I have been aware for a good number of years that the banjo oil feed thread into the oil pump was weak, so I fitted a modified banjo with drain nut and never had a problem, until that is I took my bike to Francois Grosset to have an electric start fitted, as Francois unscrewed the banjo little bits of aluminium tread came with it, nothing to do with Francois you understand, it was something waiting to happen, I carefully ran a tap into the thread or what was left of it and then a bit more, and finished off with a plug tap, then took great care in removing all visible swarf, but I am not happy, I would like a strong permanent repair, but is this in anyway possible without an engine out job and splitting the crankcases, my bike runs so well at the moment I would rather not have to disturb it all, any solutions for me anyone?
ET: Engine (Twin) Repair or Solutions
- Thread starter Peter Holmes
- Start date
I had this the day I bought my first Vin, 1965, As I got home, looked down, Oil all over the place.
Ron ran a tap the next size up, And welded up a converter so I could still use the standard banjo bolt, It means the pipe is 1" or so further away from the engine.
And it's still on there !!. Cheers Bill.
Ron ran a tap the next size up, And welded up a converter so I could still use the standard banjo bolt, It means the pipe is 1" or so further away from the engine.
And it's still on there !!. Cheers Bill.
H
see Paul richardsons book Vincent mototcycles page 39 for repairs to the oil pump main feed banjo bolt thread (stripped thread).
stumpy lord
Helicoil / thread insert, two things to be careful of; A. make a guide so that the tap goes in dickenpurpular and B, specify "3x" inserts as, being "nominally" 1/4" B.S.P. they usually supply "1.5x" inserts with the kit which are only 3/8" long! B.S.P. thread is something like .519" o.d. if I recall correctly, so the "3x" inserts go 3/4" deep. If that is too deep, shorten a little with a Dremel before using. A useful guide could be a piece of alloy tube that has an accurately turned off face abutting the joint face of the banjo fitting, with a hole that just allows the tap through. Grease on the tap and doing the job upwards should minimize swarf contamination and maybe break off the fitting tang of the insert with pointy pliers to capture it. You folks who read less poetry have probably got better solutions.
The thread is not overly deep, and it is offset to the center line of the pump bore. An insert would be better than a helicoil, it is a tricky one. Perhaps Trevor can assist with some sound engineering advice. It is possible to do without an engine strip, but it is difficult to keep everything "square and true" using hand tools. Good luck.
sorry wrong page, should have been page 55
Whatever way you choose to repair you have to move metal. You shouldn`t have a problem if you fill the tap with grease, take a couple of turns, remove, clean and replace grease. do that a few times `til you`ve reached the depth required, you`ll find that works.