Lockley210 Posted January 21, 2007 Report Share Posted January 21, 2007 I have recently fitted a Bosch 044 pump and it has cured the power lag and rough running problems that I was having before, however the PRV valve is making a high pitched whine when I get to approx 3000 rpm. The whole system is like a church mouse at tickover and low engine revs. The only way I can get it to stop is to pinch the return pipe from the valve a little I have a inline pressure guage fitted to the metering unit and its set at 110psi ( Engine running ) Having looked through previous links in the Forum I am assuming the harmonics may be induced as a result of the length of the pipe from the pump or a weak spring to the PRV. Do I experiment with a longer pipe - Replace the PRV - Replace the spring in the PRV ? Has anybody got any ideas ? If not I think it might be a trip to see Malcolm at Prestige. Mark Quote Link to post Share on other sites
preport Posted January 21, 2007 Report Share Posted January 21, 2007 I sorry I don't know the answer to your question, but it answers the noise that mine makes at 1500 rpm. It is not very loud but there none the less. Is it chance that the engine speed it happens on yours is harmonically linked to the speed it happnes on mine? NIck Quote Link to post Share on other sites
Richard Crawley Posted January 21, 2007 Report Share Posted January 21, 2007 I still run the Lucas so don’t have any experience of the pipe harmonics phenomenon that some have experienced. I had a similar on my Lucas system &, in the end, a new PRV was the only cure. You could try giving the PRV a few sharp taps; this sometimes works in the short term but, as experienced with mine, it didn’t seem to cure it permanently. As you have a pressure gauge, I think it’s certainly be worth stripping, cleaning, reseating & resetting the PRV before you start experimenting with pipe lengths & a quick phone call to Malcolm may bring some good advice. Quote Link to post Share on other sites
wheeler Posted January 21, 2007 Report Share Posted January 21, 2007 Hi Mark I too had a lot of noise problems after I replaced the old Lucas pump with a new Bosch pump. Evidently the Bosch pump is not a very good 'sucker' and needs a good head of pressure. Is the pump mounted at the lowest point in the boot spare wheel space? Ideally you need to fit a larger fuel pipe outlet on the tank and larger diameter pipe from tank to input of Bosch pump, make sure there is no 'crud' in the bottom of the tank reducing the flow or partially blocking the outlet/pipe. Also never let the tank go below a quarter full. Finally check the electrical supply to the pump. The pump draws quite a high current and any resistance in the circuit will cause a volt drop at the pump, inertia switch and bullet connectors can give trouble, some owners fit a pump relay and larger diameter wiring (a circuit diagram was recently posted on the forum), is there a good earth to the pump? Hope this helps Best regards Bill PS If all fails do as Richard suggests ring Malcolm at Prestige. Quote Link to post Share on other sites
Lockley210 Posted January 22, 2007 Author Report Share Posted January 22, 2007 Many thanks for your advice, perhaps I should explain the mods that I have carried out so far :- 1.The pump is mounted under the wheel arch on rubber mounts 2.It is supplied with twin rubber fuel pipes, one from the original tank (1/4) outlet via a new filter that has a flow rate of 2.5 Lts/min ( 150L/Hr) 3.The other 10mm (ID) supply is from the modified drain outlet using a bullet high flow filter 4.The high pressure pipe is approx 500mm long, steel braided and wrapped in foam pipe insulation to stop any resonance where it is in contact with the body. 5.The power is via a 30A relay and 30amp rated cable directly from the battery, and the earth is good. When the engine is not running the returm pipe from the metering unit has a small quantity of fuel flowing however this flow stops as soon as I start the engine, is this the norm ? If I reduce the fuel pressure to around 105psi (running) the harmonics start up at a lower engine speed !!! I think I will increase the length of the high pressure pipe and change it to rubber instead of steel braided and order a new PRV from Malcolm. Thanks for the advice ,I will publish the solution (if there is one) as soon as the other arf stops giving me grief over the vast quantities of fuel I have deposited on the garage floor !!! Best Regards Mark Quote Link to post Share on other sites
phil.simo Posted January 27, 2007 Report Share Posted January 27, 2007 Mark I had the same problem with mine when I fitted a bosch pump from Prestige, it sounded like a horn going off in the boot! so I replaced the PRV on Malcolm from said company`s advice but it was just the same, so out of despiration I tried the old rubber high pressure pipe from the pump to the PRV and this was better but the sound returned half a mile down the road on the test run!! As it was a slight improvement, all be it a small one, I recconed maybee a longer rubber hose could do the trick. So a pal of mine had a saloon PI pipe which is about twice as long as the TR one that I tried and that was 3 years ago and the noise has`nt returned :-) my conclusion was that the pulses from the pump had no where to go before the PRV (which is what was making the noise) with the airoquip hose and not enough length for the standard rubber hose. so the longer rubber hose must have enough give in it to absorb the pulses from the bosch pump. hope this helps Phil P.S. the spec of my pipes, wiring and relay`s etc apart from the high pressure pipe is the same as yours. Quote Link to post Share on other sites
