JohnD Posted May 9, 2015 Share Posted May 9, 2015 My Pi system that has a Bosch pump has been laid up for a year while I built a new engine. Now it's all back together, the fuel pressure is only about 75psi. Apart from the Meter unit, which was off and on again as the engines were changed, I haven't disturbed the Fuel system. A non-Triumph technician who knows Bosch in Fords etc. says that a long layup can sieze the pump. The ball bearings that act as vanes will not rise from their recesses eniugh and the pump just turns. Anyone met this before? Any ideas, apart from 'a new pump'? I've thought of running fuel treated with Redex - but which type, cleaner or 'upper cylinder lubricant' - or two stroke oil, through the pump, round and round from a can. Anything else that might free it up? JOhn Link to comment Share on other sites More sharing options...
esxefi Posted May 9, 2015 Share Posted May 9, 2015 could try running a closed loop of diesel to see if it frees anything up. but once an efi pump goes off pressure it may not recover fully. Link to comment Share on other sites More sharing options...
Triumph-V8 Posted May 10, 2015 Share Posted May 10, 2015 I would have a look at the pressure valve. If nothing comes out of the overfuel line back to the tank the pump is suspect, otherwise if fuel runs maybe the valve sticks. Link to comment Share on other sites More sharing options...
Nick Jones Posted May 10, 2015 Share Posted May 10, 2015 I think the main points have been covered above. If you are getting fuel back through the PRV it would suggest the fault lies there, if not, the pump is sick. Is it making odd noises? If so I'd be taking a close look at suction pipework and any filters/strainers on the suction side. If pump runs quietly, but at reduced flow/pressure then it would appear your technician contact may be onto something - though I've never had this issue myself (having returned a number of scrapyard-sourced Bosch roller cell pumps to service). I'd be inclined to try a recirculation loop of petrol dosed with fuel system cleaner at fairly high concentration - Toolstation do a cheap one that seems to be effective. Good luck..... Nick Link to comment Share on other sites More sharing options...
JohnD Posted May 10, 2015 Author Share Posted May 10, 2015 (edited) Now here's a funny thing. It may not be the Bosch pump, but the Facet lifter pump! Forgive the long explanation, please... My system has a Facet Gold top that keeps a swirl pot full. The Bosch pump draws guaranteed air-free fuel from the bottom of the pot. The idea - and the fact - was to prevent the Bosch sucking air on a less than full and surging main tank. It worked, before. Thinking (as above) that it might be the PRV, I disconnected the return from that to the tank. Copious flow - BUT FULL OF BUBBLES! So I disconnected the hose from Bosch to PRV, to see about that - LOTS of bubbles! Air was getting into the flow, but where? After that, running only the Facet lifter, it took some time the fill the swirl pot before flow back to the tank recommenced. The Facet just isn't keeping the pot full, and air is reversing up the return tube to the main tank and into the Bosch. So, out with the Facet, and let's have a look. And this brings up my next request - does anyone have a diagram of the assembly of a Facet? Anyone who has done so will know that inside is a filter, and in the middle the top of the pump mechanism, with a spring clip holding it together. But there was an O-ring under the spring clip, with one edge caught in the valve. Not a 'correct' position. Where should that O-ring be? I can't find a diagram of the assembly of the pump anywhere on the 'net. Do you have one, please? JOhn PS Reassembled Facet without the O-ring, put it all back - and it works! Full 100psi! So the O-ring was the problem, making the valve in the Facet ineffective, and reducing the flow to the Swirl pot. But where did the O-ring come from??? Edited May 10, 2015 by JohnD Link to comment Share on other sites More sharing options...
Nick Jones Posted May 10, 2015 Share Posted May 10, 2015 Perhaps the O ring was never part of the Facet but a foreign body - or was it downstream of a strainer? So long as it all works!! Nick Link to comment Share on other sites More sharing options...
JohnD Posted May 11, 2015 Author Share Posted May 11, 2015 Used to have a tank-to-Facet filter, one of those glass-bodied, cleanable ones, but the glass tube cracked. And a Facet has a fine filter inside it before the pump. No way the O-ring could get through that!. I'm still stumped about where the O came from or where it should be. Going for another first start today. JOhn Link to comment Share on other sites More sharing options...
