Jonny-Jimbo Posted January 7, 2016 Share Posted January 7, 2016 Morning all,I was looking at one of my spare engines the other day and I noticed that when the PO was trying to remove the front pulley they broke the rim on it where the belt runs. I assume they were using a three legged pulled on it.Anyway, I was wondering, does anyone do aluminium ones? I'm planning on rebuilding the engine as a 'go faster' one, but not a 'race' engine. Figured as it needs changing anyway, I may as well put an aluminium one on if they're available.If not, would anyone be interested if I arranged production of them? Quote Link to comment Share on other sites More sharing options...
BiTurbo228 Posted January 7, 2016 Share Posted January 7, 2016 I haven't seen them around before, but I would be interested if the price is reasonable Quote Link to comment Share on other sites More sharing options...
uksnatcher Posted January 7, 2016 Share Posted January 7, 2016 What engine?Spit 1500 here £75http://www.jigsawracingservices.co.uk/engines.htm100 217789A Crank pulley, alloy, Spitfire 1500 1 75.00 Quote Link to comment Share on other sites More sharing options...
BiTurbo228 Posted January 7, 2016 Share Posted January 7, 2016 Quoted from uksnatcher What engine?Spit 1500 here £75http://www.jigsawracingservices.co.uk/engines.htm100 217789A Crank pulley, alloy, Spitfire 1500 1 75.00 Ah good point, mine's a 6-cyl... Quote Link to comment Share on other sites More sharing options...
uksnatcher Posted January 7, 2016 Share Posted January 7, 2016 The search for 'rocking horse poo' shall continue for you then... 😉 Quote Link to comment Share on other sites More sharing options...
BiTurbo228 Posted January 7, 2016 Share Posted January 7, 2016 Quoted from uksnatcher The search for 'rocking horse poo' shall continue for you then... 😉 I wonder what the differences are... Quote Link to comment Share on other sites More sharing options...
Jonny-Jimbo Posted January 7, 2016 Author Share Posted January 7, 2016 Hmm, I calculate at least 5 different front pulleys... Which ones are worth doing?4 pot small crank4 pot big crankVitesse / GT6 typeMk3 GT6 type2.5L TR6 etc Type... Quote Link to comment Share on other sites More sharing options...
Jonny-Jimbo Posted January 7, 2016 Author Share Posted January 7, 2016 It's a Mk3 spit engine, so small crank.One of my mates runs a machine shop, so if I buy material he often does small runs for me without charging too much for the labour.Might look into it if I can get example of all the front pulleys. Quote Link to comment Share on other sites More sharing options...
BiTurbo228 Posted January 7, 2016 Share Posted January 7, 2016 Quoted from Jonny-Jimbo It's a Mk3 spit engine, so small crank.One of my mates runs a machine shop, so if I buy material he often does small runs for me without charging too much for the labour.Might look into it if I can get example of all the front pulleys. Which particular bit are you thinking of making? If it's the pulley/damper then on the long-stroke engines it's actually useful to have a bit of weight there as it damps vibrations... Quote Link to comment Share on other sites More sharing options...
Jonny-Jimbo Posted January 7, 2016 Author Share Posted January 7, 2016 Hmm, that's true actually, on the bigger engines they are 'dampers' not just pulleys...Still, might have a look at doing 4 pot ones. Quote Link to comment Share on other sites More sharing options...
That Man Posted January 7, 2016 Share Posted January 7, 2016 Don't forget the front seal runs on the pulley, so aluminium here may wear quickly? Maybe you could use one of those repair sleeves where the seal runs.For my 1300 fwd I made a titanium hub which takes a aluminium drive pulley. Just the hub and pulley weigh 520grm plus a bit for nuts and bolts.It's probably a bit OTT but it's what I do 😉 Quote Link to comment Share on other sites More sharing options...
ferny Posted January 8, 2016 Share Posted January 8, 2016 Quoted from Jonny-Jimbo Hmm, that's true actually, on the bigger engines they are 'dampers' not just pulleys...Still, might have a look at doing 4 pot ones. Sell them as a set of three? Second to replace the first when the keyway wears and the third to put on as you look for an original replacement when the second has had it? Quote Link to comment Share on other sites More sharing options...
