classic motorcycle forum

Could it be the backlash in the cam gears when the torque on the cam is reversed as the follower goes over the peak ? This would be more noticeable when turning slowly.

The current thinking is that its something along those lines.

What's got me confused is that the guy who has done 100s of these engines has not experienced this noise before. If it was something expected like that backlash you'd think he'd have seen it at some point in his career.

Find Your Type Tonight - No Selfie
https://PrivateDates.live
 
One Night. No Regrets. Just Pleasure.

More tinkering today....

I'm still trying to figure out where this clacking noise is coming from, and after a bit of fiddling about, it occurred to me to try rotating the engine within the timing cover off again.  I was trying to figure out if there was a worn interaction in one of the ball joints (either end of the pushrods).

With the timing cover OFF, the clickety clack is NOT there.  Whatever is causing this is only in effect when the Timing chest cover is fitted.

So - I continued trying to figure out what could possibly be happening.

I dug out a 1/2" length of rod so I could assemble the timing components in the cover, rather than the cases (to see if anything was interfereing)

First the rod needed a tad of tidying up. (No idea what it was originally)


It just needed to allow the cam-followers onto it, so rough was good enough.

I can confirm that there's nothing interfering due to the timing cover.



So - with more investigation... we get more information.

And here's a video explaining what I believe i have discovered.
https://youtu.be/HmQjgWlt1uA

So my choices are:
Order a new pair of bushes and in the meantime, strip the entire thing down again, with no guarantee (despite what I believe) that this is a solid fix;
Or:
Accept this slight looseness and carry on, knowing I'll need to strip the engine again at some point soon(ish) and accepting that there'll be a tad more wear happening in the current bushes. I don't know what that movement will do to the rest of the components: ie. what extra wear (above the usual) would be caused by carrying on.

Difficult decision. (I'm currently waiting to see if I can get a chat with the Guru to se what his opinion would be). Stripping the entire engine down would be somewhat demoralising at this point, even though I now know how simple it actually is.  It's more the faff of stripping and cleaning the sealants and re-making gaskets etc that puts me off.

I reckon your vice is as collectable as your bike will be.
What is the intended rolling chassis?

So, back in the sauna, err, sorry, shed.

I took a look at the Pilgrim Pump banjo unit first, to confirm what is going on with the oil feeds.
This is the feed pipe top banjo fitting:

and the bottom end:


As you can see, neither have a "channel" inside the fitting, so my thoughts are that for decent oil feed, both "male" fittings really should have a channel.

This is the outlet from the Pilgrim pump:


No channel.
So - I figured I could swap to the new banjo post I received inadvertently.


....


Have you ever known anything on this project to be that simple??



....


This is the new banjo post flapping around loose in the Pilgrim pump.


Here they are back to back.


the NEW fitting is 1/8" BSP 20tpi.
the diameter fraction is "internal".... Edwardians!
the outer diameter of the threads is 0.378, (nominally 0.383 according to Zeus)

the OLD fitting is 1/4" BSP 19tpi (wtf?? BSP is weird),
the outer diameter is 0.510 (nominally 0.518, Zeus says)

So - the fitted Pilgrim pump is a weirdo too! ffs.

Luckily I don't need to chase down yet another sodding banjo post, because the old one on the pump is fine.
The new 1/8"BSP banjo will be thrown into the box of useless bits.

I dug out a couple of copper washers for the Pilgrim pump banjo, have I mentioned in the past my opinion of felt washers...





Next job was to try the timing box with some oil in.


Dribbling some oil on the cam(s).


Fitted up with the new pushrods (I tidied up the excess epoxy a bit too, but there wasn't a lot).



STILL clickety clack. 

ffs.

So I took some time to have a damned good look at the timing chest mechanisms, and I still can't really see anything wrong at all.

The inlet follower DOES get VERY close to the casing when the cam is "off", and I was wondering if this very very slight mark was an indicator of that...


There's a possibly corresponding "nick" on the very edge of the boss that holds the camshaft in the casing :
(right in the centre of the image)


So, I took the follower I've designated as the "inlet" and shaved off a tad of a chamfer on the lugs:






I also took a sharp knife and shaved off a tad of a chamfer on the boss in the cases:


Close up:


There's now a significantly bigger gap when the follower is on the lower part of the cam.


Did it make a difference I hear you ask??



...


did it buggery. :roll:

So I carried on with the aim of making the notches in the followers to allow better oil flow to the moving parts.


Advice from the guru was to do both, but make sure they are on "different" sides so they aren't going to interfere with each other.


I'm nigh on giving up on trying to solve this damned "click-clak" sound.  It ONLY happens when the pushrods are in place and under compression from the valve-springs.  Remove that compression and the timing chest is utterly silent when it rotates.