Brett Posted June 19, 2009 Report Share Posted June 19, 2009 (edited) We all know about vapour lock and the obvious answer of the Bosch pump conversion. I've done the proper conversion (Bosch pump mounted under the wing), it's a lot better but I still experience some vapour lock in extreme conditions, like traffic jams in hot swiss summer. Now this may sound naive or stupid, but has anyone thought of cooling the pump with a small electric fan that would be blowing air on the pump? Any experience/opnions on this? Edited June 19, 2009 by Brett Quote Link to post Share on other sites
carld Posted June 19, 2009 Report Share Posted June 19, 2009 We all know about vapour lock and the obvious answer of the Bosch pump conversion. I've done the proper conversion (Bosch pump mounted under the wing), it's a lot better but I still experience some vapour lock in extreme conditions, like traffic jams in hot swiss summer. Now this may sound naive or stupid, but has anyone thought of cooling the pump with a small electric fan that would be blowing air on the pump? Any experience/opnions on this? Brett Spoke with someone recently who had fitted a couple of fans, like the ones used inside of computers. He swore by them, sorry I dont know his name or if he posts on the forum. Quote Link to post Share on other sites
Brett Posted June 19, 2009 Author Report Share Posted June 19, 2009 This is the type of fans I was thinking of. So your friend did see an improvement? Quote Link to post Share on other sites
jean Posted June 20, 2009 Report Share Posted June 20, 2009 If you want to go for a serious fan have a look at liquid cooled motorbikes. You will find different small fans, 10-12cm, in 12v version. Some years ago I had a Bosch pump fitted outside under the wing, it gave more problems than inside as it got heated up by hot road, and especially parking surfaces, so I did put it back inside As you probably know, for proper functioning, a Bosch pump requires a rather important quantity of fuel to circulate, most of it goes back to the tank. If you prevent this it will heat up. In so far the standard TR6 tank outlet is too narrow and is more or less strangling the pump Quote Link to post Share on other sites
Jersey Royal Posted June 20, 2009 Report Share Posted June 20, 2009 If you want to go for a serious fan have a look at liquid cooled motorbikes. You will find different small fans, 10-12cm, in 12v version. Some years ago I had a Bosch pump fitted outside under the wing, it gave more problems than inside as it got heated up by hot road, and especially parking surfaces, so I did put it back inside As you probably know, for proper functioning, a Bosch pump requires a rather important quantity of fuel to circulate, most of it goes back to the tank. If you prevent this it will heat up. In so far the standard TR6 tank outlet is too narrow and is more or less strangling the pump Hi I spoke to Malcolm(Prestige) at last years Malvern. He said a bosch pump should be able to run all day long even in a sealed box and should not overheat. He commented on tank outlet size, as per Jean, also about clean prefilters and also the power supply needs to be of sufficient amps, battery supply, fused , via relay. If fuel is restricted for whatever reason the pump will start to heat up, same applies to an insufficent power supply. Of course low hot fuel is another issue. Cheers Guy Quote Link to post Share on other sites
Richard71 Posted June 20, 2009 Report Share Posted June 20, 2009 Hi I spoke to Malcolm(Prestige) at last years Malvern. He said a bosch pump should be able to run all day long even in a sealed box and should not overheat. He commented on tank outlet size, as per Jean, So should we look to modifying the tank, eg; removing the existing outlet boss and fitting something larger, any ideas on what size outlet is optimum? Richard. Quote Link to post Share on other sites
Jersey Royal Posted June 20, 2009 Report Share Posted June 20, 2009 (edited) So should we look to modifying the tank, eg; removing the existing outlet boss and fitting something larger, any ideas on what size outlet is optimum? Richard. Hi Richard Look at this re tank outlet http://www.prestigeinjection.net/pumps2.htm http://www.prestigeinjection.net/pumps.htm I cant comment on the original tank outlet, although i have an original tank somewhere, will have a look at it tomorrow. I have an ally tank fitted now as my previous tank had been causing blocked filters, due to rust, after a period when i didnt use the car. Regards Guy Edited June 20, 2009 by Jersey Royal Quote Link to post Share on other sites
Richard71 Posted June 20, 2009 Report Share Posted June 20, 2009 Thanks Guy, An aluminium tank is on the shopping list. Could you clarify for me please.... Is the outlet pipe in that case easily removed and replaced with a larger bore, or, is it welded in place and I should then give particular instruction to whoever I buy from. Regards, Richard. Quote Link to post Share on other sites
