urgent question: fuel pump lubrication

[deQuincey]

hi,

i am finishing the overhauling of my fuel pump, and i want to know if it has its own lubrication by means of engine oil, or on the contrary i am supposed to stuff some high grade grease inside the mechanism

i explain my doubts with this photo, this is the engine wall in which the pump is fixed, please note the little hole in the wall (arrowed in red), that i found very dirty with oil,
i wonder if it is intended for receiving oil from the head and thus lubricate the pump

other possibility is that the oil comes from the pusher rod that acts against the fuel mechanism (blue arrow), what do you think ?

if there is no oil comming, my intention is to introduce some grease (the one for the wheel bearings will do), inside the mechanism

opinions ?

regards

 

[Tundra]

It is self-lubricating by the engine oil as you correctly guessed. The protruding rod goes in and out of the engine head. The fuel pump pushes the rod in ( by means of a spring behind the fuel pump) and the engine rockers pushes it back towards the pump creating a vacuum/suction cycle which is how the gas (petrol) gets into the carbs. This mechanical procedure is why when the car has not been started for a while it could take a few engine revolutions before enough gas is in the carbs for the car to start.

 

[deQuincey]

dear andre

i understand, but, from where is the oil entering the pump mechanisms, from the rod itself ?,

if that is the case from where is the oil leaving the pump and back into the engine

as i said I cannot see any hole, not even a tiny one in the head wall

regards

 

[61porsche]

Oil vapor lubricates the rod and the pump cam.( I've seen the gasket leak.) A dab of high temp grease won't hurt.

It's kinda like the valve stems. Not a whole lot of clearance. Just enough.

 

[Tundra]

Slight misunderstanding. The fuel pump itself needs no lubrication. What does need lubrication is the rod (cam) that goes in & out of the Head. It is lubricated by the engine oil. You should be easely able to pull out this rod with your fingers from the head. You will see the hole in the head. ( a lot of double meanings here).See the picture I attached with the rod out. Hope the picture helps. If you have access to the Blue repair manuals, look at section 13, page 13/31-3.

 

[deQuincey]

fantastic help !

thanks everyone, tomorrow i will assemble it

regards

 

[deQuincey]

Slight misunderstanding. The fuel pump itself needs no lubrication. What does need lubrication is the rod (cam) that goes in & out of the Head. It is lubricated by the engine oil. You should be easely able to pull out this rod with your fingers from the head. You will see the hole in the head. ( a lot of double meanings here).See the picture I attached with the rod out. Hope the picture helps. If you have access to the Blue repair manuals, look at section 13, page 13/31-3.

yes it is clear, but also, somehow part of the oil film that lubricates the rod will end over the solid parts inisde the pump , and there it will condensate and leak, and somehow also it will return to the cylinder head

that are my thoughts

regards