Menno van Rij Posted September 12, 2016 Report Share Posted September 12, 2016 Many, many moons ago, I mentioned here on the forum a white TR5 - an early TR5. The 20th ever built. My friend Peter is rebuilding the car. The 4th Triumph he's been working on. A bunch of you must know him: in the past, he won the International's concours with his red TR4. According to stories, ST built a bunch of 250 TR250 for the US market. And then built 10 RHD TR5s. Also to be tested and tried on the Continent. Motoring journalists on the continent wanted to try LHD TR5s and Triumph built 10 cars. (#11 to 20). This being the 20th car. This very car was taken to the London Motorshow and was used for photoshoots etc. But it was the last one built with... the fuel pump under the bonnet! It proved to be impossible to keep the temperature under control with the ambient under bonnet temperature. So ST seized production and changed to the well known lay out of the pump at the back! Peter, the current owner and restorer wants to give it a try. But not without a struggle. He needed the original wiring loom for the wiring of the front end pump. After a long search, he found one! But not in a good shape. So he combined the original loom with a later loom, incorporating the rear end pump wiring into the harness. Thus making it possible to switch from the front end pump to the rear end pump without too much hassle when he needs to change it. The car came with all sorts of paperwork. That shows that the original engine (#22 or so) seized up within days after being delivered to the motoring press... It was replaced with another engine. Papers show that ST changed the engine number of the later engine into the lower number! In short: two engines with the same number. The original engine is still in use in a... TR6 in the UK or Ireland! The original TR5 engine that came with the car must have seized up again. The crank being the culprit. It's not the first TR5 Peter is restoring and he noticed that the earlier engines are not the same as the later engines. Making it difficult to examine how to overcome the seizing of these engines. Thus he opted for a TR6 engine he had in his garage. The current TR5 sits on a pedestal, waiting to be examined and restored. But in an ideal world, Peter would like to swap the TR6 engine for the TR5 engine thet was originally in the car. If someone knows more... Anyway, time for a load of pics: Quote Link to post Share on other sites
ianhoward Posted September 12, 2016 Report Share Posted September 12, 2016 Looking very nice indeed!!! Cheers Ian Quote Link to post Share on other sites
stuart Posted September 12, 2016 Report Share Posted September 12, 2016 Interesting pump mounting bracket, I thought they were mounted the same way as in the rear as on the early 5 wheelarch there is the same 3 mounting holes. Stuart. Quote Link to post Share on other sites
Guest Posted September 12, 2016 Report Share Posted September 12, 2016 (edited) I guess that Peter did extensive research on that matter. He was quite specific about this bracket. And prettig sure about it. It will be difficult to start the car when hot, I think. And I would be surprised when it will be changed. Edited September 12, 2016 by Menno van Rij 2 Quote Link to post Share on other sites
stuart Posted September 12, 2016 Report Share Posted September 12, 2016 John Sykes (TR Bitz) had one of the very early ones and that was still running underbonnet pump last time I saw it not that long ago. Stuart. Quote Link to post Share on other sites
JohnG Posted September 13, 2016 Report Share Posted September 13, 2016 Lovely Job! Quote Link to post Share on other sites
Gary Flinn Posted September 13, 2016 Report Share Posted September 13, 2016 Excellent workmanship :) I'm not surprised Triumph moved the Pump to the boot, my original Lucas Pump gets very warm even in the boot, with all the Engine heat circulating I'm sure fuel vaporization will be a real problem on a hot day :( I've fitted an aluminium Cooling Heat Sink to my pump, although I haven't been on any long journeys in the Summer to see if it works?! Quote Link to post Share on other sites
Andrew Smith Posted September 13, 2016 Report Share Posted September 13, 2016 The late Dr Micheal Bingley ran his early TR6 with the pump fitted in the engine bay for years without any problems. Cheers Andrew Quote Link to post Share on other sites
Peter Cobbold Posted September 13, 2016 Report Share Posted September 13, 2016 If it gives problems with ethanol fuels I would think about fitting a low pressure pump in the boot to help the underbonnet Lucas 'suck' liquid fuel rather than vapours. Peter Quote Link to post Share on other sites
RogerH Posted September 14, 2016 Report Share Posted September 14, 2016 Seeing the pump fitted under the bonnet makes me think that a cooling air duct from the front (as per a duct for the carb intakes) would be a benefit. Add a cowl around the pump and then duct the exiting air downwards and rearwards under the car. In fact why isn't that done in the boot? Roger Quote Link to post Share on other sites
Gary Flinn Posted September 14, 2016 Report Share Posted September 14, 2016 Seeing the pump fitted under the bonnet makes me think that a cooling air duct from the front (as per a duct for the carb intakes) would be a benefit. Add a cowl around the pump and then duct the exiting air downwards and rearwards under the car. In fact why isn't that done in the boot? Roger I thought about rigging up one of the small PC Type Cooling fans and combined heat Sinks and then installing some small diameter ducting to feed cold air to the Fan/pump? It would involve a bit of cutting of the bodywork somewhere to get the cold air in from outside, I haven't bothered and have fitted an heat sink only at the moment. Hopefully this should help keep the Pump cool and stop the dreaded Ethanol doing its thing . Quote Link to post Share on other sites
RogerH Posted September 14, 2016 Report Share Posted September 14, 2016 (edited) Hi Gary, the boot space is a very confined volume. You need a cool airflow. The trapped air in the boot will simply warm up. The pump will produce far more watts of heat than a small computer fan will handle in my opinion. Many modern cars have the pump in a wheel arch or similar. Perhaps consider bolting your heatsink to an inner wing (no wheel arch liners) and using fluid filed copper piping around the pump and heatsink. Having it under the bonnet is nice as there are no hoes to cut in the body work. Aircraft have the pumps continuously immersed in the fuel tanks :blink: - they don;t often explode :o Roger Edited September 14, 2016 by RogerH Quote Link to post Share on other sites
jean Posted September 16, 2016 Report Share Posted September 16, 2016 Roger I think several modern cars have immersed fuel pumps with the electrical connections outside the tank. The problem with aircraft is that sometimes they do not fill all tanks, an empty tank with sparking connections is looking for problems... remember TWA. Quote Link to post Share on other sites
amclpreston Posted September 19, 2016 Report Share Posted September 19, 2016 (edited) I owned LHP293F ( CP6 ) for 4 years in the mid/late '70's. As I recall, the underbonet fuel pump was surrounded by metal fuel tubing coiled round it, presumably for cooling purposes. In 4 years ownership, I can recall less than a handful of occasions when the car cut out due to the vapourisation thing. All on very hot summer days, idling for long periods, in heavy traffic. Edited September 19, 2016 by amclpreston Quote Link to post Share on other sites
Peter V W Posted August 4, 2021 Report Share Posted August 4, 2021 Any update on this car. CP20 ? Quote Link to post Share on other sites
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