IanR Posted June 20, 2009 Report Share Posted June 20, 2009 Hi Folks, As a matter of intererest you may like to know what it was like in the past.. In the 70's I had a TR6 and have the distinction of having broken down on Westminster Bridge in the Friday night rush hour .. A pack of frozen peas was a 10 minute walk away (OK hard to believe that we used to commute accross London in the rush hour in those days but we did). I had the cooling coil but the summer of 76 (or was it 75 I cannot recall) was a steamer) just like we were promised last year and also this, but so far zippo. Anyway. I drilled a large hole in the rear LH wheel arch and fitted a fan, NO not a computer fan, they were not, as it were, invented then , I used a scrap yard heater fan from a large luxury car ...I think a Merc ... but not sure. This was wired to a dash switch (no relays then) and it worked a treat, however the noise of the fan over the rest of the din is difficult to remember........ Also it has to be said, I wrecked a good TR6 wheel arch in the process... But I hope that the demise of CYX462H was not of my doing. Today I run my TR5 on the original Lucas pump with a Facet lift pump between tank and Lucas. No fan required so far BUT no summer yet either .... So I cannot claim, as yet, any hot weather benefits Cheers Quote Link to post Share on other sites
Alec Pringle Posted June 20, 2009 Report Share Posted June 20, 2009 Hi Guy, "a bosch pump should be able to run all day long even in a sealed box and should not overheat." Cool theory, I've heard that one before. Good stuff, theory. So why is it that all good German manufacturers stick their Bosch pumps somewhere under the car - where it has the benefit of a large sheet metal heat sink, a shield below to protect from reflected road heat, and a carefully sorted airflow over the pump ? Not to mention the competing cars I see in the service areas on continental rallies - where even more effort is made to ensure the Bosch pump has both a heftier heat sink and a better airflow than standard ? Not always underbody mounted, in some cases a boot installation complete with fan cooling, just as Brett was pondering. Cheers, Alec Quote Link to post Share on other sites
jean Posted June 20, 2009 Report Share Posted June 20, 2009 In general the tank outlet should be of the same size as the pump inlet A coarse prefilter should do the job as it seems that roller vane pumps are not sensitive to fine dirt, but a micro filter has to be fitted downstream. Intank fuel pumps are only protected by a simple mesh. At this time I run my system without prefilter, this since 98, only a Bosch high pressure filter after the pump, my tank outlet is 9mm compared to 6mm original what is an increase of more than 100%. I have seen all kind of configurations, many using the original filter. Some work, others don't. To many drivers reliability is not an issue as their cars are passing most of the time in the garage Quote Link to post Share on other sites
Jersey Royal Posted June 21, 2009 Report Share Posted June 21, 2009 Hi Guy, "a bosch pump should be able to run all day long even in a sealed box and should not overheat." Cool theory, I've heard that one before. Good stuff, theory. Cheers, Alec Hi Alec Not my theory but a i said that of Malcolm at Prestige. If heat sinks are necessary on a Tr system and fans, why is that none of the Tr suppliers have taken this step. Overkill? Cost? I have thought in the past of fitting a fan in the wheel well, but didnt get far, problems arose with waterproofing issues, once youve cut a hole in your bodywork. Redid electrics, checked all pipework sizes, filters etc, pump runs quite and no further issues. Cheers Guy Quote Link to post Share on other sites
jean Posted June 21, 2009 Report Share Posted June 21, 2009 On modern cars all fuel systems are moved outside the inner body for safety reasons and many German car makers use in-tank pumps with or without additional feeder pumps. Imho rally cars have the pumps fitted outside for quicker maintenance , and it might be less dramatic to spoil fuel on the road than in the cabin When fitting a pump and eventually the filter in the wheelwell serious protection is a good idea if you don't wish an item to be perforated by stones or rubbish lying around on the road. Remember the Concorde crash at Paris Quote Link to post Share on other sites
RogerH Posted June 21, 2009 Report Share Posted June 21, 2009 Hi Jean, sadly all the bits on the Concorde were in the right place, internal fuel pumps etc, unfortunately the stupid French (sorry Badfrog and co) filled the wing tanks to brimming. When the tyre exploded due to debris( and the fact that it was pointing the wrong way - a little bit) the rubber hit the underside of the wing and the shock wave created inside the tank had nowhere to go (as it was filled completely to the top) blew out the rear spar. The shrapnel cut through some electric cables and a small spark ignited the flood of fuel pouring out of the tank into the main landing gear wheel bay. Remove any one part of the story and it would not have been a story alas!! Roger Quote Link to post Share on other sites
roy53 Posted June 21, 2009 Report Share Posted June 21, 2009 like ianR i also run my 5 on the lucas pump and facet feeder pump,having had a bosh pump on when i got the car and getting the usual problems on hot sunny days,and as soon as i fitted a nice new s/steel exhaust mounted as close to the boot floor as poss to give as much ground clearance as poss[a mistake]this heated up the boot/fuel even more ,and after a lot of trial and erorr gave up the bosh and as the car was also a concorse car i went for the origonal lucas set up with the later fuel returning into the tank as the TR6 rather than retuning to the pump as TR5. This was all ok untill a european summer holiday when as soon as the temp rose the dreaded pump probs started,as i had been thinking of the feeder pump system i had put one in my spares pack this was quickly fitted and the problem went .8 years later and still no problems.I supose that means the next hot day i will need the pack of frozen peas Lucas for me ROY Quote Link to post Share on other sites
