Davidw Posted April 29, 2011 Report Share Posted April 29, 2011 Morning all. Having fited a new Prestige pump kit a year ago, I have now discovered that the slightest left bend on a less than half full tank results in the fuel climbing away and starving the pump. I now realsie that the previous set up with a Lucas filter acted as a fuels reserve on bends although this led to generally inadequate fule supply at high revs. The tank is in really good nick but is not internally baffled - it's an original 5 tank and was NOS when fitted 10 years ago. I don't really wnat to spend hundreds on a new tank - especially with the increase in ethanol which may ruin it within a year or so. Roger Williams speaks of fitting swirl pots. Has anyone any expereince of this and advice on set up? Quote Link to post Share on other sites
john.r.davies Posted April 29, 2011 Report Share Posted April 29, 2011 (edited) David, A'lifter' pump and a swirl pot would be most effective. The lifter keeps the pot full at all times by circulating fuel between it and the main tank, and the pot excludes air, as the fuel is injected tangentially, making it 'swirl' around the circular pot. That brings air bubbles to the centre and top of the pot, where the fuel and bubbles return to the main tank. The take off to the main pump would low and on the preriphery of the pot. A 'solid-state' Facet pump would be a good lifter, and about £35. Most pots for sale are much too big, IMHO, but this one is 1 litre, more than enough and not a bank breaker http://www.flashcustoms.co.uk/base-mount-aluminium-one-litre-fuel-swirl-pot-382-p.asp. The criterion for size is, what is the fastest rate at which your engine will consume fuel, and for how long could the main tank outlet be sucking air? I use one for racing that is 1.25l. If you are road driving then I think that a smaller pot than 1 litre would suffice. That Lucas filter housing would do as a pot. It has a connector on the top which is not usually used and would do for the return, and although the in- and out-puts wouild not be ideal, it would be cost free! John Edited April 29, 2011 by john.r.davies Quote Link to post Share on other sites
Davidw Posted April 30, 2011 Author Report Share Posted April 30, 2011 Hi John and many thanks for the very helpful reply. Sorry for the delay in reply but we've just been away overnight in the TR (and on a full tank she ran beautifully. I did think about the Lucas filter s a swirl pot, but the outlet pipes are only about 5mm. I beleive that general opinion these days is that you need at least 8mm to satisfy the Bosch pump, though I'd be grateful for any other thoughts. Presumably the primer pump might deliver sufficient volume to render such a large input to the Bosch pump unnecessary? Or would all inlets & outlets have to match? Having been thrown out of Physics class at the age of 14 I am a bit vague on these matters? Thanks anyway. I wil certainly consider the initial fule pump you have suggested. I assume that the Swirl Pot would need to be above the Bosch pump, but could also be above the primer pump since it#s pressure could shove the fuel above itself? Quote Link to post Share on other sites
john.r.davies Posted April 30, 2011 Report Share Posted April 30, 2011 No probs, David, just back from a friend's wedding myself! I hadn't heard any criticism of pre-Bosch piping being too small, and even a small Facet will deliver more than enough pressure to push fuel up the few inches you might need. See: http://www.fuelsystem.co.uk/web-facet.pdf 2-10psi depending on model; Boschs do need a small head of pressure to make then work well. I used a Silver top, because I had one to hand. John Quote Link to post Share on other sites
Davidw Posted May 1, 2011 Author Report Share Posted May 1, 2011 No probs, David, just back from a friend's wedding myself! I hadn't heard any criticism of pre-Bosch piping being too small, and even a small Facet will deliver more than enough pressure to push fuel up the few inches you might need. See: http://www.fuelsystem.co.uk/web-facet.pdf 2-10psi depending on model; Boschs do need a small head of pressure to make then work well. I used a Silver top, because I had one to hand. John Thanks again, John. Presumably I can just blank off the sworl pot feeds that I don't need? I was thinking one in, one out, & one tank return makes 3 whereas the swirl pots all seem to have 4. Before I do something stupid, am i on the right lines? Many thanks David Quote Link to post Share on other sites
