TR674 Posted December 8, 2015 Report Share Posted December 8, 2015 Hello good people. I have original Lucas fuel pump in reasonable condition. I have recently started to use 98 octane, mainly for better cold starts (it will fire up on first attempt, rather than 4th or 5th attempt on lower octane). Since using 98, I have noticed a wine/buzz (louder than normal) from the fuel pump, especially on a fresh tank. I also have a submerged fuel additive canister for unleaded fuel. Is there any additional chemicals in higher octane fuel that may upset the Lucas pump? My next tank full will be a lower octane to see if the pump quietens down. Or is it a sign to change over to a Bosch system?? Quote Link to post Share on other sites
Alec Pringle Posted December 8, 2015 Report Share Posted December 8, 2015 "I also have a submerged fuel additive canister for unleaded fuel." Throw it away, it's useless and surplus weight at best, potentially damaging at worst. The PI engine was designed for petrol of 100/101 octane, even 98 is pushing its lower limits, trying to run a PI engine on anything less than 98 is inviting disaster. Clean the system, the world is not short of decent fuel system cleaners . . . . . If the performance does not improve, send the relevant components to Neil Ferguson here in the UK for reconditioning - Andrew P in Perth will tell you what a difference it makes ! link to Andrew - http://www.tr-register.co.uk/forums/index.php?/user/8372-andrewp/ He can also point you at me via email if you need any further thoughts . . . . . Cheers Alec Quote Link to post Share on other sites
stuart Posted December 8, 2015 Report Share Posted December 8, 2015 What exactly do you mean by a "Submerged fuel additive canister for unleaded fuel"? Stuart. Quote Link to post Share on other sites
john.r.davies Posted December 8, 2015 Report Share Posted December 8, 2015 Like this? They are variously claimed to provide lead substitute, raise the octane of the fuel and make your car irresistible to women. On all counts they are a complete sham and a diddle. John Quote Link to post Share on other sites
jamesStag Posted December 8, 2015 Report Share Posted December 8, 2015 Hi Alec, I was interested in your post above, particularly ".... even 98 is pushing its lower limits, trying to run a PI engine on anything less than 98 is inviting disaster..." I have seen other similar comments folks make about running on 97/98 fuel. So perhaps this is a bad time to admit that I run mine on just std 95 fuel, sometimes even supermarket 'lemonade' as some have called it... ! If the price is good. The car appears to run just fine, smooth, starts well, goes well, no pinking (but in past I did retard it by around 2/3 of a turn on the dizzy vernier as could hear a little pinking at 'full-right boot'. but not now) The only thing I use is a lead replacement additive and that does have octane boost, but I don't know how effective that element is (Valvemaster - but Peter C's recent posts then strike a little worry about the ferrocene in it... ) Am I flirting with disaster?? I'll get me coat if needed... Cheers, J. Quote Link to post Share on other sites
TR674 Posted December 9, 2015 Author Report Share Posted December 9, 2015 Stuart, I honestly don't know, looks like a small pill bottle with a magnet around the middle. My mechanic endorsed it, so it any problems occur I know who to see..... Thanks Alec, I'll get in touch with Andrew. John, if those claims are correct, I would strap one to my wrist, never mind the car.......... Quote Link to post Share on other sites
AndrewP Posted December 9, 2015 Report Share Posted December 9, 2015 Im here if you need a hand with anything. I have most of the bits (somewhere in my mess!) needed to make a PI system go well, so if you want me to help/have a look at anything then just give me a shout (I`ll PM you my mobile) There are a few of us in Perth, so more than happy to help out. Andy (of Mk1PI fame) and Tony Millward is another top guy here and incredibly helpful, I think Tony is busy putting in a V8 into his 6 at the moment as hes not on here much these days. I can absolutely recommend Neil over in the UK as well. Nice bloke to deal with and the quality of his work is 2nd to none. The Lucas pump for all its sins is a workhorse. Its a motor, connected via a plastic drive dog to a pump mechanism. The only thing that can fail is the seal between the pump and motor and the motor bushes/brushes/thrust washer inside. You`ll probably find the bag of metal you have in your tank is blocking the outlet! It serves no purpose other than rattle around in your tank. Stick with a good quality fuel and valve saver from Supercheap/Repco once in a while and you`ll be fine. Anyway..perhaps see you around. Cheers Andrew Quote Link to post Share on other sites
