Outboard external fuel tank vertical position

[gordmac]

Personally, a float chamberful. Long enough to get the salt out of the system and run the carb dry.

It certainly sounds like a height issue. One way round it that might be a bit less faff than making a new home for the tank would be to go to a car breakers and get a electric fuel pump wired into the engine output. Always assuming you have a 12v output, of course!

You need to be careful doing that, for several decades cars have been injection and have fuel pumps with high flow capable of providing 3 or 4 bar pressure. No use for a carb.

 

[Stemar]

You need to be careful doing that, for several decades cars have been injection and have fuel pumps with high flow capable of providing 3 or 4 bar pressure. No use for a carb.

Good point. I got one for a project years ago and, while it would pump well, a finger over the end stopped it.

 

[chris-s]

A little update.

Quick recap, new engine, tank, hose and fuel with the tank below deck kept needing to be re-primed after 20minutes. Second new tank and hose on deck ran fine for 40+ minutes.

Yesterday I spent five hours motoring up and down the Carrick Roads trying different combinations of the two tanks, their hoses and tank positions. I won't bore you with all the details, suffice to say that the second temporary tank hose was transparent and gave the game away by allowing me to see some air appearing in the line when connected to the original tank positioned below the deck. After checking all the joins and swapping out some jubilee clips which had jammed not-quite-tight, the last run was 1.5 hours with one bubble (probably from me messing around) and no issue.

I'm guessing that its harder for the pump to pull from the tank in the lower position revealing any less-than-perfect joins. So, yes the engine will pull from that position, just got to make sure the everything is tickety-boo with the pipe work. I'm going to junk the jubilees and fit some better hose clamps, replace the o-ring which is fitted between the hose barb and pickup pipe head and might even use some blue hylomar on the joins.

Thanks for all the previous help

Chris

 

[Refueler]

A little update.

Quick recap, new engine, tank, hose and fuel with the tank below deck kept needing to be re-primed after 20minutes. Second new tank and hose on deck ran fine for 40+ minutes.

Yesterday I spent five hours motoring up and down the Carrick Roads trying different combinations of the two tanks, their hoses and tank positions. I won't bore you with all the details, suffice to say that the second temporary tank hose was transparent and gave the game away by allowing me to see some air appearing in the line when connected to the original tank positioned below the deck. After checking all the joins and swapping out some jubilee clips which had jammed not-quite-tight, the last run was 1.5 hours with one bubble (probably from me messing around) and no issue.

I'm guessing that its harder for the pump to pull from the tank in the lower position revealing any less-than-perfect joins. So, yes the engine will pull from that position, just got to make sure the everything is tickety-boo with the pipe work. I'm going to junk the jubilees and fit some better hose clamps, replace the o-ring which is fitted between the hose barb and pickup pipe head and might even use some blue hylomar on the joins.

Thanks for all the previous help

Chris

Glad you have arrived at solution.

 

[rogerthebodger]

A little update.

Quick recap, new engine, tank, hose and fuel with the tank below deck kept needing to be re-primed after 20minutes. Second new tank and hose on deck ran fine for 40+ minutes.

Yesterday I spent five hours motoring up and down the Carrick Roads trying different combinations of the two tanks, their hoses and tank positions. I won't bore you with all the details, suffice to say that the second temporary tank hose was transparent and gave the game away by allowing me to see some air appearing in the line when connected to the original tank positioned below the deck. After checking all the joins and swapping out some jubilee clips which had jammed not-quite-tight, the last run was 1.5 hours with one bubble (probably from me messing around) and no issue.

I'm guessing that its harder for the pump to pull from the tank in the lower position revealing any less-than-perfect joins. So, yes the engine will pull from that position, just got to make sure the everything is tickety-boo with the pipe work. I'm going to junk the jubilees and fit some better hose clamps, replace the o-ring which is fitted between the hose barb and pickup pipe head and might even use some blue hylomar on the joins.

Thanks for all the previous help

Chris

Leaks on the suction side of a fuel system can be bu**er to find. I had that on one of my diesel tanks with a faulty weld on the suction side of the dip tube.