Restoring fuel pump

[Azazello]

I am rehauling my sev marchal fuel pump... everything cleaned, gasket changed, filter cleaned... but can't change the membrane, cause It is not bolted and seems too difficult to undo from the shaft.




I was thinking of substituting the shaft with a little m4 bolt, the head at the base working on the lever and a couple of bolts at the right height to keep in position the membrane...
Do you experts think it will work? Any problem I don't see?

 

[mojobaby]

In your last photo it looks like the shaft has a join at the base. Have you tried to unscrew it? with long nose pliers?
What does your diaphragm replacement look like?

 

[Azazello]

It has no screws or anything. .. the diaphragm is a red rubber sheet, circular and with 8 holes on the circumference and 1 in the middle...

 

[mojobaby]

I found this on "Sylvie Renault4". You've probably looked at it already. It seems like a difficult job to do and not always successful.
It will be interesting to see what you do. Change it or leave it as is(if its working correctly).
http://www.la4ldesylvie.fr/index.php?option=com_content&view=article&id=160&Itemid=69

 

[malcolm]

I think the original fixing was turned over like a rivet. Fuel pumps aren't really designed to be serviceable so will be a hassle to fix.. Why not buy a shiny new one? I use electric furl pumps on mine which really helps starting.

 

[Azazello]

The tutorial on "la 4L de Sylvie" is what I started from, never thought by myself of a possible le fault of the fuel pump...
I like reusing and restoring, but of course if I fail I will buy a new shiny one, Malcolm!
My old pump membrane was in good condition, so I left it as it was and just cleaned and changed gaskets (melun sells a gasket set with new diaphragm for 6- and 8-holed fuel pumps).
I have another fuel pump from a dismissed engine, in good shape but with rusty parts, and will try to play with it... swapping the diaphragm shaft with a 4mm bolt! Tomorrow, if I have time, will show in a photo what I plan to do.

 

[Grenuj]

how to disassemble the diaphragm rod?
@Azazello , did you succeed?

 

[orsome]

I think the original fixing was turned over like a rivet. Fuel pumps aren't really designed to be serviceable so will be a hassle to fix.. Why not buy a shiny new one? I use electric furl pumps on mine which really helps starting.

Hi, When using electric fuel pump,do you have a return line organized somehow prior the priming pump or to the tank itself?

 

[malcolm]

The ones I've used have never needed a return line. They tend to work to maintain a certain pressure and don't go above that. Best to select a low pressure one for the R4.

 

[Grenuj]

@malcolm , from which car it fits? How you closed the hole and where you mounted the electric pump?
can you add pictures pls?

 

[malcolm]

I don't have the car any more and didn't take photos. I don't remember which pump I used but it had 8mm pipe connections and it was messy to adapt to fit to the R4.

The pump was mounted to the inside of the chassis in some free space below the right side engine mount. I used a generic / universal after-market one. The difficulty is finding one with 6mm inlet and outlet pipes as most car fuel pumps are 8mm. Motorcycles normally have 6mm fuel pipes so they are probably the best ones to look at.