Push rod tube oil leaks

[John Cone]

I think i have found a solution to leaky push rod tubes at the top without having to disturb them. Undo the nut and let it drop down, towards the top of the tube carefully wrap around the tube clockwise 8/10 times some PTFE tape then gradually push it up into the orifice using the nut and tighten. It seems to have cured my drip on the rear inlet tube. Only time will tell.

 

[Alan J]

It's the bottom end that has caused me problems in the past!-any tips there?

 

[vibrac]

If its a D then its well known the holes are too big

 

[Paul Ennis]

Hi Alan,
I've cured lower seal oil leaks by prising them out and sliding them up the pushrod tube, cleaning out the recess using white spirits on a cotton bud, squidging some silicon adhesive sealant in the recess and pushing the seal back in place.
It's quicker than removing the heads!
Paul.

 

[John Cone]

Having been prewarned that "D" were a problem, when i did my overhaul many years ago I cleaned out the seal holes with meths and stuck the seals in using ordinary superglue. The only time it's shown a weep between the tube and seal was when the elephants trunk breather got gunged up with condensation sludge but it's been alright since.

 

[Alan J]

Thanks, chaps!-I know of course that the leaks are often caused by excessive crankcase pressure-piston blowby e.t.c. It seems a lot of old Brit. bikes pressure release valves are too small-including Vincents! My 500 A.J.S. breathes thru' the end of the crankshaft and if "stuck" it blows oil out round the dynamo!

 

[Marcus Bowden]

Fit Ex Works Grey Flash push rod assemblies ! ? You may ask. The seals can be renewed with out removing the heads and when stripping down the hassel of with-drawing the pushrod tubes out of the heads no longer applies ( usually get marked up dew to the pliers or mole grips when trying to get them down) as the adaptors that screw into the head are funnel shaped and fit into a mating funnel at the push rod tube and is all simply sealed by an "O" ring on the adaptor, there is of cause a stag when doing the "rear EX" & " front IN" as the tank has to be removed to extract the push rods.
The sequence is to remove the pushrod, unscrew tube nut,,, push tube down through the seal,,, unscrew adaptor out of head ,,,remove tube & tube nut,,, extract old seal,,, fit new with what ever extra goop you wish and reassemble..Have made several sets for various folk who like the idea but it is time consuming.

 

[greg burt]

Try Sycaflex in place of the bottom seals
Greg

 

[vibrac]

Sycaflex 221?