TR674 Posted December 10, 2015 Author Report Share Posted December 10, 2015 Thanks Andrew. I have met Tony a few times, a very helpful Triumph owner. Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2015 Report Share Posted December 10, 2015 Hi James, CP engines in particular will not thank you for feeding the horses on eurobox hay rather than proper oats . . . . . back in the day I preferred to dope my TR5 and TR6 fuel up to 102-103 octane, the performance difference against 100 octane was significant, and 98 wasn't worth wasting time with. To run 95 you need to wind the timing so far out that you might as well be running a USA spec engine . . . . not PI. TR6 engines won't tolerate ANY pinking for long . . . . . the small detonations of pinking tend to turn rapidly into a large detonation and an even larger bill . . . . . I've seen that happen in just one lap of Goodwood in the days when it was a sprint circuit. Think £5K or whatever invoice to follow . . . . . Cheers Alec Quote Link to post Share on other sites
nowtelse2do Posted December 10, 2015 Report Share Posted December 10, 2015 Alec, mine's a CR with unleaded c/head, should I cease with the 95 pee. It runs ok (well I think it does) Dave Quote Link to post Share on other sites
Peter Cobbold Posted December 10, 2015 Report Share Posted December 10, 2015 My Lucas pump whined for 100,000 miles and was still pumping OK. The pitch fell and rose with the indicators, so it wasn't even getting a good voltage feed. But UK is not as warm as Perth. Peter Quote Link to post Share on other sites
BlueTR3A-5EKT Posted December 10, 2015 Report Share Posted December 10, 2015 (edited) Hold on.... It is mid summer in upside down land. so 50 c plus in the shade? Don't Lucas PI pumps often exhibit a whine when hot or running in high ambient temps? Let alone the fuel vaporisation issue with today's lead free fuel. Think Dr Bingley and his concerns/efforts at this point. Andrew - Check the operating voltage at the pump white wire in the boot - if low compared to the battery voltage, add a fat cable (alternator big brown wire size) via a relay to the pump from the battery. Add in a crash/inertia switch if not already fitted. Edit: Check the fuel pump earth cable is good quality and making best contact too. Does your pump go quiet just after filling the tank? That'll be nice cool fuel cooling the pump. When next it howls wrap a bag of frozen peas or frozen wine/beer chiller round it see if that shuts it up. Have you got a local airfield? Would they possibly like to sell a couple of gallons of Avgas or 100/130 or 100LL or whatever the latest spec of fuel is for piston engine aircraft. Give it a try to see if it stops the probs. Not cheap though. https://en.wikipedia.org/wiki/Aviation_fuel Not sure what you have put in the tank but as mentioned above those items proved to be useless in Europe. Try a liquid lead substitute additive (Nulon) in the fuel to assist in lubricating the pump gears and MU rotor and shuttle. Perhaps << http://www.supercheapauto.com.au/online-store/products/Nulon-Lead-Substitute-500mL.aspx?pid=105137&menuFrom=60402#Recommendations>> Cheers Peter W Edited December 10, 2015 by BlueTR3A-5EKT Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2015 Report Share Posted December 10, 2015 The realistic upper compression ratio limit for 97-98 octane fuel in our aged engines is 9.0:1 Any 6-pot TR engine built with PI will be running a compression ration above 9.0:1, and therefore it requires 100 octane fuel if you are using the original timing . . . . . . US spec 6s are a different story, with a cr of less than 8.0:1 they'll run on any old jungle juice down to maybe 91 octane . . . . even the earlier 250s were only about 8.5:1 if I remember right, which would be quite happy on Euro standard 95 octane fuel. Avgas is one means of upping the octane count, but from all I've heard modern Avgas is not what it was in the 60s and 70s, surprise surprise . . . . . and I wouldn't be wanting to use more than 20% Avgas by volume in an Avgas and road fuel blend. The stuff was, after all, formulated for relatively large and relatively slow speed (as in rpm) engines running at altitude in conditions of very lean burn . . . . . with the paradoxical additional requirement of being able to run rich as blazes in full bore takeoff conditions. Even back in the 70s a PI TR6 ran like a bag of nails on straight Avgas, 40% aviation to 60% motor spirit was as high as you could reasonably go with judicious tweaking of the timing. Cheers Alec Quote Link to post Share on other sites
TRTOM2498PI Posted December 10, 2015 Report Share Posted December 10, 2015 I often put the odd 20 litres of Avgas in mine. 100LL. It is not too expensive either. Runs very nicely with a lovely Grey coloured tail pipe. Cheers. Quote Link to post Share on other sites