Lockley210 Posted January 28, 2007 Author Report Share Posted January 28, 2007 Mark I had the same problem with mine when I fitted a bosch pump from Prestige, it sounded like a horn going off in the boot! so I replaced the PRV on Malcolm from said company`s advice but it was just the same, so out of despiration I tried the old rubber high pressure pipe from the pump to the PRV and this was better but the sound returned half a mile down the road on the test run!! As it was a slight improvement, all be it a small one, I recconed maybee a longer rubber hose could do the trick. So a pal of mine had a saloon PI pipe which is about twice as long as the TR one that I tried and that was 3 years ago and the noise has`nt returned :-) my conclusion was that the pulses from the pump had no where to go before the PRV (which is what was making the noise) with the airoquip hose and not enough length for the standard rubber hose. so the longer rubber hose must have enough give in it to absorb the pulses from the bosch pump. hope this helps Phil P.S. the spec of my pipes, wiring and relay`s etc apart from the high pressure pipe is the same as yours. Quote Link to post Share on other sites
Lockley210 Posted January 28, 2007 Author Report Share Posted January 28, 2007 Oops hit the wrong key !! Phil, Just like you I have fitted the modified PRV valve from Malcolm, and although it has changed the pitch slightly it is still like having an Orchestra in the boot. Malcolm suggested I change the length of the pipe to at least 40 inches , so this is my next task. Did you end up with a similar length of pipe ? Kind Regards Mark Quote Link to post Share on other sites
millsie Posted January 29, 2007 Report Share Posted January 29, 2007 Hi - I don't have the resonance problem with my Bosch pump but want to move it down further into the boot and will need a longer pipe (pump to PRV) - does anyone have supplier details for either a longer pipe assembly or the components to make one to fit ? If Aeroquip or Earls does anyone have the part numbers ? Thanks in advance Dave Quote Link to post Share on other sites
Lockley210 Posted January 29, 2007 Author Report Share Posted January 29, 2007 Hi - I don't have the resonance problem with my Bosch pump but want to move it down further into the boot and will need a longer pipe (pump to PRV) - does anyone have supplier details for either a longer pipe assembly or the components to make one to fit ? If Aeroquip or Earls does anyone have the part numbers ? Thanks in advance Dave Hi Dave I obtained my fuel lines from James Lister http://www.lister.co.uk/ecommerce/response...;act=FRAMESETUP Regards Mark Quote Link to post Share on other sites
phil.simo Posted January 29, 2007 Report Share Posted January 29, 2007 (edited) Mark, Its about 29" long and is the one fitted to the saloon 2.5PI, they are available from rimmer bros, pt. no. 153736 and cost £13.80 inc. VAT With fitting a rubber one it means you dont have a long length of pipe coiled up as you would with the areoquip pipe. Phil Heres a pic of instalation Edited January 30, 2007 by phil.simo Quote Link to post Share on other sites
badshead Posted January 29, 2007 Report Share Posted January 29, 2007 Hi Phil What sort ot pre-filter are you using and where did you get it? Quote Link to post Share on other sites
phil.simo Posted January 29, 2007 Report Share Posted January 29, 2007 Hi Bill, The pre filter came with the bosch kit from Prestige injection, But I have found the same filter on the demon tweeks web site at £50 +vat and they supply the replacement elementd at £3.22+vat. It's a FSE Hi-Flow Motorsport Fuel Filter. Phil demon tweeks link Quote Link to post Share on other sites
RobinTR6 Posted January 30, 2007 Report Share Posted January 30, 2007 Hi Bill, The pre filter came with the bosch kit from Prestige injection, But I have found the same filter on the demon tweeks web site at £50 +vat and they supply the replacement elementd at £3.22+vat. It's a FSE Hi-Flow Motorsport Fuel Filter. Phil demon tweeks link Currently using one pre one post filter from a Fiat Punto, about £10 each and all has been perfect since installation. Advice for pump from the guys who supply the TR distributers with Bosch pumps so they know their stuff. Quote Link to post Share on other sites
Lockley210 Posted January 31, 2007 Author Report Share Posted January 31, 2007 Hi Bill I have also fitted the Bullet filter but thought it a little expensive I have found a similar filter that flows the same on E-Bay - Item number: 280074043886 £13 It off a JCB and looks the same as the original CAV filter but with a clear bowl and stainless steel filter,so you can see the crud before the pump does ! Regards Mark Quote Link to post Share on other sites
Lockley210 Posted February 1, 2007 Author Report Share Posted February 1, 2007 I'm again Had a 2m long rubber hose made , coiled it up and over the tank -- Noise from the PRV has GONE Just been on a very high speed test for 50 miles FANTASTIC Thanks for all your advice Mark Quote Link to post Share on other sites
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