[SEL] IHC M 3 HP Status

[FRM8198 at aol.com]

Hi List,
The fuel pump which I ordered from one of Harry's vendors was for a  1½" M 
and wouldn't work on the 3 HP.
Now, I am in the process of fabricating a fuel pump.  The pump  body is a 
piece of ½" x 4" water pipe.  The rough inside of the pump  body was smoothed.  
The piston rod is a piece of heavy wall brass tube  which has been plugged on 
both end.   About 3/8" from the bottom end a  grove was machined for a nylon 
piston ring ("O"  ring).  
The bottom part is a reworked  brass gas fitting (½"  npt/3/8" flare).  The 
flare end of the fitting was drilled and tapped  for 1/8" npt.  A 1/8" npt/¼" 
elbow for the intake side screwed into  the modified flare end of this fitting. 
 The top of the 90 degree fitting  forms the seat for the inlet check valve 
ball.  The internal check valve is  a ¼" diameter brass ball.
A 7/16" brass nut was silver soldered to the side of the lower  modified 
brass gas fitting to facilitate connection of the output  check valve .  Then, 
this soldered nut drilled and tapped for ¼"  npt.  A ¼" male/female 90 degree was 
screwed into modified brass nut and a  spring loaded ¼" npt x 3/8" check was 
screwed into this 90 degree  fitting.
The top of the plunger assembly was machined from a ½" npt pipe cap  and fits 
between the engine's fuel pump actuating ears.  A short piece of  ½" npt pipe 
was screwed inside of this cap. The sides of this cap was  drilled and tapped 
for 5/16" diameter pins which mate with the engine's  fuel pump actuator 
ears.  After the matching ears pins were screwed into  the cap, the pins along 
with. the short ½" diameter pipe was  silver soldered.  This assembly was then 
attached to the  upper end of the plunger rod.
A plunger rod return spring was placed on the plunger rod between  the top of 
the cylinder and the modified cap.  Pushing rod  downward, cause the intake 
check valve to close, and  forces fuel out  of the output check valve.  The 
spring action pushed the plunger rod  upward, pulls fuel into the pump body 
through the intake check valve. 
A manual test of the pump assembly was accomplished using  water.  About a ¼ 
ounce of water was expelled (½" diameter x ½"  stroke) with each downward 
action.  
The only operational problem found is that the return spring is  about 3/8" 
to ½" short.
Next, a metal bracket has to be made in order to install the  fuel pump 
assembly on the engine.  

Francis  Maciel
Santa Maria, Ca