oil pump leaking ??

[Johnwebley]

I have a CB500-4,

 1974 M plate,

 recently its been dripping oil,and when I removed the gearbox sprocket cover,I noticed the section that covers
the oil pump,was lots of loose oil about,

 I had a look around,its very clean,no obvious leak,
 looking in the manual,I see a large O ring,and several smaller O rings at the mounting bolts,also the pressure-relief
cap,

any ideas?

[Bryanj]

Its normally the outer cover  "O" ring which is not in the parts list but a 46 x 2 O ring fits, you can order it from Honda as a Goldwing part and the number is posted on here somewhere

[matthewmosse]

I have had a couple leak from the oil pressure switch over the years.

[totty]

There a few seals under that cover that could leak oil, it would make sense to clean it and see where it leaks when you next run it. My money is on the gear selector shaft seal.

[Johnwebley]

There a few seals under that cover that could leak oil, it would make sense to clean it and see where it leaks when you next run it. My money is on the gear selector shaft seal.

  the oil only collects in the pump section,I will ask my local guys if they have loose seals,if not,I guess
its try and find the Honda ones,

if I remove the pump,I will need

 2x 14 X ? on the mounting screws,
 1 x 47 x 2 pump to crankcase joint
 1 x 46 x 2 for end cover,
and maybe the 19 x 2 pressure relief cap

I have looked online for oil rings,seems if you know the size,
they can be had,very reasonably as well,
btw,what do think the max temperature around the pump ?

thanks all

[florence]

when this happened to mine it was the oil pressure switch.  If you start the engine with the sprocket cover off you may see oil coming from the top of the switch.

[Johnwebley]

took the outer casing off,

 cleaned all around the pump and housing,

started the motor a looked,using a mirror to check underneath,

the end plate weeped a little,but the main leak seemed to be from the high pressure feed to the motor,that dripped quite a lot,
so,easy I thought,get my impact driver,remove all the screws,and the pump,fit new "O" rings,NP !!

WRONG !! those damn screws are so tight,I only managed to loosen one,
not wishing to risk damaging the heads,I decided to replace everything,and consult my local bike engineer,
gave him a list of O rings needed,and will get him to strip it down,