Jersey Royal Posted June 21, 2009 Report Share Posted June 21, 2009 (edited) like ianR i also run my 5 on the lucas pump and facet feeder pump,having had a bosh pump on when i got the car and getting the usual problems on hot sunny days,and as soon as i fitted a nice new s/steel exhaust mounted as close to the boot floor as poss to give as much ground clearance as poss[a mistake]this heated up the boot/fuel even more ,and after a lot of trial and erorr gave up the bosh and as the car was also a concorse car i went for the origonal lucas set up with the later fuel returning into the tank as the TR6 rather than retuning to the pump as TR5. This was all ok untill a european summer holiday when as soon as the temp rose the dreaded pump probs started,as i had been thinking of the feeder pump system i had put one in my spares pack this was quickly fitted and the problem went .8 years later and still no problems.I supose that means the next hot day i will need the pack of frozen peasLucas for me ROY Roy If its a concorse car, dont you have a problem with having a s/steel exhaust? And also having fitted a feeder pump. Or is it just a matter of losing a few points, that is of course if you show it. Cheers Guy Edited June 22, 2009 by Jersey Royal Quote Link to post Share on other sites
Jersey Royal Posted June 21, 2009 Report Share Posted June 21, 2009 (edited) Sorry Duplication Edited June 21, 2009 by Jersey Royal Quote Link to post Share on other sites
BrianC Posted June 22, 2009 Report Share Posted June 22, 2009 On modern cars all fuel systems are moved outside the inner body for safety reasons and many German car makers use in-tank pumps with or without additional feeder pumps. Imho rally cars have the pumps fitted outside for quicker maintenance , and it might be less dramatic to spoil fuel on the road than in the cabin Another great idea - in theory, but a complete pain in the arse when the pump fails. This happened to a Westfield Seven with a new SU pump on a recent SBMC event. Everyone who stopped to help said "hit it with a hammer", but the pump was buried in the tank, which was itself not terribly accessible and the car had to be ignominiously towed home (but at least via the pub). I'm so pleased that both our TRs have a mechanical pump which is easily accessible and has a hand-priming lever. Quote Link to post Share on other sites
tonyq Posted June 22, 2009 Report Share Posted June 22, 2009 Hi Brett I've been running a fan-cooled Lucas pump for years with no overheating problems at all. The pumps's in the usual place, but is in a tube (made from something like a big yoghurt pot with the ends cut off) about 1 cm bigger diameter. That gives room to put a 12V 4 inch computer fan on top, blowing air downwards through the tube and out the bottom (about a 1cm gap from the boot floor). The fan's driven from the same supply that switches the relay which provides 'direct' power to the pump. The only thing I've changed in the system is making the circulation back to tank rather than back to filter. Hasn't let me down yet, touch wood. Quote Link to post Share on other sites
Jersey Royal Posted June 22, 2009 Report Share Posted June 22, 2009 Gents, Been thinking about the clever use of 12v computer fans. When these fans start, do they create a spark? or whats the possibility of one? With modern fuels there will always be some smell of fuel within the boot, some more than others, so therefore petrol vapours permating rubber tubing, or bad joints etc Petrol vapours plus spark = Big bang Or am i being overly cautious. Regards Guy Quote Link to post Share on other sites
Brett Posted June 22, 2009 Author Report Share Posted June 22, 2009 Oooops, good point Jersey Royal! It's great to read so many answers by the way, thank you all Quote Link to post Share on other sites
Jersey Royal Posted June 22, 2009 Report Share Posted June 22, 2009 Oooops, good point Jersey Royal! It's great to read so many answers by the way, thank you all Brett, I dont know if there would be a spark, or whether it would require a special fan. Can anyone shed any light. Cheers Guy Quote Link to post Share on other sites
Richard71 Posted June 22, 2009 Report Share Posted June 22, 2009 And just to be extra AAA+ cautious, you might want to make certain the blades of the fan are of the anti-static type as used in petrochem installations. Or is that simply overdoing it? Dunno? Richard. Quote Link to post Share on other sites
jean Posted June 22, 2009 Report Share Posted June 22, 2009 (edited) The small electric fans do not work as the well known classic electric motors, they have no slip ring collector and so no sparking possible. I think they rotate by changing the electro magnetic field in permanent magnets or something like that. Every time I buy a cheap new thingy I first take it apart, resulting in that I have to buy a new one Edited June 22, 2009 by jean Quote Link to post Share on other sites
roy53 Posted June 22, 2009 Report Share Posted June 22, 2009 Roy If its a concorse car, dont you have a problem with having a s/steel exhaust? And also having fitted a feeder pump. Or is it just a matter of losing a few points, that is of course if you show it. Cheers Guy the word being WAS,answers that. Roy Quote Link to post Share on other sites
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