This sounds like a very good and workable solution. I like the visual appeal of copper, so I can make spacers from copper instead of aluminum.
Copper Inspection Cap washers (ET160)
- Thread starter Dynamiteboss
- Start date
I do not think you will be relying on the rubber o-rings to secure your valuable valve caps, if you do you won't have them for very long, oil lubricates rubber very well, and makes it really nice and slippery, perfect for losing your valve caps, but nipped up onto your aluminium spacer that is retaining the squeezed o-ring, that will retain your caps.
You could try with o-rings alone, the oil gets squeezed out on assembly and not much remains. Remember the pushrod shrouds and their rubber seals, a pain to remove after some time. At this place I did my o-ring adapters in the engine case, no benefit of having square types in the recesses. But this is another topic . . .
Vic
Vic
My 1964 Honda CB77 uses o-rings incorporated into the valve caps, let into a grooved recess, but still relies on metal to metal contact when the valve cap is tightened, I think some Vincent owners have tried modifying the valve caps in a similar fashion, but I would be concerned about lowering the desired position of the valve cap.
The standard lower pushrod tube seals are not o-rings, and you do not rely on them to retain any exterior engine parts, they only retain oil, or attempt to, but on occasions they can creep out of their crankcase recesses.
Peter, I was just trying to show that rubber seals CAN produce a lot of friction when wanting to move anything like pushrod shrouds. Vincenteers like to push them down when lifting heads from cylinders - and then you have to add extra lube for lowering them. One reason why I selected o-rings down there. Certainly with o-rings on inspection covers I have the alu spacers around them for preventing them squeezing out, temperature is on the limit for NBR rings, Viton is safer in case of troubles, but don´t think so. At least no need for decent torque for securing the caps when an o-ring is used, quite unlike copper seals !
Many decades ago when on the way to Switzerland and a British bike meeting one of our bunch of riders had a 250 Triumph I think - and no shit - he lost one valve inspection cover on the road from vibes. Think he never found it and had to do some bodge for keeping oil inside. My guess there was no o-ring involved, rather a harder type of seal . . . .
Vic
Many decades ago when on the way to Switzerland and a British bike meeting one of our bunch of riders had a 250 Triumph I think - and no shit - he lost one valve inspection cover on the road from vibes. Think he never found it and had to do some bodge for keeping oil inside. My guess there was no o-ring involved, rather a harder type of seal . . . .
Vic
My Comet came to me with the faces of the valve caps turned with a shallow radius and O rings fitted, about 3mm section. There is no way the O rings could crush enough to give a metal to metal contact, but the caps appeared to stayed put in use just with the friction created by the rubber.
Funny when you see attempts at grooves made for "O" rings and just turn a half or slightly more deep round groove into alloy or similar.......no where for the O ring to go........has to be a square or similar recess with some extra room for the rubber to squeeze into.
Nearly all car oil filters use an o ring, usually square cross section. They don't fall off and only need to be tightened by hand.