Fuel Pump Help

carl, Dr.Jeff..thanks for your input. The mechanical pump works fine at the moment once fuel lines and carburetors are charged. I am hoping to avoid the requirement of prolonged cranking after extended lay-over. The upside is that the oil pressure is up by the time the engine lights-off. I was envisioning a couple of T pieces off the fuel line to feed the electric pump before the mechanical pump. The idea is to prime the system.
Peter how did you go with the electric pump before the mechanical pump ? My ideas as well on a fuel system thats been cleaned and devoid of fuel other than in a cleaned tank for 3 years. Interesting to know how you went.

Michael
 
I only had an issue with the mechanical pump when I put on the DCNFs. They vent to the atmosphere so it takes some cranking to refill the fuel bowls. It was never an issue with the stock carb. But, as mentioned above, it does allow time for the oil to get moving so I have no problem giving it some extra cranks.
 
Starting from a three year lay-up with cleaned tank, strainers, empty metal filters and lines to new mechanical fuel pump and empty carburetor bowl. How much cranking before it starts. Particularly with only static timing of new distributor. Was thinking aerosol ether down the carburettor throats with lid on filter in case it 'burps' A temporary FACET electric to prime system then remove it once fuel system is fully primed and engine running.

Michael
Try filling the carb bowl through its vent first. Then start the engine and let it idle on that fuel. That will help to get the mechanical pump going. Sometimes it can take quite a while so you might to refill the bowl more than once.

I do not believe you can run both a mechanical and electric pump at the same time. Often the mechanical pump is just left in place when a electric one is added, but the fuel lines no longer go to the old pump.
 
Thanks Jeff, Filling carb bowl came to mind, was not sure how. Through its vent with a squeeze bottle or plastic oil bottle/syringe. Hopefully the engine will start. I can see the first start is going to be fun and games.
 
Thanks Jeff, Filling carb bowl came to mind, was not sure how. Through its vent with a squeeze bottle or plastic oil bottle/syringe. Hopefully the engine will start. I can see the first start is going to be fun and games.
Just dribble a little raw fuel from a cup , or squirt of a syringe straight down the carby throat, that will let the engine fire up (provided you have the ignition timed correctly) and the few seconds that it runs should be enough to get fuel to the pump, maybe a second dribble / shot from a syringe and after that it should be good to go.

SteveC
 
Either of the above will work. I am lazy, no surprise there, and just dribble some fuel into the throat of the carb. This gets a the engine running briefly, gets the oil pressure up and creates enough suction going in the mechanical fuel pump to get fuel to the bowl. This may take two tries.
 
Just dribble a little raw fuel from a cup , or squirt of a syringe straight down the carby throat, that will let the engine fire up (provided you have the ignition timed correctly) and the few seconds that it runs should be enough to get fuel to the pump, maybe a second dribble / shot from a syringe and after that it should be good to go.

SteveC
Thanks Steve, yes a squirt of fuel down the carby throat should work. Yes Cover up throat with air cleaner cover in case timing is slightly out. Fun and games of a re-start after long lay-up.

Mike Salvador
 
Peter how did you go with the electric pump before the mechanical pump ? My ideas as well on a fuel system thats been cleaned and devoid of fuel other than in a cleaned tank for 3 years. Interesting to know how you went.

Michael
Michael, greetings. My post was as far as that went. I still think that I would like to be able to add a fuel pump for priming purposes. If anyone can add to this, would the mechanical pump be able to "pull" fuel through an electric pump if it were placed in-line
 
Peter hello and thanks for reply. I am looking at all possibilities of getting fuel to the engine for an initial start with empty fuel lines and new mechanical fuel pump. Many idea and ways without being messy with neat fuel in putting it directly into the carburetor bowl and throat with a syringe or plastic oil squueze bottle. Even thw aereosol ether trick. Wary of covering up carb throat with air cleaner cover. Not sure how good my new Bosch ditributor static timing would be for a back-fire. I would imagine an electric fuel pump would pull fuel up from fuel tank to lines if suitably connected, with care with electrical connections away from fuel/ignition danger. With my previous Japanese cars and English cars electric pumps did a splendid job, until their points burned and they became intermittent. Many a night hitting a Smiths electric fuel pump with a screw driver handle to limp home in an original 1968 Mini Cooper S with a thirsty Weber DCOE.
 
@milan1951, I faced this problem too but as a boater the solution was immediately obvious. Outboard motors have a priming bulb in the fuel line. If you search online, this was a common add-on for Lancias back in the day. Take care though, they harden, crack and leak so should be only used temporarily after a lay-up or maintenance. Do not leave it permanently installed, they don't stand up to heat.
 
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Neil great idea. I too have had to squeeze the black plastic priming bulb between the red fuel tank on the boat floor and the two stroke outboard motor. Similar to plastic squeeze bottle to squirt some in carb bowl or down carby throat. Careful to wiping up any spills.
Have not used too many boat priming bulbs that were not in good condition. Mostly hire boats or loans.

Mike Salvador
1982 1500 X 1/9 with carburetor
 
A positive cure for the X1/9 mechanical fuel pump is the more expensive fuel pump MWB sells. Puts out more pressure than needed, so you install a pressure reducer after the pump.
HINT: Don't connect the power lead the Ignition coil, but use a key on/off circuit
HINT: NO NOT leave the stock mechanical in place, Get a block off plate from MWB. The stock pump diaphragm will split after a time, and pump lots of oil out of the engine, all over. Make sure the oil return for the pump is covered with the block off palte.
 
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