Thanks Jack and Robin.
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During my engine starting trials I noticed that my very expensive brand new Bosch '044' high performance fuel pump was very noisy. It sounded like it was straining to pump enough fuel through the system. Looking at the pump's spec I feared I had over spec'd the pump as it is rated at 285 litres/hour whereas the Ford lift pump is rated at only 120 litres/hour. Clearly a poor mismatch and a silly mistake.
Here is a picture of the Ford in-tank lift pump.
BMW Fuel Pump trial by
Sabrebuilder, on Flickr
Now I remembered that Mike Garner who built a Marlin Cabrio a few years back had suffered with a noisy HP pump so I asked Mike to comment. As the Granada fuel tank has a built in sump Mike suggested ditching the external Bosch pump altogether and using a BMW HP pump in the tank.
I really liked the simplicity of this idea so bought a used BMW pump to see if it would fit in the Granada tank unit. (I had to buy another BMW pump as my original donor car's one was sold long ago)
BMW Fuel Pump trial by
Sabrebuilder, on Flickr
Comparing the two pumps It certainly looked feasible so it didn't take me long to remove both pumps. The BMW HP pump is about 4cm diameter and 12 cm long and a bit bigger than the Ford lift pump.
BMW Fuel Pump trial by
Sabrebuilder, on Flickr
The BMW pump neatly fits in the Ford pump support cradle but is just a few mm to long.
BMW Fuel Pump trial by
Sabrebuilder, on Flickr
So I used my mini tube cutter to remove a short piece of the steel feed pipe. I used a new piece of suitable rubber hose as the old Ford hose had been softened and swelled by the fuel.
BMW Fuel Pump trial by
Sabrebuilder, on Flickr
Here's the BMW HP pump fitted and connected with a short piece of 'in-tank' compatible fuel hose.
BMW fuel pump in Ford unit by
Sabrebuilder, on Flickr
The result is everything seems to run fine. I've only run the engine for about 10 minutes but no issues.
I need to run a thicker cable from the fuel pump relay to the pump in the boot as the Sabre loom is only 1.0mm (BMW loom is spec'd at 2.5mm) and I’m going to remove the LP pre-filter as it is no longer required. I’ll also have to put an extra couple of p-clips on the hoses where I’ve bypassed the filter and the external HP pump.
Thanks again to Mike for such an elegant solution and probably more reliable as the pump exactly matches the BMW design and engine requirements.
I just wish I’d thought of it at the outset! 😊
It's been a 're-work' week rather than progress but I'm really happy with this solution.
...peter
P.S. anybody want to buy a very slightly used Bosch 044 HP pump??
