New fuel pump or not?

[tfoss]

Back to an age old problem. I've owned my TR since last June. It ran all last summer on short runs up to about an hour or so without a problem. It has an original pump with a cooler and I kept the tank half full. This weekend it died after about 2 hours fairly hard driving ( my wife was not with me ) and brought back memories of the problems I had many years ago with my TR5 which I solved by drilling some ventilation in the wheel arch - problem solved. If the pump is now going to start playing up I would welcome some thoughts upon changing it for the Bosch pump and how difficult it is to fit bearing in mind I'm a solicitor who does know one end of a spanner from the other but am a bit wary about the electrics. Is there any preferance in the supplier (Revington or Prestige). Dont hold my profession against me, everyone is entitled to some fun.

Tony.

[Andy Moltu]

I would go for Bosch - the Lucas pumps were marginal for the job in the first place and the Bosch pump is significantly cheaper.

You could go for one of the kits from the companies you suggested, however it will be a lot cheaper  to get the pump directly from a Bosch agent. (pump part no 0 580 254 909)(

You would also need to get a high pressure fuel line made to fit the Bosch pump at one end) Any good hydraulic company will do this - Pirtek for example.

Then all you have to do is knock up a bracket and connect the fuel pipes.

You can go the whole hog and dispense with the Lucas filter and put a modern filter on the high pressure side (Fram G5311) again the hydraulic company will knock up the link pipe for a few quid. These and other Bosch alternatives can be found on this page and diagrams & photos courtesy of Thomas Kopka

The wiring is the same for the Lucas & Bosch set up although many would advise connecting the Lucas & Bosch pumps with thicker wire than standard +/- a relay.

[tim_trinda]

Tony

 

Have a look at this previous topic on the subject of fuel pumps, you will find both sides of the argue here!

 

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Tim

[JohnC]

The wiring is the same for the Lucas & Bosch set up although many would advise connecting the Lucas & Bosch pumps with thicker wire than standard +/- a relay.

I'm in this camp. By coincidence, I had my Bosch pump on a test rig at the weekend. It was happily meeting flow targets, even at about 130psi, but it does draw more current than the Lucas pump. At 110psi, the current draw was 10A, compared with the factory spec of 5.5A (I think) for the Lucas pump.

 

Having said that, I have had the Bosch pump for 15 years (thanks Enginuity ), and the only problem I've had until recently was the ignition switch melting many years ago. Almost certainly a poor contact causing overheating, but to prevent it happening again I installed a relay which takes its main power from the unswitched supply.

 

I have just had an elusive problem, which prompted me to check the voltage at the pump (as well as getting the pump onto a flow bench). It turned out that the pump was getting only 11-12V, even with the engine running, and hence was both drawing more current and delivering less pressure. I've solved that by running a fat cable from the fuse box to the relay, and thence to the pump. I may relocate the relay to the boot at some stage, which would then allow me to fit an unobtrusive anti-theft switch in the cabin en route (don't want to put a switch in my nice fat cable).

[john.r.davies]

Tony,

I'm in the middle of converting to Pi, and the Lucas pump I bought as NOS (Original box, original seals on connectors) is not up to it.   Don't know why but after a few miles, or warming up, the pressure falls and the PRV starts to oscillate.  So I'm going for a Bosch.

On supplier, I haven't talked to Revington, but Malcolm Jones at Prestige is most knowledgable and helpful.   We are in the middle of an email/'phone discussion on how to achieve what I want.   Talk to him and to Revington and consider your own verdict, M'lud!

John

[tfoss]

Thanks everyone for your help. I've gone for the Revington set up on the basis that they are not too far away if it goes wrong

Tony

[Richard Crawley]

Don't know why but after a few miles, or warming up, the pressure falls and the PRV starts to oscillate.

I recently cured a similar problem on my restored 6; it was OK when cold but as soon as it warmed up, it would start to play up with very bad throttle response. After much investigative work, checks & elimination, I figured it could only be low fuel line pressure. The whole PI system was new (reconditioned) & I had assumed that the PVR blow off pressure had been correctly set on a test rig but the fuel line pressure, when hot, turned out to be only around 90psi. Adjusting the PRV has cured it; so, even if you’ve fitted a new (recon) PRV don’t assume that the fuel line pressure is correct, the only way to be sure is check it.

I would add that I am still a fan of the original Lucas pump, it served me well for 15 years in the 70’s & 80’s without any cavitation problems or the need to carry packs of  frozen peas! I found the trick is to keep it in good condition with annual servicing & reface the gear face plates if they get too scored, this causes internal leakage & the influences the pump capacity/pressure enormously.