So I'm working on an old VW type 3 with D-jet and a three port crapped out fuel pump.
Since the cheapest stock pump is about $300, the search for an aftermarket fuel pump began. Many veedubbers suggest a pump from an 85 ford ranger, but the pump pressure and flow specs are wayyyy above what the stock pump does. Went for the old stand by, the Walbro 255. I accidentally ordered an in-tank pump....hopefully this won't cause any problems and I can slip the VW's fuel line on the shallow pump nipple...
Anyway, veedubbers speak of the original pump having a one way check valve and AM pumps not, so manual priming is required. This seems like a hassle when one could, in theory, just add a check valve to the fuel line. The question is, in front or behind the fuel line? What does GRM have to say?
Someone has to have a pump here... from the looks of things some 914 pumps were very similar... Note, I am not saying this will work...
But there it is...
914 pump is the same. Best price I can find for a crusty used pump is like $110, which I think is silly.
One thing is that I'm not really sure where this check valve in the pump actually is.
If I were to guess where the check valve was I would guess port R in the picture above due to the size of the housing under that nipple.
At this point take the pump apart at the screws.. What have you got to lose?
It would make the most sense to me to have the check valve in the suction line, that way the pump would never start dry.
Full disclosure : I know nothing of VWs or D-Jet. This is mostly a WAG.
HappyAndy wrote:
It would make the most sense to me to have the check valve in the suction line, that way the pump would never start dry.
Full disclosure : I know nothing of VWs or D-Jet. This is mostly a WAG.
This is what I was thinking, since supposedly the whole point of the check valve is so you don't have to prime the pump before starting.
So.....in front of the pump.....?
Convert it to a two line system, 190 or 255 walbro (in tank or external they like to have a flooded inlet). Walbro pumps have a check valve, no priming needed.
Bring the line from the pump through a large filter up to the fuel rail, connect regulator (Aeromotive 1000?) to other end of rail.
Return fuel to tank.
This gives you a recirculating type fuel system which keeps the pump cool and purges any air bubbles from the fuel rail.
Spirited driving is going to cause fuel slosh and you are going to get air bubbles this will cause misfires on a single line system as the air only has one way to escape, through the injectors.
This confuses me. I assumed this was a 2 line system, since it has 2 lines (feed and return).
bentwrench wrote:
Convert it to a two line system, 190 or 255 walbro (in tank or external they like to have a flooded inlet). Walbro pumps have a check valve, no priming needed.
Bring the line from the pump through a large filter up to the fuel rail, connect regulator (Aeromotive 1000?) to other end of rail.
Return fuel to tank.
This gives you a recirculating type fuel system which keeps the pump cool and purges any air bubbles from the fuel rail.
Spirited driving is going to cause fuel slosh and you are going to get air bubbles this will cause misfires on a single line system as the air only has one way to escape, through the injectors.
