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I'm replacing my old fuel pump on a F-134 engine (53 A1) converted to 12V.

Single action w/ hand primer...is the pump arm suppose to be above or below cam lobe,

read info saying both. Thanks

CHARLEY wrote:...is the pump arm suppose to be above or below cam lobe, read info saying both. Thanks

Hi Charley,

Above. On top.
And if you turn the engine by hand to rotate the cam to it's lowest position (on top) you'll find that installing the pump will be easier.
There'll still be a little arm spring pressure to overcome while mating the bolts through the spacer, but not nearly as much as if the high spot of the lobe was on top.

Could be mistaken, but pretty sure you'd discover that it's impossible to mount the pump arm on the bottom of the cam lobe without bending or breaking something.

Good luck!

How did you end up with a "SINGLE ACTION PUMP WITH HAND PRIMER" . The correct pump for an F134 is a dual action (Fuel & Vacuum) with and/or without hand prime lever.



Your question on pump lever location vs cam lobe raised my curiosity. I did a quick check of fuel pump install instructions in the M38A1's TM 9-8014 and TM 9-8015-1 and no explanation on pump lever location relative to cam. Then a look at the M38's TM 9-8012 and TM 9-1804A and both very clearly stated lever above cam lobe. Now I was very curious and I looked in the two Civvy Willys manuals, SM 1002 for the earlier CJ's and SM 1046 for the later CJ's and neither makes any mention of pump lever vs cam lobe positioning.