Slimboyfat Posted January 8, 2016 Share Posted January 8, 2016 Quoted from Jonny-Jimbo Still, might have a look at doing 4 pot ones. Really? On a three bearing crank?Triumph added weight to the steel pulley on the race engines. Quote Link to comment Share on other sites More sharing options...
BiTurbo228 Posted January 8, 2016 Share Posted January 8, 2016 Hmmm, perhaps a better thing to do to save weight (overall rather than much rotational) would be to replace the cast iron block that clamps the pulley into place with an alloy one.Would be fairly easy to machine up if you have a lathe as well... Quote Link to comment Share on other sites More sharing options...
thescrapman Posted January 8, 2016 Share Posted January 8, 2016 Quoted from Slimboyfat Really? On a three bearing crank?Triumph added weight to the steel pulley on the race engines. DaveI don't think he said how big he was intending to make them..... I wonder if it would be beneficial to have the front pulley weighing the same as the flywheel??You could radically lighten the flywheel and still have the same rotating mass that way. My basic physics says it would also be better balanced, less harmonics perhaps.Call in an expert!!! Quote Link to comment Share on other sites More sharing options...
JohnD Posted January 8, 2016 Share Posted January 8, 2016 Quoted from That Man Don't forget the front seal runs on the pulley, so aluminium here may wear quickly? Maybe you could use one of those repair sleeves where the seal runs.For my 1300 fwd I made a titanium hub which takes a aluminium drive pulley. Just the hub and pulley weigh 520grm plus a bit for nuts and bolts.It's probably a bit OTT but it's what I do 😉 Why on Earth have you made a flywheel cum crank pulley?How do you get the belt from there to the water pump and alternator?But the problem is indeed harmonics, which would be worse with a heavy flywheel on each end of the crank.Four cylinders are short enough to get away without, but not sixes. They need that damper in the crank pulley, and how well they are working after a minimum of forty years' use is anyone's guess.I'm grappling with Holtzer calculations at present to work out the frequencies in Triumph cranks - anyone an expert?John Quote Link to comment Share on other sites More sharing options...
thescrapman Posted January 9, 2016 Share Posted January 9, 2016 Quoted from JohnD Why on Earth have you made a flywheel cum crank pulley? Because he has a 1300FWD... That bit that looks like a refugee from a washing machine is the starter ring gear. Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted January 9, 2016 Share Posted January 9, 2016 Quoted from thescrapman That bit that looks like a refugee from a washing machine is the starter ring gear. That comparison is spot-on 😀 The starter usually makes a gruesome noise too, especially when the rubber bushes (!!) between ring gear cage and pulley get tired.Nick Quote Link to comment Share on other sites More sharing options...
JohnD Posted January 9, 2016 Share Posted January 9, 2016 AH! So what looks like a 'flywheel' isn't that at all, just a 'ng great reduction gear?Thanks!John Quote Link to comment Share on other sites More sharing options...
thescrapman Posted January 9, 2016 Share Posted January 9, 2016 As Nick mentions, the noise of a 1300fwd starting is quite unique. Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted January 10, 2016 Share Posted January 10, 2016 Quoted from thescrapman As Nick mentions, the noise of a 1300fwd starting is quite unique. Yeah..... sounds like something you might hear on an Attenborough wildlife prog - probably in the depths of a jungle.Nick Quote Link to comment Share on other sites More sharing options...
GT6 M Posted January 11, 2016 Share Posted January 11, 2016 Quoted from uksnatcher The search for 'rocking horse poo' shall continue for you then... 😉 Here ye are Gaz, supposed to be the Genuine article M Quote Link to comment Share on other sites More sharing options...
GT6 M Posted January 11, 2016 Share Posted January 11, 2016 the 2.5 pully have got elongated wols aroond the outer rim,to save weight.(think)(think)as they bigger than a GT type, esp if power steering pully addedM Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.