe.

[Flash Chris]

Interesting. I’ve just bought a sump plate with magnetic drain plug thinking it might help scavenge errant bits of swarf circulating around a newly rebuilt engine. But it might cause more problems?

[chaterlea25]

Hi All,

Watch out for aftermarket sump plates with magnets in drain plugs too close to the steel ball in the scavenge pipe.

Oi TT thats my line, 
 
Harvey,
  There is only one breather outlet on the engine pointing down towards the gearbox sprocket.
Get a deep socket or strong closed fitting tube that will fit over the oil pickup tube and "manipulate" it so it will poke through the screen.
Make sure the ball is free afterwards, and also it is held from going  too far upwards by the cross fitted pin.
Check that the pickup pipe is not magnetised !!
If the sump plate has a magnet, fit the plate so the magnet is furthest from the pickup pipe

When Its back together, remove the return pipe from the oil tank and point it into a container,
Start the engine to see if return oil is being pumped into the container
If it does not, undo the return at the crankcase and repeat,
If oil is being pumped through the return line, reconnect to the tank, repeat start and observe
If not then the oiltank return stand pipe is restricted or blocked!
Have you made sure the oil tank has been cleaned.
Is the tank vent clear?

If the engine needed a "thicker" cork washer its possible that the drive peg has not been engaged with the
rotating "top hat" so breathing is restricted 
With the outer timing cover removed, grip the rotating breather, it should "rock" a little on the drive peg, stiff with finger pressure but easy using a pointy pliers..
Next, arrange some rubber tube or similar thats a tight fit into the hole in the top hat, As you rotate the engine you should be able to blow through the breather once per crank rotation, (twice per cam- breather rotation)


John

[Harvey_Mushman]

John, thanks do much for the pointers. Ill have a go at your suggestions and let you know how i get on. Thank you.

[Swarfcut]

 Not wishing to tempt fate......

 Looks like the problem is a poor oil return, and yes the pick up pipe and gauze filter are  critical, being the first stage of the scavenge system. So any obstruction  to that ball valve and even the wrong mesh size of the gauze filter can be the root cause. The pipe intake should end up near the base of the stump plate, immersed in oil that has filtered down through the gauze. Later models have a plain sump plate and a flat gauze. The pipe is lower than the crankase mouth, and can get bent upwards if mishandled by being placed on a flat surface without the sump plate in place.

   It is worth  also checking the oil lines are clear and connected correctly. The crankcase is stamped F for flow and R for the return. I'm sure all is in order, but worth a look. CJ's test is a simple check.

  On S/A engines the pick up pipe can be removed from the crankcase with a bit of heat, reseal with Loctite. Any air leak at this joint will result in poor oil return, pulling air not oil. But the oil return will be good on a wet sumped engine until the level drops below a leaky joint.... A fault that has puzzled many. Sadly the Plunger crankcases have to be split for any attention to the pick up pipe.

 Swarfy.

[RDfella]

Has the sump plate been fitted with a magnetic drain plug? Just a chance a powerful magnet could hold the return ball closed.

[Harvey_Mushman]

Hello, im not sure if the old sump was magnetised but ive bought a new alloy one with a magnetic plug so ill check that ots not interfering with the bearing in the scavenger pipe. Thank you.

[MissingU]

Worth checking if the ball bearing in the pickup pipe has become magnetised. It would lead to erratic operation. Sometimes working Sometimes not. Thank you Pete