Stupps

Some really useful info in those links, thanks gents. That G&S manual is very interesting, a lot of it over my head but I'll save it for future reference. Was particularly interested to read that weak valve springs could contribute to stem breakage like mine, due to valve float. Not something I'd thought of. I've ordered some NOS Tranco exhaust valves off eBay to use in the rebuild. Not that I necessarily think they'll be better, but I'll have some peace of mind that I've done something to avoid repeating the same failure. Will stick with the modern inlets. I now feel a lot better informed about valves! Nothing is ever straightforward is it... Thanks very much for all the info. Pete

Thanks very much for your insight Roger, most appreciated, your last paragraph sums up why I'm worried about all the other valves! Seeing it in the flesh I thought that lump at 3 o'clock might be a ridge next to an indentation left by post-break impact from the flying valve crown; but in any case I take your main point that it failed abruptly at the join. I'll have a play with a magnet just to see if there is a clear difference between head and stem materials. Tony thanks for that link - I might well give them a go, they've got the right part number. Do we think those old Tranco valves would be alright with unleaded? I'm not sure if the newer valves are harder, or they're just labelled as 'unleaded' to draw money out of fools like me.

Thanks for the feedback everyone, Colin I'm glad to hear it isn't totally unheard of. I'll certainly change the conrod, it's a bit mashed. I'll speak to Paddocks today just to pass on the info, can't imagine they'll accept responsibility and it was probably 3 years ago that I actually ordered the valves. I will ask about who makes them though - don't recall seeing any manufacturer's details anywhere. The big question is how I treat the other valves from the same batch, and then the ones I ordered 2 years later which are a different batch (different size and collet type). Am inclined to ditch the other 3 exhaust valves, and possibly refit the old original ones as they weren't in bad shape. Spent quite a while trying to get a photo of the broken end in focus, below is the best I managed. Roger apologies it's not square on! Lighting for photography is tricky in the garage and I could do with a nice macro lens... Not sure how much of that damage was done after the head had broken off, there was evidently a lot of metal flying around for half a minute. To be honest I don't know, but think these are two-piece valves. Is there any easy way I can check with one of the undamaged ones? Here's a pic next to an unused inlet valve (from a different set but also from James Paddocks) and the break is aligned exactly with the apparent change in materials.

Hello all, Infrequent contributor to this forum but thought I'd share some pictures of a depressing piston destruction event (sorry to Sideways regulars about cross-posting). I bought a 1300fwd a few years ago, then spent two long years slowly rebuilding the engine. Fully back on the road since April, it had given me various niggling problems but after 1800 miles I thought I was just turning the corner and could trust the bloody thing. Then on Boxing day, 15 miles after checking the plugs and valve clearances (everything appeared healthy) I was bowling along a country lane when there was a loud clackety-clack, loss of power, and I limped to a halt outside a pub. Took the plugs out and could see from no.4 that I had a major issue: Got the head off yesterday, and surveyed the damage. It turns out that the exhaust valve had broken, and whatever is left of the valve head must be sitting in the sump. Hopefully it didn't do any major damage to the crank on the way down. Can't drop the sump pan on these cars so I'll have to pull the engine out to fully assess the situation. Here's what was left of the valve stem And here's that damaged plug next to no.1 plug. It looks a shade lean, but I wouldn't have thought too bad. The question is: how to I make sure this doesn't happen again?! The valves were standard items from James Paddock, and I have another batch from the same place to go into my Spitfire head. I'm a bit hesitant now though. Presumably it was a manufacturing flaw, although I wonder if the engine was running a bit hot and if that might have contributed. Anyway hopefully it won't take me another 2 years to get it back into service. Cheers, Pete

My up-and-over door is a good 10 inches clear above my spit bonnet when raised, so don't rule them out!

Apologies if I'm saying things that aren't news to you, by the way.

You're not really supposed to polish chrome! Abrasive polishes e.g. Autosol, restore shine by shaving the surface of the metal off. When you consider that chrome is barely a micron thick or something, you haven't got much to polish off before you're back to the steel substrate. Which is exactly what I did to a (previously) nice chrome motorbike petrol tank when I was a youth. However, when the chrome is already pitted and the rust from the steel below is coming through, polishing the rust away does make it look better. But the pits and roughness of the steel will stay there, and you'll end up with more because you've taken more chrome off. The advice I read was to paint or waxoyl the underside of chromework, then wax and buff the visible area. Whenever the chrome gets wet make sure you dry it off and re-apply wax occasionally. Incidentally my bumpers are in a much sorrier state than yours, and I'm thinking about saving for stainless repro's. Pete

Haven't dealt with them but I came across this site when googling Ashley hardtops: http://www.ashleygt.co.uk/ They might be able to assist, as they appear to be fabricating tops (and other panels).

Thanks Pete. I was surprised by it myself but the nut is not going back into the threaded tube. I've now got tank out on the bench and the nut detached from the pipe but still no joy. The damage will have been done when I tried, in error, to screw the tube itself off (it's hexagonal, I thought it might be easily removed from the tank). Will try re-tapping the thread inside the tube and see how it goes.

Hello all, new member here so please be patient! I removed the compression joint from my fuel line at the tank, to take the fuel tank out. On attempting to reassemble I couldn't then get the brass nut into the threaded drain plug (if that's the right name for it) to remake the compression joint. It seems i've ovalled the drain plug in a foolish attempt at removing it. What do I do now?? Is it possible to replace the drain plug? I wondered if it could be re-tapped but not sure that would work. Any suggestions gratefully received. Pete