Nick Jones Posted May 11, 2015 Share Posted May 11, 2015 Good luck with that! I also have one looming hopefully, though still some days off...... Nick Link to comment Share on other sites More sharing options...
JohnD Posted May 11, 2015 Author Share Posted May 11, 2015 Doh! the O-ring lives under the washer, over the valve! I can only presume that it wasn't a Viton one and got distorted by modern fuel. Correcting that - you have to order small Viton O-rings! But I've replaced it temporarily with an ordinary one, and found that the Facet flow is still much less than advertised. A red-top should deliver 150 L/h. I collected a glassful - 300mls in 15 seconds, that's 1200mls a minute, or 72 L/hour. It should be twice as much. Some Bosch pumps can deliver 158 L/h at 100psi! Don't know the exact spec of this one, but no wonder the Facet can't keep up, and the swirl pot empties. I'm still v.puzzled - this system worked well, before. JOhn Link to comment Share on other sites More sharing options...
josh18 Posted May 18, 2015 Share Posted May 18, 2015 Hey John, I have had a similar problem and come to a similar conclusion with my setup, which was similar to yours. I looked up the specs of my boost pump and forund that it was not enough L/H to supply the bosch pump at high fuel demand. I have now removed the boost pump and swirl pot and replaced the tank outlet line to the bosch pump with half inch tube, including the tank outlet. This seems as good or better than before, even without the boost pump, though I haven't run the tank down to see how bad the surge is. Link to comment Share on other sites More sharing options...
JohnD Posted May 18, 2015 Author Share Posted May 18, 2015 I may have mislead myself by running the Bosch pump with absolutely no post pump resistance, staight back into the tank. Or, I may have needed the Viton O-ring that is now fitted. Any road up, I put it all back together, and Lo! 102 psi! And a prompt engine start! I now have 5 L of fuel in can, with ten times as much Redex injector cleaner as prescribed and twice as much two stoke oil. Never mind - the lawnmower will swallow it. Thanks to all for suggestions - it's good to tawk, innit! John Link to comment Share on other sites More sharing options...
Nick Jones Posted May 18, 2015 Share Posted May 18, 2015 Glad to hear it's all working again! Good ol' lawnmower the fuel dustbin......... Mine too. Ancient Honda flat-head which has run on diesel (accidental), E85 (intentional using up of the consequences of a Vitesse misfuel) and now some ancient stuff left in our garage by the PO which smells like old white spirit and looks like wee. It may in fact be ancient heating oil (kerosene) and it's really not very flammable. Needs to be heavily diluted with the proper stuff and even then a dash of carb cleaner is needed to start it! Nick Link to comment Share on other sites More sharing options...
JohnD Posted May 19, 2015 Author Share Posted May 19, 2015 (edited) There are different schools of thought on the disposal of old, stale fuel. There is the Happy Hippy Way: The Miniature WMD Way: The Red Neck Way: and the Air Head Way: particularly effective when you fight the resulting fire with a water hose! Me, I'll use the Lawn Mower Way. John Edited May 19, 2015 by JohnD Link to comment Share on other sites More sharing options...
JohnD Posted March 25, 2016 Author Share Posted March 25, 2016 Just to bring you-all up to date, the above was not the end of the story. Started driving the car, even commuting in it, so now have a thousand miles on the new engine. And I'm disappointed with it; it just hasn't got what I expected, even allowing for 2L when it had 2.5 before. AND, the fuel pressure isn't holding up. Idling, and well warmed up, it can reach high 90s, but on the road, and under hard acceleration, it drops to the 60s. Can barely get to 70mph. Frankly, my dears, I'm surprised that it even runs at that pressure. To test if the PRV was at fault I adjusted it (I have one of Prestige's easy-adjust ones) and got a steady 102psi (top of scale on my digital gauge) but it still fell to 70-odd when the pedal met the metal, so the fuelling problem was still there. So, I bit the bullet and fitted a new high pressure fuel pump. And it is transformed! The torque is up, and it's still accelerating hard as we go to LightSpeed and through the 70mph barrier. WooHoo! I can't test it any further on the public road, but I'm entered for the CSCC meeting at Snett on April 10th, so we'll see there. The moral is, if you have Pi don't leave it laid up with ordinary, modern fuel for any length of time! It is known to be hygroscopic and the water absorbed must have cause corrosion in the pump, making some/all of the ball bearings ineffective. My lay up was longer than just over-winter, but next winter, I want to put something in the fuel to stop this. Any recommendations? Millers "Tank Safe"? Briggs & Stratton "FuelFit"? They are garden mower makers so should know about occasional use and winter layup Stabil Storage Fuel Stabiliser? Etc. John Link to comment Share on other sites More sharing options...