john.r.davies Posted May 2, 2011 Report Share Posted May 2, 2011 (edited) Thanks again, John. Presumably I can just blank off the sworl pot feeds that I don't need? I was thinking one in, one out, & one tank return makes 3 whereas the swirl pots all seem to have 4. Before I do something stupid, am i on the right lines? Many thanks David Yes to blanking off! I'd love to know why o/e swirl pots have extra ports. I have one and don't use it. John Ps Am I the only person here to use a swirl pot? Anyone else have an opinion? I've advised David to use an old Lucas filter, but I use a purpose built one. J. Edited May 2, 2011 by john.r.davies Quote Link to post Share on other sites
Davidw Posted May 2, 2011 Author Report Share Posted May 2, 2011 Yes to blanking off! I'd love to know why o/e swirl pots have extra ports. I have one and don't use it. John Ps Am I the only person here to use a swirl pot? Anyone else have an opinion? I've advised David to use an old Lucas filter, but I use a purpose built one. J. Hi John and many thanks. I will probably not have the time to sort this out for a feww weeks but when I do I will post again. I will probably use the smallest available pot with small Facet pump and the latest type fuel hose to ensure comapatibility with later fuels. At least I don't have to take the tank out again! Quote Link to post Share on other sites
john.r.davies Posted May 2, 2011 Report Share Posted May 2, 2011 Hi John and many thanks. I will probably not have the time to sort this out for a feww weeks but when I do I will post again. I will probably use the smallest available pot with small Facet pump and the latest type fuel hose to ensure comapatibility with later fuels. At least I don't have to take the tank out again! Plesae let us (me - I'm all alone on swirl pots!) know how you get on. With picture if possible. John Quote Link to post Share on other sites
RobinTR6 Posted May 2, 2011 Report Share Posted May 2, 2011 John I dont have a swirl pot on my 5 but do get a bit miffed when cornering (petrol starvation) and the tank is between 1/4 and 1/2 full(have a Bosch setup on the outside of the boot on the rear chassis rail a la Revington) . As youve noted swirl pots seem a tad expensive and large so I'd be interested in the one you have. Your link didnt work so currently none the wiser. Can you either update the link or let me know where I can view/get a pot like yours. Thanks Robin Quote Link to post Share on other sites
john.r.davies Posted May 2, 2011 Report Share Posted May 2, 2011 (edited) Robin, This one? http://www.flashcustoms.co.uk/alloy-fuel-swirl-pot-1-ltr-bulkhead-mount-384-p.asp The same firm has several, but I only chose them as an illustration - I don't have one of theirs. The one I have is labelled "AH Fabrications": http://www.ahfabrications.com/index.php?cPath=17_4&osCsid=rcrbo7vu6v54q724nfp3rthb26 but I didn't get it from them and it is bulkhead mounted, as below. (No, it's not a TR, but my Vitesse has a TR engine!) The lowest cost anywhere seems to be about £50 - is that a bank buster or not? It's about one tyre, and will last a lot longer. Only you can decide, but they can be four times that or more for fancy ones. As I say, I seriously considered the Lucas filter housing route, and I think it would work, but I got hold of this pot for a lot less (ask no questions) so used that instead. John PS, I think some cars/people, esp. those with a common rail injector system, will use the second swirl pot input for the rail return. The Lucas M/unit will warm fuel more than a rail, so I prefer to send the M/u returned fuel back to the main tank, where it will be diluted with cool fuel and have more opportunity to cool further than in the pot. J. Edited May 2, 2011 by john.r.davies Quote Link to post Share on other sites
josephtr5 Posted May 25, 2011 Report Share Posted May 25, 2011 John Apologies again for breaking into this string but as a new user I am not sure what happened to our exchange on the topic of fuel starvation on a left turn. You had mentioned it could be electrics causing the problem however because it only happens when I have just less than half a tank of petrol and never happens otherwise. I am sure the addition of a swirl pot will cure the issue. I will see whether I can convince a specialiist to install the pot with the lifter pump you suggested. Anyway thanks again your advice. Joseph p.s. Still have not been able to attach a picture but have lots of time for that and not enough in the car. Quote Link to post Share on other sites
