Hitchcocks Forum

Your thoughts on this please gentlemen. A friend has a 2005 350 Bullet. Following a pump spindle failure and thence a bigend failure my friend had an extremely poor engine rebuild in Norfolk where he was visiting. He made it back to the Isle of Man. The bike has run for a few hundred miles since the rebuild, albeit leaking profusely. In the last couple of days the bike has taken to blowing scavenge side oil pump gaskets. A new gasket is lasting only minutes. Loosening the rocker banjos reveals an oil flow in the usual manner. There seems to be a build up of pressure as oil is squirting from the oil pump gasket. I was thinking maybe a blockage in the rocker blocks but would have expected, in that case, that there would be a high pressure squirt when the banjoes were loosened. He is using Morris 20/50. Any ideas are gratefully received.

Hi EDWARD----- have you actually removed the rocker blocks completely and thoroughly cleaned and checked for white metal remnants ?? As with any pump they will only make a pressure against a "restriction"-- otherwise it is only a fluid-flow. When you slacken off those banjos you have removed any form of restriction, beit normal oilways OR blocked oilways,---so the pump will just give a fast flow at a low pressure----My guess is you will find a blockage in one or both of those rockers.

Edward,
Whitemetal is stuck in the rocker blocks, the oilways are blocked.

------ I meant to say, as an example---a garden hose pipe with water flowing out slowly---put your thumb on the end and BINGO !!---suddenly there's your pressure being formed. Same thing with your oilways.

-Oh, hello NORM--hows your 2-o-clock testing these days ?? The re-build wasn't done properly I think. Sounds like there are still some flakes of white metal being flushed out from somewhere.

Thank you Alan and Norm for your kind replies. I will inspect the rocker blocks.

Edward, inspect them very carefully because unless you know what you are looking for it is hard to spot. The top blocks are the ones that will be full and the slots have to be cleaned out. The reason it blows the gasket is there is no pressure relief in the scavenge line and the whitemetal gets caught in the rockers so consider yourself lucky that it is blowing the gasket because it often strips the pump spindle as well. Might pay to check the spindle as well while you are at it

I had a look today at my friends rocker blocks.Just as advised by Alan and Norm, the rocker block grooves were blocked solid with white metal.