Is it a MOPAR?What year?Is it a fuel pump?

[Fernando Mendes]

http://imageshack.com/scaled/800x600/571/a07s.jpg

 

Is it a MOPAR engine?

What year is it?Before 1929?carburetor upside down.

Is it a fuel pump?

[greg g]

the canister on the firewall is likely a vacuum fuel pump.  these were mostly phased out by 1930. This is Isentified as a 1929 Dodge Brothers truck engine.  Looks real close

 

 

[Fernando Mendes]

Ok many thanks for you.

[Fernando Mendes]

Greg G,I have another question:How does the gasoline arrives at the intake manifolds and cylinders chamber?Who pumps it?

[Dave72dt]

It's called an updraft carburetor. Atomized fuel and air are drawn into the intake and combustion chamber by the low pressure created by the piston on it's downward stroke with the intake valve open, same as on a downdraft or sidedraft carb. Pump works off the same manifold vacuum.

[greg g]

Up draft carbs are pretty common still.  Lots of tractors, industrial applications, stationary equipment.  Typically used where throttle openings are constant and or controlled by a governor. In cars where throttle openings are changing frequently, the went out of fashion in the early to mid 30's as cars gained power, and roads improved and speeds went up.

 

Manifold vacuum works whether it sucks up or down to pull gas through the carb jets, typically updrafts forgo things like accelerator pumps, power circuits and adjust-ability, basically idle speed and idle mixture.  

 

Generally with  the set up like the one posted, the vacuum pump, which comprises a bladder (think of it like a hot water bottle with a couple of check valves) in a vacuum chamber pulls fuel from the tank, then feeds it to the carb by gravity.  The vacuum collapses the bladder as it empties, then the vacuum is released, the bladder expands and sucks gas from the tank. Some use  the vacuum building within the chamber as it starts to build again to slightly pressurize the line from the pump to the carb. by squeezing the bladder as it empties.

[Fernando Mendes]

Thanks,many thanks.But I have another question yet.Now this question is about the new(actual) fuel pump.When the arm pump is moved by the camshaft?From each degrees or turn of the camshaft it moved?

[Dave72dt]

yes, it follows a lobe on the camshaft, same as a valve lifter

[Fernando Mendes]

yes, it follows a lobe on the camshaft, same as a valve lifter

[desoto1939]

Fernando: I guess you are confussed when you put the face icon on the reply about the cam lobe.  On the crankshaft there are lobes  or high points that make the valves open and close. There is also a lobe or high point on the cranshaft for the fuelpump. The lever that comes out of the fuelpump that goes intot he block is pushed down when the egine is running and this cause the lever to move and then the diaphram inthe fuelpump creates a vacuum to draw fuel from the gas tank and then send fule up to the carb.  So as the engine spins faster then the FP  will pull more fuel to the carb.

 

Hope this answers your question

 

Rich Hartung

desoto1949@aol.com

[Fernando Mendes]

No.I would like to know if the lobe fuel pump in the camshaft touches the lever at each 120 degrees of camshaft turn for example.My doubt is that.

[desoto1939]

No.I would like to know if the lobe fuel pump in the camshaft touches the lever at each 120 degrees of camshaft turn for example.My doubt is that.

 

Fenando:  I do not know the answer to that question either.

 

rich hartung

[Dave72dt]

You should be able to tell by looking at the cam lobe for the pump.  Bright and shiny all the way around would indicate it does.   An incomplete ear pattern would indicate it does not.  I'll would think it does simply to take up any slack in the mechanisms of the pump and to remove possible arm bounce from it being struck by the cam lobe instead of sliding up and down it

[TodFitch]

Last fuel pump I looked at in detail had a two piece/double spring arrangement. Looked like it was setup for the arm to always ride the cam but the diaphragm only was pulled down as needed to suck more gas into the pump. Net result is that during times of low fuel usage the diaphragm does not move as much as during times of high fuel usage.