Is there a difference between the fuel pump lobes on 2F vs. F.5 cam? (2 Viewers)

[insightbrewery]

Hey guys, I have a weird issue here: the fuel pump won't fit/sit flush on the block on this 1974 F.5 that I'm working on. Here's the story:

Bought a fuel pump rebuild kit from Cruiser Cult, but opted not to rebuild the fuel pump because (a) the arm had a divot worn in it and (b) was expecting it to have valves held by a retainer plate, but found staked valves instead; given the state of the rest of the pump with rust and sludge intrusion, I figured we might as well buy a new pump. I checked the parts diagrams/OE part number for this engine and the latest supersession is 23100-61011, which I bought from City Racer.

Several months ago, I sent the original (cast with "teq") camshaft to Delta Camshaft for repair: same reason the old fuel pump arm was worn, this engine was so badly sludged that oil was basically not getting anywhere. They repaired two lobes, the fuel pump lobe, and put a mild grind on it.

The cam's been installed for some weeks now, and I just now got to putting the fuel pump in and find that it doesn't sit flush with the block when the arm is sitting on the highest point. I didn't bolt it up because I didn't want to bend the arm or something. I verified that the pump is the correct one. My question is this: is there a difference betwen the fuel pump lobes on an F.5 camshaft (which I assume is the same as earlier Fs) and a 2F camshaft? The Delta Camshaft receipt lists "2F" on it, so I'm wondering if the lobe is too fat/meant for use with a spacer'd fuel pump and thus preventing this one from seating.

Unfortunately I threw out the rotten guts of the original fuel pump, but I will rebuild it with the kit to test fit, since it was bolted to the block without any issues before the cam was repaired.

TIA!

EDIT: The pump arm only moves 4-5mm at the tip right?

 

[71-CRUISER]

Depending on the pump / engine block that you are using you may need a spacer between the pump and block.
it’s about 3/8” thick

the cams are the same from what I know.

 

[insightbrewery]

I contacted City Racer and they verified that cams are the same from F through 2F. I'll try to fit again today and post up a pic.

 

[3_puppies]

2 lines on the fuel pimp = no spacer, mounts directly to block with a gasket
3 lines on the pump = requires a spacer between the pump and block, if installed with no spacer, the pump arm is destroyed and needs replaced

 

[insightbrewery]

2 lines on the fuel pimp = no spacer, mounts directly to block with a gasket
3 lines on the pump = requires a spacer between the pump and block, if installed with no spacer, the pump arm is destroyed and needs replaced

Yeah both my old and new pumps have two lines. Problem is it seems to sit off the block - no spacer - with the cam lobe engaging the arm fully. I can install it when the cam lobe is pointing away from the arm, but I don't want to risk bending the arm when it comes back around.

 

[B y r o n]

You should be able to push the pump body against the block. When looking at the pump, manually compress the arm to get an idea of how far it will/can move. That may ease your mind some about the body being pushed away from the block. Easiest install is with cam away so the pump is simply lined up and bolted down.

 

[insightbrewery]

WELL. I feel like an idiot: I was only pushing the arm by hand as far as the slop that the spring takes up to ensure positive contact. I pushed harder and heard a loud squelch as the diaphragm moved. Haha! Thanks to all who replied, apologies for wasting time.

 

[B y r o n]

Glad you were able to resolve things!

 

[secretsquirrel]

hey someone in the future will learn from this post. I already have. Thanks for asking the question