Diesel lift pump

[MoominPapa]

My Lister FR2 has a day tank, filled by a rotary hand pump. Whilst this is all nice and trad, it has some disadvantages. The pump leaks, it's a pain to use and the only way to check the level in the tank is with a dipstick which is even more of a pain to use.

 

So, I'm wondering about solving the entire problem by ripping it out and replacing it with something like Clicky

 

The current arrangement down stream of the day tank is a fuel cock on the tank outlet, then to a filter/water separator, then a flexible pipe to the engine inlet. The engine has a second (wick type) filter. Injector overspill goes into the filter/water sep via a non-return valve.

 

Questions.

 

1) What pressure should the pump delivery be? The static head from the current day tank calculates to 1-2PSI. Facet make pumps which go that low, but commonly available ones are maybe 5-10PSI. Will it matter if I use one of those?

 

2) Apart from the injector overspill, there's currently no recirculation. The filter has two blanked-off spare ports, one marked as an inlet and one as an outlet. Can I use the outlet as a recirculate line back to the main tank, to avoid the need to bleed the pump and suction line from the tank?

 

3) Any BSS gotchas? I know that I need all metal pipes and connections, and no soldered joints.

 

4) The main diesel tank arrangment is odd: there's both a tank at the stern and one a bilge level. When both are full, the diesel level is about the same height as the engine injectors, when the tank is nearly empty, the lift pump will be lifting from almost base-plate level. Is that likely to cause any problems?

 

Thanks in advance for any suggestions or advice.

 

MP.

[larkshall]

My Lister FR2 has a day tank, filled by a rotary hand pump. Whilst this is all nice and trad, it has some disadvantages. The pump leaks, it's a pain to use and the only way to check the level in the tank is with a dipstick which is even more of a pain to use.

 

So, I'm wondering about solving the entire problem by ripping it out and replacing it with something like Clicky

 

The current arrangement down stream of the day tank is a fuel cock on the tank outlet, then to a filter/water separator, then a flexible pipe to the engine inlet. The engine has a second (wick type) filter. Injector overspill goes into the filter/water sep via a non-return valve.

 

Questions.

 

1) What pressure should the pump delivery be? The static head from the current day tank calculates to 1-2PSI. Facet make pumps which go that low, but commonly available ones are maybe 5-10PSI. Will it matter if I use one of those?

 

2) Apart from the injector overspill, there's currently no recirculation. The filter has two blanked-off spare ports, one marked as an inlet and one as an outlet. Can I use the outlet as a recirculate line back to the main tank, to avoid the need to bleed the pump and suction line from the tank?

 

3) Any BSS gotchas? I know that I need all metal pipes and connections, and no soldered joints.

 

4) The main diesel tank arrangment is odd: there's both a tank at the stern and one a bilge level. When both are full, the diesel level is about the same height as the engine injectors, when the tank is nearly empty, the lift pump will be lifting from almost base-plate level. Is that likely to cause any problems?

 

Thanks in advance for any suggestions or advice.

 

MP.

 

I've used these pumps to lift fuel from lorry tanks to a diesel frezer unit mounted on the cab of 7.5 tonne trucks. They work well with one proviso. If the main tank is allowed to drop to a point where he pump sucks air, and then tank is re-filled, the pump will not lift diesel until the outlet pipe is slackened off to bleed the 'up' pipe. But you are not likely to have that problem, as you won't be lifting to between 8 and 9 feet.

 

In our installation these lift pumps lift to the injector pump of the freezer engine, and there is a gravity return to the tank DAF cargo 45's seem to have the same filter arrangement you describe, and the outlet from the filter does re-circulate to the tank .

 

I guess you will use a float valve in header tank to dictate pump demand?. If so fit a suitable solenoid to protect float valve electrical contacts, a favourite failure point.

[PaulG]

My Lister FR2 has a day tank, filled by a rotary hand pump. Whilst this is all nice and trad, it has some disadvantages.

 

Don't expect me to sympathise. I just covet the FR2.

[MoominPapa]

I guess you will use a float valve in header tank to dictate pump demand?. If so fit a suitable solenoid to protect float valve electrical contacts, a favourite failure point.

The plan was to loose the header/day tank, and feed the engine injection pumps directly from the lift pump. I guess using a float valve and keeping the tank would be a possible alternative.

 

MP.

[ditchcrawler]

The plan was to loose the header/day tank, and feed the engine injection pumps directly from the lift pump. I guess using a float valve and keeping the tank would be a possible alternative.

 

MP.

If you have a suitable overflow line back to your main tank from the day tank then would you still need the float switch/valve. Could you just run the pump all the time the engine is running with any extra fuel returning back to the main tank via the overflow?

[larkshall]

If you have a suitable overflow line back to your main tank from the day tank then would you still need the float switch/valve. Could you just run the pump all the time the engine is running with any extra fuel returning back to the main tank via the overflow?

 

 

Would just be a waste of leccy. I'd keep the day tank for authenticity, just bypass rotary hand pump. Also gives you a bootstrap and braces way of feeding the engine.. This pump would not feed at a high enough pressure directly to the injector pump, to do that you would need something more substantial, like a high pressure diesel pump from a luton van. This you would need to fit as part of a re-circulating return to tanks. This by-the way will also dislodge any sediment in main tanks, so be prepared for blocked filters. OH the return circuit would also need a non return valve at the tank end else you could wind up with back flow if pump failed, this could suck detritus directly into injector pump.