Fuel pumps and swirl pots

mcramsay · #1 29th January 2014, 17:35

Just a quick one, where have people mounted swirlpots and fuel pumps in the sportster? Was thinking of hiding a crafty 1 litre pot in the boot and then paneling it off so it can't be seen

morris · #2 29th January 2014, 19:12

All my fuel related stuff is here

http://www.flickr.com/photos/5806804...7629422472628/
There's a drawing in there that shows the layout I used but the wiring is different to what I did in the end. I still haven't got round to fitting an inertia switch either. I stuck my swirl pot as high as possible with a large bore feed down to the injection pump to try an guarantee it never ran dry

The swirl pot needs to go up in the engine bay as close to the feed to the fuel rail as possible really to act as a header for your main injection pump (assuming you haven't got a sump fitted in the main tank in which case you don't need it at all).

is the 5 series Sportster tank baffled?

mcramsay · #3 29th January 2014, 19:18

I can't see it matters where it goes, as long as the injection pump has a good gravity feed From the pot. I had a look tonight, and I think I am going to mount the pot in the engine bay battery compartment, as I'm going to fit a small but powerful race battery in the boot. I should have more than enough room to fit the swirl pot and expansion tank in the battery tray compartment in the centre of the engine bay. That way I should be able to mount the main injection pump lower down in the engine bay. I am assuming that bmw inlet and fuel rails are on the passenger side of the car?

mcramsay · #4 29th January 2014, 19:20

And for tank baffles, I think cammy found out that hard way that his was... By drilling through a baffle to fit the sender unit. However mark said to me that they no longer baffle the tanks, and a shoved a bit of welding rod in the filler hole on the tank and could not feel any baffles, but I will stick an endoscope in the tank and have a look just to be sure

morris · #5 29th January 2014, 19:56

is your engine an M50? if so the metal pipes that feed and return from the rail are clipped up under the intake manifold and poke down just by the throttle body. feed goes in at the front of the engine end and out via the pressure regulator at the rear end.

I'm not sure about the M52 but on my M54 in my 325, I think that both the feed and return come in at the rear of the rail and the pressure regulator is part of the fuel filter (just to make it really expensive to change).

Cammy · #6 3rd February 2014, 11:14

Craig,
Both of the M52 engines I have are the same regarding the fuel rail setup on the passenger side of the car. I am planning on connecting to the hose sections that are still attached to the rail with a couple of hose joiners. I will connect these to the HP pump in the engine bay with the return line going, via another joiner straight down the tunnel - the tunnel sections being copper pipe.

I have decided to drop the swirl pot after discovering the hard way, as you said, that my fuel tank most definitely does has baffles. Up to that point I was going to put it in the battery compartment.

What kind of battery are you thinking about? There is quite a bit of info in the forum on what other builders have used but I am also thinking about putting mine in the back of the car and was looking at the Powervamp series.

Cheers

Cammy

MartinClan · #7 3rd February 2014, 12:31

Cammy - are you aware that modern petrol with its high ethanol content corrodes copper? I am not sure how serious it is but there is plenty of discussion some of the classic car sites about it.

Robin

Mike · #8 3rd February 2014, 19:44

Quote:

Originally Posted by morris

is your engine an M50? if so the metal pipes that feed and return from the rail are clipped up under the intake manifold and poke down just by the throttle body. feed goes in at the front of the engine end and out via the pressure regulator at the rear end.

I'm not sure about the M52 but on my M54 in my 325, I think that both the feed and return come in at the rear of the rail and the pressure regulator is part of the fuel filter (just to make it really expensive to change).

Hi Ian

The M54 does not have a return flow to tank. It has a pressure regulator valve in the filter before the rail. Its to reduce vapourisation of the fuel.

Cammy · #9 3rd February 2014, 20:14

Hi Mike,

Thanks for the heads up. I had heard and read a bit on the issues with modern fuel and have been considering an alternative. Good prompt to dig into the latest options on this as the last time I looked there was nothing conclusive regarding the options with rubber hoses.

Happy to hear anyones views on this and advice on alternatives?

Cheers

Cammy