triumph trophy oil problem

[dunboyneroadracing]

i have been having a heck of a time with a newly bought 1965 triumph trophy 650 and am looking for advice.
the oil is pumping from the tank to the engine fine but not returning back , the result is that thesump is filling and its leading to clouds of blue smoke from the exausts and the head gasket is starting to weep, theover flow in the centre underneath of the engine is letting a lot of oil out too. i checked external oil lines,inspected the oil pump/cleaned it completely (including the little ball bearings ) and dont know where to look next.
anyone expierianced this type of problem before?.
the bike had been unused for a fewmonths, i have drained the sump several times .
thanks in advance
anthony

[33d6]

I've only ever experienced this problem with  Ariel singles. They use  the same type of oil pump set up. In my case it was always a speck of dirt under the seat of the return pump but there is more to this than meets the eye.
1 As well as cleaning the return ball tap it gently on to its seat to ensure a good fit.
2 Make sure the pump body is a good fit on the aluminium face of the crankcase. If necessary reface it by gently rubbing it down on a flat piece of glass.
3 Replace the gasket between the pump and crankcase. Ariel used to recommend adding a very thin .005 paper washer around the return area to ensure it was a little tighter there. Also ensure the drive block isn't stopping the pump snugging home flat.
4 If the above doesn't work and the pump itself is in good nick, it is time to suspect an air leak in the pipe between the sump and the pump. Very rarely the internal oil scavenge pipe between the sump and the pump will develop a leak. If it has, it usually means a complete strip down to get to it. The repair is simple but a monumental pain to get to.
Finally of course, there is the obvious. Is the oil return pipe blocked so the pump can't return anything anyway?  I have seen replacement oil pipes made out of the wrong material that rots and swells internally to block up pipes yet it still looks good externally.
Who knows what has been done to your bike in the last 40 years?
Hope this helps, best of luck, Bob

[TBS]

"the bike had been unused for a few months"
Was the oil returning to the tank before you laid it up?

 Anyway, I would check the oil pipes. On looking from the right side of the machine, the front pipe (lower and slightly forward) is the feed, the rear pipe (higher and slightly further back) is the return. If these are fitted the wrong way round, then the sump will fill very quickly as the scavenge pump is twice the size of the feed.

[pogotri500]

Hi Anthony, We had excactly the same problem with my mates 72 Bonnie it did our heads in for weeks. We checked , replaced, stripped down and rebuilt, just what has already been put forward. Eventually in desperation we took the pressure releif valve apart and there it was the previous owner in his wisdom had shortened the spring! Said spring was replaced with spring of correct length - no more problem! It may be worth a look. Cheers, Dave.  

[dunboyneroadracing]

many thanks for the replys .
i cleaned the pressure releif valve and the pump (yet again) ,this time i pre oiled the pump before replacing it , after a few minutes of running the oil started flowing ,
 
then it was off for a spin , untill i found out that i had replaced the gear selector with the selector plate in the wrong position and thus could only get 1 gear   .
all sorted now though .