Intank Fuel Pumps

ade75 · 24th November 2010, 10:31

Could anyone tell me if the intank pumps for the petrol and diesel models are compatible? I realise the configuration/set up may differ but what about the actual pump itself?

EnEnGee · 24th November 2010, 12:00

They are certainly different part numbers which suggests they are incompatible, and I think the way the fuel is collected and "swirled" round the tank is different. The petrol unit has an integral filter mounted to the assembly, whilst the diesel filter is 'neath bonnet. As to the motor and rotating bits, I couldn't say 100%, but I think the diesel delivery pressure is higher than the petrol.

T-Cut · 24th November 2010, 13:21

The petrol and diesel pumps aren't interchangeable. If you need a new diesel pump, this place is very well recommended: http://www.mkon.co.uk/apps/webstore/...ts/show/948874

TC

ade75 · 27th November 2010, 16:21

Intank pump is not part of the fuel delivery system, it merely keeps the fuel leveloft both chambers of the tank at an even level, therefore preventing fuel starvation to the ub pump. I have discarded my intank pump but have fitted a 'T' piece to the end of the suction pipe from the ub pump with a length of pipe into each chamber of the fuel tank, his prevents the risk of fuel starvation when tank runs low. Seems to have done the trick as I have been running for the past few days with very little fuel in tank (low fuel light on) only topping up £5 at a time, covered over 200 miles with no issues.
Saved myself at least £90 for new pump, or £150 for complete unit. plus peace of mind that there ain't no intank pump to cause problems in the future.
May be a bit premature to assume all is fine, but will post if I have a problem in the future.

stux99 · 27th November 2010, 16:29

I just fitted in-tank pump from mkon, good price and service, comprehensive instructions included.

HarryM1BYT · 27th November 2010, 16:34

Quote:

Originally Posted by ade75

Intank pump is not part of the fuel delivery system, it merely keeps the fuel leveloft both chambers of the tank at an even level, therefore preventing fuel starvation to the ub pump.

Not suggesting you are wrong for one minute, but on later cars they did away with the UB pump, so unless the tank pump is of a different design, the pump must provide some flow to the front HP pump.

T-Cut · 27th November 2010, 19:12

Quote:

Originally Posted by ade75

Intank pump is not part of the fuel delivery system, it merely keeps the fuel leveloft both chambers of the tank at an even level, therefore preventing fuel starvation to the ub pump.

That wouldn't explain why many diesels with a failed in-tank pump won't start/run even when the tank is full. The under-bonnet pump in the early system cannot lift fuel efficiently from the tank to bonnet level. It has to be primed by the other pump. Later systems use a stronger lift pump u/b and dispense with the one in the tank. Your modification may not last as long as you hope since the paired pumps usually fail after a similar period. Does it lift OK when the tank's getting very low?

TC

steveharvey2001 · 27th November 2010, 21:04

Quote:

Originally Posted by T-Cut

Later systems use a stronger lift pump u/b and dispense with the one in the tank.
TC

Are you sure - I thought it was the other way round - with later models dispensing with the one under bonnet ?

Thomas · 27th November 2010, 21:05

Quote:

Originally Posted by steveharvey2001

Are you sure - I thought it was the other way round - with later models dispensing with the one under bonnet ?

Thats correct the one under the bonnet was done away with

ade75 · 28th November 2010, 15:36

Quote:

Originally Posted by T-Cut

That wouldn't explain why many diesels with a failed in-tank pump won't start/run even when the tank is full. The under-bonnet pump in the early system cannot lift fuel efficiently from the tank to bonnet level. It has to be primed by the other pump. Later systems use a stronger lift pump u/b and dispense with the one in the tank. Your modification may not last as long as you hope since the paired pumps usually fail after a similar period. Does it lift OK when the tank's getting very low?

TC

I can assure you that the intank pump is purely acting as a circulatory pump solely within the tank and is not connected by any means to the pick-up pipe from the UB pump.

24th November 2010, 10:31	#1
ade75 Newbie rover 75 classic cdt se Join Date: Jan 2009 Location: Pembrey Posts: 28 Thanks: 0 Thanked 0 Times in 0 Posts	Intank Fuel Pumps Could anyone tell me if the intank pumps for the petrol and diesel models are compatible? I realise the configuration/set up may differ but what about the actual pump itself?

27th November 2010, 16:29	#5
stux99 Posted a thing or two MG3/TF Spark/ MGTF Steppy/ MG GS Join Date: Dec 2007 Location: Wincanton,Somerset Posts: 1,073 Thanks: 6 Thanked 9 Times in 7 Posts	I just fitted in-tank pump from mkon, good price and service, comprehensive instructions included. __________________ [SIGPIC][/SIGPIC]

24th November 2010, 12:00	#2
EnEnGee Posted a thing or two CDT Tourer (SORN) & 2.0 V6 Saloon Join Date: Nov 2006 Location: Sittingbourne Posts: 1,058 Thanks: 2 Thanked 11 Times in 8 Posts	They are certainly different part numbers which suggests they are incompatible, and I think the way the fuel is collected and "swirled" round the tank is different. The petrol unit has an integral filter mounted to the assembly, whilst the diesel filter is 'neath bonnet. As to the motor and rotating bits, I couldn't say 100%, but I think the diesel delivery pressure is higher than the petrol.

24th November 2010, 13:21	#3
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,752 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	The petrol and diesel pumps aren't interchangeable. If you need a new diesel pump, this place is very well recommended: http://www.mkon.co.uk/apps/webstore/...ts/show/948874 TC

27th November 2010, 16:21	#4
ade75 Newbie rover 75 classic cdt se Join Date: Jan 2009 Location: Pembrey Posts: 28 Thanks: 0 Thanked 0 Times in 0 Posts	Intank pump is not part of the fuel delivery system, it merely keeps the fuel leveloft both chambers of the tank at an even level, therefore preventing fuel starvation to the ub pump. I have discarded my intank pump but have fitted a 'T' piece to the end of the suction pipe from the ub pump with a length of pipe into each chamber of the fuel tank, his prevents the risk of fuel starvation when tank runs low. Seems to have done the trick as I have been running for the past few days with very little fuel in tank (low fuel light on) only topping up £5 at a time, covered over 200 miles with no issues. Saved myself at least £90 for new pump, or £150 for complete unit. plus peace of mind that there ain't no intank pump to cause problems in the future. May be a bit premature to assume all is fine, but will post if I have a problem in the future.