john.r.davies Posted May 16, 2017 Report Share Posted May 16, 2017 (edited) Been helping a friend with a Land Rover restoration; engine out today, and spotted this (pic) After all the misguided external oil supplies to Triumph cylinder heads (YSoYD) and Landie's do it all the time! John Edited May 16, 2017 by john.r.davies Quote Link to post Share on other sites
Nigel Triumph Posted May 16, 2017 Report Share Posted May 16, 2017 It's Beelzebub's business, at least when fitted on a Triumph. Nigel Quote Link to post Share on other sites
stuart Posted May 16, 2017 Report Share Posted May 16, 2017 Been helping a friend with a Land Rover restoration; engine out today, and spotted this (pic) After all the misguided external oil supplies to Triumph cylinder heads (YSoYD) and Landie's do it all the time! John So do XK engined Jaguars but the pipework is of the correct size and drawn from a better place on the oil system Stuart. Quote Link to post Share on other sites
pfenlon Posted May 16, 2017 Report Share Posted May 16, 2017 My TR6 when I brought it from the USA had the rocker oil feed mod fitted, and by the look of the gunge on the pipe, it had been there for years. But even with this fitted the rocker shaft is heavily worn and needs replacement. Quote Link to post Share on other sites
Tom Fremont Posted May 16, 2017 Report Share Posted May 16, 2017 I've got 115K miles on a TR250 engine with the rocker feed line. Rockers were re-done to better than original standards with bronze bushes and hard chrome plated shaft, and show no detectable wear in that time. Oil pressure is at the high end of the specified range ( 65 psi @ 2000 rpm when hot - yes, it has a 16 row oil cooler with 'stadt ) and consumption at 3-4K miles per quart depending on driving style. No valve guide seals. So it's been a complete success in my experience. The only difficulty is getting the installation leak tight. Cheers, Tom Quote Link to post Share on other sites
oldtuckunder Posted May 16, 2017 Report Share Posted May 16, 2017 Done properly with a restricted pipe and the oil way in the head blocked off so that it only feeds enough oil to the rockers then fitting one probably isn't going to do any harm. The trouble is that many/most aren't installed correctly. And then you get back to the issue that the standard rocker gear doesn't need much lubrication to operate satisfactorily to quite high rpm's and believe it or not the standard system is designed to deliver the correct amount for the rpm that the engine is doing, not squirt as much as it can up the pipe into the rocker chamber based on the oil pressure i.e. with an external feed you will get as much into the rockers at 65psi 2K as you will at 65psi 6K (give or take) All too much oil in the rocker box is going to do is try and be sucked down inlet valve guides, and leak out the gasket, and blow out the PRV. Rocker shafts are cheap and you can change them by removing the rocker cover, steal oil from the oil gallery and accidentally starve one of the critical bearings fed from it and you have an expensive engine out problem, and why? so you have a piece of blingy pipe on the engine that says "Race". If you have needle roller rockers I understand the external feed is nearly essential. My 2.0 6 pulls silly revs compared to most 2.5's and after 4 years on this winters rebuild there wasn't the slightest trace of wear on the rocker shaft. Alan Quote Link to post Share on other sites
Tom Fremont Posted May 16, 2017 Report Share Posted May 16, 2017 ...and in fact I don't have one on my show car with its steroidal cam, high c/r and triple DCOEs. A total toy, it doesn't get 1000 miles a year. Tom Quote Link to post Share on other sites
BlueTR3A-5EKT Posted May 16, 2017 Report Share Posted May 16, 2017 I was more intrigued by the wire 'knitting' to lock the bolt heads. Lazy but Cute is a good way to describe the technique. Peter W Quote Link to post Share on other sites
KiwiTR6 Posted May 17, 2017 Report Share Posted May 17, 2017 (edited) Took mine off as recommended by many here and now I can sleep at night There still appears to be plenty of oil floating around under the rockers cover from what I can see. Gavin Edited May 17, 2017 by KiwiTR6 Quote Link to post Share on other sites
Guest Posted May 17, 2017 Report Share Posted May 17, 2017 Ask the people over at the Spitfire Club. The 1500 was prone to overheating and a lot of the 1500 fitter an off the shelf kit. Quote Link to post Share on other sites
john.r.davies Posted May 17, 2017 Author Report Share Posted May 17, 2017 Peter W, Even the owner doesn't know what those bolts are for, or why they are wired, so probably from the history were original production feature. What's wrong with the wiring, to deserve the name "knitting"? The wires are properly angled to prevent them undoing. Menno, You are right about the Spawnne being popular among Spitfire owners, and when you describe it as an "off the shelf kit", but it's a thoughtless and exploitatative bit of kit, marketed as 'competiton' but in fact pure bling! It can be added if properly fitted and restricted as said above, but when a riocker shaft needs so little, why bother? John Quote Link to post Share on other sites
