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englishguy1013
12-09-2011, 06:59 PM
hope some one can point me in the right direction with this
88 range rover classic 3.5 the problem have is the fule pump does not seem to be running when i try to start it , have checked all fuses and the main and fuel pump relays i can hear them both click i thought it was the pump so i removed the tank and replaced the tank to find out it was not bad !
should this system prime the fuel system to build up pressure, i have worked on the earlier injection system as fitted to the english classics what when you moved the flap in the airflow meter the pump would run. kinda lost on this one

anyone have any ideas

mearstrae
12-10-2011, 08:01 AM
Check the fuel pressure at the intake fuel rail, a pump running (making noise) doesn't always mean it's actuially pumping, and check the fuel filter for blockage. These are the easiest checks.
My '95 Classic has a schrader valve on the intake fuel rail that (I know it's not recommended...) I checked with an old tire guage wrapped in a rag. Sure enough, the pump was making noise but not pressure, electric fuel pumps are self priming.

'95 R.R. Classic LWB
'76 Series III Hybrid 109
'70 Rover 3500S

mearstrae
12-10-2011, 08:08 AM
Oh, as an after thought... If the White/Green wire on the ign.coil isn't connected (making contact) it won't allow the injectors to turn on. This is on the 14CUX systems and is to prevent flooding in the event of a ignition failure.

'95 R.R. Classic LWB

englishguy1013
12-12-2011, 06:59 PM
i extended the wires in the pump so i could have it near me to see if the pump ran when the key is turned on, but the pump didnt run.

kind of thinking that the relay may not be working correctly

at the worst i might just ditch the injection and replace with new intake and carb !!!!!!!

mearstrae
12-12-2011, 07:31 PM
Try removing the pump and running it staright from the battery (only try to run for a short time as the fuel is a coolant from the pump when it runs...). This will get to the root of the problem, if it's the pump our hosts have a good price on replacements. The change to a carb will be a little pricey and you'll still need a new pump and custom plumbing to hook it up, as well as carb linkage fabrication. If that's the route you choose to take, the Edlebrock Rover/Buick manifold with Edlebrock carb and carter Elec. Fuel pump would be the best way to go. My hybrid runs a Holley with a JWR manifold (Offenhauser 360), my Rover 3500S runs the Edlebrock set up, and is the better of the two.

'95 R.R. Classic LWB
'76 Series III Hybrid 109
'70 Rover 3500S

englishguy1013
02-05-2012, 07:58 PM
ok so i have replaced the injection relay, bypassed the fule filter and fitted complete fuel pump unit from rovers north (very good service) i now have fuel at the fuel rail here is the but......... cranks over then will start but not for long the question i have is should the fuel pressure regulator allow fuel to return to the tank when the pump is priming the system ie engine not turning over as i for some reason have fuel returning to tank when pump primes..... i would thought that the regulator would stop fule returning until the engine runs and let the diafram open with with intake vaccum is this correct or have i got it totally wrong. as it is the rover is on ebay for sale kinda fed up with it .

mearstrae
02-05-2012, 08:17 PM
Rovers are like that...You'll always have a day (or several) when you're fed up (and ready to put a wrench through the windscreen). And usually the problem is a simple one (when you finally hit on the answer). Fuel injection returns fuel to the tank when it reaches the preset pressure, whether starting or running. You might now have fuel but still don't have ignition spark. And there are fuel injector resistors in the system that need to know the engine is running. I had this "Start-Run-Shutdown" situation when I changed to an HEI distributor. It would start everytime and run maybe a minute and then quit. My White/Green wire to the resistors wasn't connected, it only took a few odd days to figure that out.

'95 R.R. Classic LWB
'76 Series III Hybrid 109
'70 Rover 3500S