Post by rolie on Oct 17, 2022 15:29:22 GMT 1
I’ve finally managed to gather together all the bits for my leakdown test kit. 🙂 The test showed a leak at the balance tube junction on both reed valve rubbers. 🙁 New clips had already been fitted.
On close inspection the rubber still looks ok, it’s fairly flexible (it was soaked it in a solution of oil of wintergreen and isopropyl alcohol) and there’s no obvious cracking or crazing around the upstands where the clips go. That said, it leaks at 5psi so it obviously isn’t doing its job properly.
While I have fitted new spring clips, presumably a better seal could be achieved using a something that could be tightened, like a small jubilee clip or hose clamp. Any thoughts!
I also have a query about the pipe itself. The bends are not quite 90 degrees meaning that the two sides are not parallel. Is this right as I assume the rubber inlets are not angled, otherwise there would have to be different part numbers for the left and right sides? I’ve looked at a number of photographs online and they do seem to be slightly splayed on the 4L0/4L1 but square on the YPVS. Perhaps the mounts on the barrels are slightly canted inwards.
The best thing is no doubt to stop mucking about and just replace both rubbers but there’s a credit squeeze on. Norbo has genuine replacements so that’s probably where I’ll end up but it’s annoying as it shouldn’t be that difficult to make a good seal between a rubber boot and an aluminium tube!
Rolie
On close inspection the rubber still looks ok, it’s fairly flexible (it was soaked it in a solution of oil of wintergreen and isopropyl alcohol) and there’s no obvious cracking or crazing around the upstands where the clips go. That said, it leaks at 5psi so it obviously isn’t doing its job properly.
While I have fitted new spring clips, presumably a better seal could be achieved using a something that could be tightened, like a small jubilee clip or hose clamp. Any thoughts!
I also have a query about the pipe itself. The bends are not quite 90 degrees meaning that the two sides are not parallel. Is this right as I assume the rubber inlets are not angled, otherwise there would have to be different part numbers for the left and right sides? I’ve looked at a number of photographs online and they do seem to be slightly splayed on the 4L0/4L1 but square on the YPVS. Perhaps the mounts on the barrels are slightly canted inwards.
The best thing is no doubt to stop mucking about and just replace both rubbers but there’s a credit squeeze on. Norbo has genuine replacements so that’s probably where I’ll end up but it’s annoying as it shouldn’t be that difficult to make a good seal between a rubber boot and an aluminium tube!
Rolie
will make a difference on what is a critical area, and quite often a culprit for air leaks.