oldtuckunder Posted May 17, 2017 Report Share Posted May 17, 2017 Even the owner doesn't know what those bolts are for, or why they are wired, so probably from the history were original production feature. What's wrong with the wiring, to deserve the name "knitting"? The wires are properly angled to prevent them undoing. Interesting point on wiring things. At a competition the other weekend whilst being scrutineered (and we know they all like to find something) it was suggested (not required) that in the future I might like to consider putting a large jubilee clip around the oil filter canister and wiring it off to another point to prevent it undoing. Now not actually a bad idea but had a few other experienced competitors scratching their heads as they had never had it suggested to them. Of course when you go around a car there are many things that might be safer if wired. I was always amazed on the XJS how many bolts were wired straight out of the factory! Alan Quote Link to post Share on other sites
BlueTR3A-5EKT Posted May 17, 2017 Report Share Posted May 17, 2017 It is a personal thing.... I am originally from the UK civil aircraft world so single strand wire locking was only used in special situations. Twisted double wire was the norm. This link gives a view of the technique most commonly adopted and specified in The Civil Aircraft Inspection Procedures published by the CAA. http://byrongliding.com/technical/lockwiring/ Peter W Quote Link to post Share on other sites
KiwiTR6 Posted May 17, 2017 Report Share Posted May 17, 2017 Interesting point on wiring things. At a competition the other weekend whilst being scrutineered (and we know they all like to find something) it was suggested (not required) that in the future I might like to consider putting a large jubilee clip around the oil filter canister and wiring it off to another point to prevent it undoing. Now not actually a bad idea but had a few other experienced competitors scratching their heads as they had never had it suggested to them. Of course when you go around a car there are many things that might be safer if wired. I was always amazed on the XJS how many bolts were wired straight out of the factory! Alan Several years back I had the unfortunate experience of having the oil filter partially undo itself on my Buell whilst out riding. It had been done up good and tight, but was a new long-body version which because of the extra length was apparently more prone to the considerable vibration from the Harley engine. Fortunately I managed to stop before it came off completely and lost all of the oil, but it made one hell of a mess. Subsequent to that I fitted a jubilee clip and lock wire and would probably do the same on a competition car just for peace of mind. Gavin Quote Link to post Share on other sites
stuart Posted May 18, 2017 Report Share Posted May 18, 2017 Interesting point on wiring things. At a competition the other weekend whilst being scrutineered (and we know they all like to find something) it was suggested (not required) that in the future I might like to consider putting a large jubilee clip around the oil filter canister and wiring it off to another point to prevent it undoing. Now not actually a bad idea but had a few other experienced competitors scratching their heads as they had never had it suggested to them. Of course when you go around a car there are many things that might be safer if wired. I was always amazed on the XJS how many bolts were wired straight out of the factory! Alan Thats because Jaguar used to do a lot of racing. Stuart. Quote Link to post Share on other sites
Tom Fremont Posted May 18, 2017 Report Share Posted May 18, 2017 For bolts which require tightening to more than 50% of their proof load ( 80% is pretty typical ) lockwiring serves no technical / engineering function except perhaps as a visual protocol signifying said tightening has taken place. Absent such tightening, bolted connections subjected to cyclic loading will fail in shear before lockwires are affected. Where the design diligence is complete, the specified torque will ensure the bolts never loosen in the application. If there is any current justification for the practice I'd like to see it. Here in Cincinnat, Ohio, formerly the world's headquarters for machine tools, the practice disappeared before the start of my career almost 40 years ago. Cheers, Tom Quote Link to post Share on other sites
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