Peter Cobbold Posted December 10, 2015 Report Share Posted December 10, 2015 Alec, A agree about the low compression heads. But disagree about the 9.5 heads themselves needing high octane.The carb 9.5:1 engines run fine on 95RON. I run 8.5:1 compression with 16BTDC static, standard c/f swing and 6 psi boost, making an effective CR around 10:1 and it doesn't pink on 95RON. The reason the PI engines can need high octane is the PI itself and specifically its lack of acceleration enrichment. I found this explanation in Richard Stone's textbook ** Sudden wotting the throttle leds to slow fuel evaporation and a significant percentage wets the manifold and flows only slowly to the inlet valve. The lighter components evaporate off the walls during liquid flow, but these are the low octane hydrocarbons. The good stuff - the less volatile aromatics- stay in the liquid film and take a second or so to flow to the inlets and during that time the engine can knock. The quick and easy cure is high octane fuel, which the engine only needs for second or two after wot. The engineering cure would be a 'throttle pump' type of transient enrichment, that defeated Lucas.Richer mixture burn slower and kill the pinking. ** https://books.google.co.uk/books?id=afYcBQAAQBAJ&pg=PA60&lpg=PA60&dq=manifold+fractionation+%2B+%22+Richard+Stone%22&source=bl&ots=CjVuq0-vGQ&sig=VbdfPnnOlB3NEwbrjU2LIRyPPxU&hl=en&sa=X&ved=0ahUKEwj3-ffUiNLJAhVM0hoKHfpnC6oQ6AEIIjAB#v=onepage&q=manifold%20fractionation%20%2B%20%22%20Richard%20Stone%22&f=false Peter Quote Link to post Share on other sites
Peter Cobbold Posted December 10, 2015 Report Share Posted December 10, 2015 (edited) I often put the odd 20 litres of Avgas in mine. 100LL. It is not too expensive either. Runs very nicely with a lovely Grey coloured tail pipe. Cheers. I'd not post that Tom, hefty fine if caught.......defrauding HMRC etc The reason its cheap is because for some unfathonable reason fliers aren't expected to pay tax on their petrol. Not to mention the lead .... Peter Edited December 10, 2015 by Peter Cobbold Quote Link to post Share on other sites
kcsun Posted December 10, 2015 Report Share Posted December 10, 2015 Daft idea??? If this gizmo was just "thrown" in the tank could it occasionally just be blocking or partially blocking the outlet flange???? kc Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2015 Report Share Posted December 10, 2015 Hi Peter, the only carb 6-pots above 9.0:1 that I can bring to mind were the GT6 and 2000 at 9.25, both of which preferred 5 star to 4 star . . . . at least on their specified timing back in the day. Cheers Alec Quote Link to post Share on other sites
john.r.davies Posted December 11, 2015 Report Share Posted December 11, 2015 Peter, You have written before about the lack of acceleration enrchment on Lucas Pi, so I hesitate to suggest: An additional injector. I've seen high performance cars that have a second set of injectors, sometimes directed at the throat of the intake, that cut in at high speed or deep throttle. But could just one provide enough, if sited at the front of the PI plenum, be enough? Keeping it simple, Sir! An equally simple switch on the throttle pedal to turn it on and squirt continuously until the pressure came off the throttle. It might even run off the PI pump. John, just thinking aloud. Quote Link to post Share on other sites
Peter Cobbold Posted December 11, 2015 Report Share Posted December 11, 2015 (edited) Peter, You have written before about the lack of acceleration enrchment on Lucas Pi, so I hesitate to suggest: An additional injector. I've seen high performance cars that have a second set of injectors, sometimes directed at the throat of the intake, that cut in at high speed or deep throttle. But could just one provide enough, if sited at the front of the PI plenum, be enough? Keeping it simple, Sir! An equally simple switch on the throttle pedal to turn it on and squirt continuously until the pressure came off the throttle. It might even run off the PI pump. John, just thinking aloud. John, Fully agree on keep it simple, providing it will work. The auxilliary petrol distribution between cylinders might be the problem. In a conventional setup little fuel normally evaporates before the inlet valve, and most of the droplets volume evaporate in the heat of the compression stroke.** So there's a wet fuel distribution problem. I have been looking into manifold water injection as my pistons will depend upon it utterly at >4psi boost. It turns out that it is extremely difficult to get all cylinders seeing the same flow. Droplets bigger than about 0.5thou diameter just will not go round 90 bends bends. And most low pressure hydraulic injectors wont atomise a large percentage to 0.5 thou diameter. So I suspect that a single acceleration enrichment Lucas injector fed continously for say two seconds after wot ( timer switch?) and spraying into the entry to the plenum might leave the front cylinders still pinking. Maybe one pointing down each pair of intakes - but that might be way too rich For water I am looking into using fogging nozzles , which use impingement to create a fog with about 25% of the volume flow as 1 thou droplets: http://www.bete.com.tw/product/26.pdf At 7bar the smallest nozzle might give suitable flow, although it may bog over-rich if the rpm are too low. It may well be simpler to retard the spark transiently just enough to kill the pinking.... Peter ** Boiling points of alcohols and distillation curve of gasoline http://www.iea-amf.org/app/webroot/files/image/fuel%20info/Butanol/Butanol_figure5.jpg Edited December 11, 2015 by Peter Cobbold Quote Link to post Share on other sites
