Fuel Pump Problems

[garwoo]

Hi everyone
My fuel pump has been partially restored, the bottom half. I purchased a repair kit with a new Impeller. It sounds lots better than it did before but although the the car starts immediately, it stops running Quickly within seconds.
Anyone have any idea why? The engine filter is new.

[dirkbalter]

I think you should first check the amount of fuel that is pumped. 1 liter per 15 seconds coming out the return line at the tank.

[doitwright]

And your fuel tank is clean with a clean tank filter?

[garwoo]

Thanks for the info.  I tried to  find the correct return line at the tank and am still not sure. There is a fuel line that enters the tank next to the main fuel line that goes from the tank to the pump. Could this be what you were referring to or is there a better location?
The fuel tank may be a problem, it may not be as pristine as you would like.

[ctaylor738]

You check the flow on the left side of the engine.  Unhook the flexible part of the return line from the hard line, which should be attached to the frame.  I believe the fitting sizes are 17mm and 14 mm.  You can slip a larger piece of hose over the end of the flexible hose and run it into a container.  I use a 1.5 liter soda bottle.

Cheers,

CT

[dirkbalter]

I just did the test as well for different reasons. I find it easiest to lift the car in the rear a bit and take off the rear left wheel for better access. Locking at the tank, you will see two lines attached with hose clamps to the tank. One goes to the pump and is the supply. The other one comes from somewhere in the front of the car and is the return line. You need another short piece of plugged fuel line to stop the flow of gas out of the tank once the return line is removed. (You can just force a suitable bolt in one end of that piece to plug it).
Drop the return line in a suitable container and turn on the ignition for 15 sec and measure the amount of fuel.

Since you mentioned that you rebuild the fuel pump, make sure the two leads to the pump are connected correctly or the pump will run backwards. (You can just switch them to test)
Also, the fuel pump impeller has tapered fins and has to be installed in the correct direction.

Hope that helps   

[garwoo]

Thank-you all for your suggestions. my apologies For not replying sooner, my health went down hill for a while this month. ( not the virus )
Since I live on an island, local help is limited and leaving the Island is not an option. It appears I have further problems.  One of the brushes has a broken wire since I have to solder that back on and I have a new set of brushes, it seems to make sense to replace them both. My problem is, it's not completely clear where the attachment  points are. Does anyone know if there is a schematic of the (short) pump available anywhere?
Thanks Ed

[dirkbalter]

Ed,
I hope you feel better. Not sure if the picture helps. You may want to contact Baron Youngman, a member here and the resident expert on short style fuel pumps.
https://www.sl113.org/forums/index.php?topic=30661.msg222539#msg222539

[BaronYoungman]

The connection will go from the end of the electrical plastic tab through the coiled up line around a carbon rod to the outside( closest to the edge) indented tab on the holder. The front indent is for the brush connection. Bob

[garwoo]

Thankyou Dirk and Bob for the advise, it makes much more sense to me now.
Will keep you posted. Ed

[Pinder]

Just curious what is the purpose of the coiled copper around carbon rod?

[BaronYoungman]

That is a good question. Some of it has to do with being able to stretch the wire to solder without detaching it from either end and be able to manipulate the wire for it cannot touch metal between the plastic tab and the brush holder. Bob

[Pinder]

ok that makes sense. I was thinking about that fact that if it does it would short to ground.

[jim 56]

Hi awhile ago I talked to a guy from Europarts who rebuilds their fuel pumps.He said the coiled copper around the carbon rod is a RF choke to supress static from the radio.Nobody makes them any more so they use a solid state one.He gave me the website where they buy them from but I never purchased any as a fellow member had a couple he sent me.Now I don't know if he was right but it does make sense.Maybe someone smarter than me would know for sure.BTW I ran my pump on a test setup for a few hours just using 24 gauge wire and it ran fine.