Nick Jones Posted March 25, 2016 Share Posted March 25, 2016 Don't know about the fuel stabilisers John - I prefer to try and use the car often enough to stop the fuel going off, though I realise that isn't always possible. Thanks for the update on the pump situation - interesting and useful to know. Perhaps a contributing factor is that the Bosch pump is not really intended for PI fuel pressures (K-Jet operates at 75 psi) so even though it is rated to 120psi (where an internal relief valve opens) running continuously at 105psi is working it quite hard. And this assumes that it is a Bosch pump designed for the mechanical K-jet system as the very similar looking EFI pumps are designed to run at much lower pressures. If you are curious enough it is possible to take these apart (and maybe even re-assemble if you are very careful undoing the crimp in the can) to carry out a PM...... I've been known to run them backwards and even wack them on the bench to unstick them - which does usually work. Something else that might be worth checking out is that most proper Bosch pumps have an internal inlet strainer and in the OE applications that tends to be the only filtration on the inlet side. These can and do clog up - which is troublesome as they cannot be accessed for cleaning. You can probably ignore this if you gave a pre-filter. Nick Link to comment Share on other sites More sharing options...
JohnD Posted March 25, 2016 Author Share Posted March 25, 2016 This was, and the new one is, a Prestige kit installation. Malcolm provides a pre-pump filter. My initial 'cure' was to run a high concentration of injector cleaner around the tank-pump-tank circuit. as said, it seemed to work for a while, so I assumed fuel gluey bits had gummed it up, but as related, it didn't keep getting better. And I had fitted a new pre-filter element. I will do a Post-Mortem. Is undoing the crimp done by gentle use of pliers? JOhn Link to comment Share on other sites More sharing options...
GP2.5 Posted March 26, 2016 Share Posted March 26, 2016 Hello, Before layup run the engine with alkylat petrol, the purest and most stable fuel you can get. I assume that the Briggs and Straton fuel is an alkylat. I have two cars with mec-injection and they rest the winter out with alkylat fuel in thier venes. Also a cog wheel pump - just as the original Lucas - is not as sensative to clogging as the Bosch pumps are, an alternative to Bosch is a Pierburg, a cog wheel pump superior to all Bosch pumps. Gunnar. Link to comment Share on other sites More sharing options...
JohnD Posted March 27, 2016 Author Share Posted March 27, 2016 (edited) Alkylate petrol? I can find only one company that sells it, and their blurb is just fruitloopery. "Environmental petrol" ??? "When you use Aspen environmental petrol, you avoid dangerous substances such as benzene and aromatic hydrocarbons, substances that can cause serious health problems. The engine is also treated more kindly, for example, the spark plug and combustion chamber are kept cleaner. As Aspen is also ethanol free, the petrol can be stored safely and even after long periods of no use, your engine starts without any problems if your tank has been filled with Aspen environmental petrol. Environmentally, there are numerous benefits, e.g. the formation of ground-level ozone (smog) is reduced by more than 50%." At nearly £4 a litre and only in 5 L containers, it would have to be God Juice before I'd use it, even on my precious race engine. It claims to be ethanol-free, which I think is the source of my problems, so I'd rather buy some 'preservative' to keep that absorbed water in suspension. Marine users are probably most at risk, and I found this "Which?" style report from US "Boating" magazine: http://www.boatingmag.com/gear/boatinglab-tests-fuel-stabilizers I think only 'Stabil' is available in the UK, and they found them all equally effective, but very different in price and the advertised duration of action. So I'm inclined to buy whatever is available here, is cheap and offers the longest effect. Any other views? John Edited March 27, 2016 by JohnD Link to comment Share on other sites More sharing options...