john.r.davies Posted December 11, 2015 Report Share Posted December 11, 2015 Yes! Many vintage cars would have mechanical retard controls on the dashboard/steering wheel, that pulled a lever to turn the distributor. Like this 1935 Riley: I think that then the purpose was not to have your wrist broken as the spark came in BTDC. But a flick of the lever before you went for the overtake? John Quote Link to post Share on other sites
Peter Cobbold Posted December 11, 2015 Report Share Posted December 11, 2015 I was thinking a solenoid to tug the points a mm or two anticlockwise, triggered by a pedal swtich to sense wot and switched off after 2 seconds with a timer relay. Solenoid replaces the micrometer adjuster. Quote Link to post Share on other sites
TR674 Posted December 16, 2015 Author Report Share Posted December 16, 2015 I gave the tank a dose of valve saver juice, and pump seems to be making usual sounds at usual levels. Thanks all. This topic seems to have become very technical.....??? Quote Link to post Share on other sites
Nick Jones Posted December 16, 2015 Report Share Posted December 16, 2015 Hi Peter, the only carb 6-pots above 9.0:1 that I can bring to mind were the GT6 and 2000 at 9.25, both of which preferred 5 star to 4 star . . . . at least on their specified timing back in the day. Cheers Alec Mk 1 GT6 and Vitesse 2L were 9.5:1, Mk2 9.25:1 as you say. My fiddling with engine management (not a very fair comparison I'll acknowledge) shows that the basic mechanical bits can handle those CRs even with 95 octane, no bother. My Vitesse has run Stromberg 150CDs, SU HIF4s and homebrewed multipoint injection with exactly the same engine and clockwork distributor. On either carb type it pinked on 95 octane, but still ran better than it did on LRP (remember that dishwater?). I did modify the distributor advance curve and change the vacuum capsule which helped but did not cure. The multipoint injection cured the pinking instantly and in fact made it possible to advance the ignition without pinking. I did later add distributorless ignition which gave another step change and allowed me to run more advance that the original ST curve without any pinking at all. What I think this shows is that the standard manifolding gave uneven fuel distribution and this was the major contributor to the pinking, with the more accurate overall fuelling control also helping. Obviously not an issue with PI as regards distribution (when throttle balance is correctly set !) but fuelling accuracy is not always so good. On the final version of my 2.5 PI, also with EFI and distributorless ignition, I was running 10.25:1 CR. This because when I did the head I intended to run a more aggressive cam than standard, which needed the higher CR to work to its best. When I dropped that idea and went back to the standard 308778 (132bhp) cam, I knew I was pushing my luck and indeed it was difficult to prevent some pinking in warm weather when using 95 octane, but it was fine on 98. That engine showed a peak of 146 bhp on the rolling road and a near flat torque curve at over 150 lb/ft from 1,800 - 5,200 rpm. I was pretty happy with that - it was (and hopefully still is) a properly fast car. Note that those figures were on 95 octane, but it was a cool day! I've come through this experience with increased respect for the basic Triumph engine design which responds well to a bit of semi-modern tech! Nick Quote Link to post Share on other sites
Andy Moltu Posted December 24, 2015 Report Share Posted December 24, 2015 Alec, A agree about the low compression heads. But disagree about the 9.5 heads themselves needing high octane.The carb 9.5:1 engines run fine on 95RON. I run 8.5:1 compression with 16BTDC static, standard c/f swing and 6 psi boost, making an effective CR around 10:1 and it doesn't pink on 95RON. The reason the PI engines can need high octane is the PI itself and specifically its lack of acceleration enrichment. I found this explanation in Richard Stone's textbook ** Sudden wotting the throttle leds to slow fuel evaporation and a significant percentage wets the manifold and flows only slowly to the inlet valve. The lighter components evaporate off the walls during liquid flow, but these are the low octane hydrocarbons. The good stuff - the less volatile aromatics- stay in the liquid film and take a second or so to flow to the inlets and during that time the engine can knock. The quick and easy cure is high octane fuel, which the engine only needs for second or two after wot. The engineering cure would be a 'throttle pump' type of transient enrichment, that defeated Lucas.Richer mixture burn slower and kill the pinking. ** https://books.google.co.uk/books?id=afYcBQAAQBAJ&pg=PA60&lpg=PA60&dq=manifold+fractionation+%2B+%22+Richard+Stone%22&source=bl&ots=CjVuq0-vGQ&sig=VbdfPnnOlB3NEwbrjU2LIRyPPxU&hl=en&sa=X&ved=0ahUKEwj3-ffUiNLJAhVM0hoKHfpnC6oQ6AEIIjAB#v=onepage&q=manifold%20fractionation%20%2B%20%22%20Richard%20Stone%22&f=false Peter Wasn't the lack of enrichment more a financial compromise than an engineering issue? A lot of corners were cut to get the PI system down to price for Triumph. The fuel pump itself was a compromise, using a wiper motor rather than the unit that Lucas wanted to use. Quote Link to post Share on other sites
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