RobinTR6 Posted May 28, 2011 Report Share Posted May 28, 2011 Joseph, not sure where you are with this but does sound like petrol starvation, mine occurs between 1/4 and 1/2 and yes mostly on left handers, the [pipe exit on the tank is toward the right hand side, so I guess its to be expected. The later TR6's did have a baffle in the tank, not sure when this was introduced but check that out as well. Robin Quote Link to post Share on other sites
Davidw Posted May 28, 2011 Author Report Share Posted May 28, 2011 Well just to update you all, since posting this thread i got a harmonic noise from the PRV so I rang Malcolm @ Prestige and got one of his noise fix PRVs (which seems to work well ( thanks Malcolm) and so tok the opportunity to ask his view on swirl pots. He doesn't like the idea and suggested getting the tank baffled instead so I am currently looking for someone in Bucks who can do this without launching himself into orbit. Will post again when done Quote Link to post Share on other sites
josephtr5 Posted May 30, 2011 Report Share Posted May 30, 2011 I havent been able to convice a TR specialist to install a lifter pump and swirl pot but if you know anyone who can work on a petrol tank (add baffles ) within 100 miles of London Would be very grateful if you would post. Joseph Quote Link to post Share on other sites
Alec Pringle Posted May 30, 2011 Report Share Posted May 30, 2011 Hi Joseph, David, I can't realistically see any easy route to baffling an old TR tank - by the time you've removed it, thoroughly steamed it out, unzipped it, made up and welded in baffles, zipped it up again, pressure tested, and refitted . . . a lengthy and expensive exercise. It's probably old metal, corroded here and there, and all too likely to let go at some stage in the above process. That is, if you can even find a fabricator willing to work on an old tank . . . . I'd agree with John, having utilised a second standard filter can (less filter) as a successful substitute 'swirl pot' on several applications - including TR5 and TR6. The other applications having been serious race cars with a lot more thirst for fuel than a TR. You can pick up the filter can for less than £20 often enough on ebay, quick and easy solution - with or without a lift pump. If you need to add a small lift pump, again a cheap and easy enough exercise. You could add filter can and pump for a fraction of the cost of baffling a tank, and as a diy exercise. Cheers, Alec Quote Link to post Share on other sites
stuart Posted May 30, 2011 Report Share Posted May 30, 2011 Or just buy one of the newer type baffled tanks. FWIW XJS`s use a separate swirl pot which would make an ideal addition. Stuart. Quote Link to post Share on other sites
Davidw Posted March 12, 2012 Author Report Share Posted March 12, 2012 Update on this one. Had a long and helpful chat with Malcolm at Prestige who suggested I use the original Lucas CAV filter and position it just under the tank, before the Bosch setup. This seems to have worked. The CAV filter is on the RH side fixed to a bracket taken off the lower right tank fixing bolt and it hangs in the wheel well. All connections & hoses are 8mm internal diameter. I tested with about 3 pints of fuel in the tank and it managed several left turns without stalling. (I would normally never let the fuel level below 1 - 1.5 gallons). Quote Link to post Share on other sites
had17462 Posted March 12, 2012 Report Share Posted March 12, 2012 David anychance of some pictures, nick Quote Link to post Share on other sites
john.r.davies Posted March 12, 2012 Report Share Posted March 12, 2012 Well done, David! (And Malcolm!) Clearly there is more than one way to kill a misfire, b ut whatever works for you! John Quote Link to post Share on other sites
Guest ntc Posted March 12, 2012 Report Share Posted March 12, 2012 The orignal Cav filter is IMHO still the best Quote Link to post Share on other sites
Davidw Posted March 12, 2012 Author Report Share Posted March 12, 2012 Send me a pm with your email & I will attach it to an email . I can't use this photo uploader as I can't get an iPhone picture small enough to fit in it. Having said which I suspect that anything bigger than a 1965 Instamatic on 120 film would probably flood the uploader!! Quote Link to post Share on other sites
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