Nick Jones Posted March 27, 2016 Share Posted March 27, 2016 Wouldn't argue with your logic John. Nick Link to comment Share on other sites More sharing options...
GP2.5 Posted March 27, 2016 Share Posted March 27, 2016 Well, You would only need one 5 litre container for a car resting over the vinter. I have tested to evaporate ordinary 98 octane and alkylat fuel, 98 octane blures a glas bowl. When evaporated with alkylat there is no blure on the surface of the glas. Fuel with etanol will keep water in suspension, fuel without will keep almost no water in suspension. When testing fuel directly from a filling station for water the result is in 19 cases out of 20 nil. and that goes for England as well. Gunnar Link to comment Share on other sites More sharing options...
JohnD Posted March 27, 2016 Author Share Posted March 27, 2016 Gosh, Gunnar, you have been invesigating this! Please tell us more about this test that blurs, or doesn't a glass bowl. I've no doubt that ethanol fuel will hold water in suspension, but there is a limit to how much. The Boating magazine found that it would suddenly form a big drop of water as it came out of suspension, that was the limnit of thier test of the various fuel preservers. John Link to comment Share on other sites More sharing options...
GP2.5 Posted March 28, 2016 Share Posted March 28, 2016 Yes, John, petroleum industri is always testing so is the car industri just as your Minestery Of Transport. My simple test was just filling upp two E- Containers with 3 dl of petrol and let it evaporate in the shed. I did this several years ago when I had an Alfa with Dellortos. they clogged upp during the winter when the petrol evaporated. After 3 winters they gave a lean mixture, very hard to start and spitting back - and was almost impossible to clen out. Sticking shellack like depostit on the jets that would not solve in petrol. Idle/lowspeed jets really clogged. Aceton and a US Ford carburettor cleaning solvet was the best I faund for dissolving. This agony with petrol leaving deposits when evaporating began when the petrol industri started to hard crack the crude oil.. I will do the same simple test with a new petrol just launched in Sweden, it,s partly syntetic about 20% of it,s content comes from processed pine oil. I have heard good about the German Aral petrol -104 octane - its also partly syntetic. I think Germany is the only place you could have it -out of reach for us. I think your problem is deposits after evaporation and the drying, no lube, rubber destroying ethanol. Gunnar Link to comment Share on other sites More sharing options...
JohnD Posted June 13, 2016 Author Share Posted June 13, 2016 (edited) Further, delayed update. I did buy a new Bosch pump from Prestige, and it really did the business. My diagnosis of pump fouled up, either by corrosion or deposits after sitting too long was correct, and my cure, of running the pump in a circle with fule stuffed with injector cleaner was inadequate. A new pump brought the engine to life. But that wasn't the only bit to be fouled up. For my second race of the season, I fiddled with the adjustable PRV. And got no response from the fuel pressure gauge, which had persistently been reading 92ish, with drops to the 70s. turn the adjuster one way or the other, it made no difference. None at all. After another go to raise the pressure between qualifying and race, it read only 62 and then 102! But the Glowshift gauge's range is only up to 102. Then I found this on the Bay: http://www.ebay.co.uk/itm/301046019421?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT It's advertised as, and the dial reads "oil pressure", but the range is up to 120psi, the transducer is exactly the same size as the Glowshift one, and the wiring is simpler. Even better, only £15, a quarter of the Glowshift price. Reader, I fitted it. It showed the actual fuel pressure (if it is to be believed) was 112psi. So I re-adjusted the PRV to 106, and off we go - whoopee! Could a similar problem to the fouled up pump, corrosion or deposits have impaired the Glowshift transducer function? Would operating it above its range have damaged it? Did it get tired? Anyway, Normal Service has now been Restored. I'm all set for the Classic Le Mans, n'est-ce pas? John Edited June 14, 2016 by JohnD Link to comment Share on other sites More sharing options...
pomwah Posted June 14, 2016 Share Posted June 14, 2016 Ooo-la-la, bravo, bravo! Link to comment Share on other sites More sharing options...
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