Little puffs of smoke

[simon.holyfield]

Today son Thomas and I had a jolly day out with the local VMCC section, him on the SQ4 and me on his Interceptor for a change.

I now know that the SQ4 puffs a bit of smoke, a tiny bit, when you crack the throttle open and when you shut off. It's not enough to worry about, but it's probably worse on the timing side.

I have a feeling there was a post about this a while ago.

It's had new rings, valves and guides in the last 3000 miles and is bog standard apart from the Morgo.

[JohnnyBeckett]

hi i think it is a little bit of oil going down the valve guides

[simon.holyfield]

hi i think it is a little bit of oil going down the valve guides

Me too. No seals, flat topped guides, inevitable really.

[Chris Sealy]

I put Teflon washers on my Mk1's inlet valve stems, to act as little umbrellas. So far, no smoke from the exhaust; but then it has done only 200 miles since fitting them. So I may be celebrating too soon.
Cheers Chris.

[simon.holyfield]

I put Teflon washers on my Mk1's inlet valve stems, to act as little umbrellas. So far, no smoke from the exhaust; but then it has done only 200 miles since fitting them. So I may be celebrating too soon.
Cheers Chris.

Good thought though. We're they tight on the stems?

[Chris Sealy]

Yes, they are tight. They sit at the very top of the inlet valve stems, as most of the valve stem disappears down inside the guide at full lift. I bought undersize {metric} Teflon washers and trimmed the inside diameter to a chamfer, using a sharp knife.I then shaped them on a tapered stick. I believe that the main route, that the oil takes onto the valve stem, apart from mist, is via the gap between the collets; therefore there is room for experimentation here, with a modern high temperature silicone sealant. I may try this at a later date, if my little umbrellas fail for any reason.

[paul.jameson]

The late Bob Brassington used to assemble his collets with high temperature silicone for this reason.