Anyone Know This Logo?

[cpwolf]

So that answer is maybe. These mechanical pumps are more or less gravity fed, and can't do much "sucking". With the line unhooked at the pump and a 1/2 tank or so of fuel, the line should be free flowing, and you should be able to easily get a siphon started. (Be aware, I had one I couldn't get stopped ) Start there, make sure the tank-to-pump line is clear, or whatever your supply line is, and all rubber in the line is in good condition.

After that, we're at the pump. You can test the pump to see if it's in good condition. If it is, mount the pump and hook up the supply side to see if you can get fuel through it.

If you can't, then I’d start looking at the cam/pushrod. I'm not familiar with these engines, I don't know if the pump runs on the cam directly or uses a pushrod like a SBC/BBC or MoPar B/RB (those are what I'm most familiar with). If it can push fuel through, then you're down to pump-to-carb.

What problem(s) were you originally having?

It runs on the eccentric mounted on the cam directly.

Took long time to start after sitting.

Then when it had been run, it ran great started easy even after a couple hours. Week later took time.

Then I changed oil, smelled fuel (so diaphragm most likely leaking).

Then after sitting just won’t get fuel to clear fuel filter, I know it’s not pumping. To filter.

 

[BlueC]

Then I changed oil, smelled fuel (so diaphragm most likely leaking).

Then after sitting just won’t get fuel to clear fuel filter, I know it’s not pumping. To filter.

Fuel dilution can also come from running rich, running cold and/or short run times. If you have just been letting it run for 5-10 minutes at a time, well that's bad. You say it sat for a while, are you dealing with non ethanol fuel or something like e10? Remember these pumps are only capable of 5-6 psi so they might not be able to clear junk out or push through a mildly clogged filter, which as cheap as they are you should replace. When you know the supply line is clear and that the pump diaphragm is good (I'd even check a new pump), leave the pressure side unhooked and see if it will move fuel through the pump.

 

[cpwolf]

Fuel dilution can also come from running rich, running cold and/or short run times. If you have just been letting it run for 5-10 minutes at a time, well that's bad. You say it sat for a while, are you dealing with non ethanol fuel or something like e10? Remember these pumps are only capable of 5-6 psi so they might not be able to clear junk out or push through a mildly clogged filter, which as cheap as they are you should replace. When you know the supply line is clear and that the pump diaphragm is good (I'd even check a new pump), leave the pressure side unhooked and see if it will move fuel through the pump.

First, huge thanks for the help.

So leaving it sit will get fuel in the oil, or give it an oil smell? I had thought that was primarily a fuel pump issue, but I hear ya.

It sat for a while, I bought it, and it ran. I fire it up every couple weeks and drive around. Drive to wherever and give it a good run. In Texas, this July, just turned into a blast furnace and I was super busy, so it sat for about 2 months. Then wouldn’t start. I pulled the fuel line from the carb, not getting fuel. I pulled all that and it’s clear. So I went to the pump, knowing the smell in oil, just felt it probably died.

I need to work back, make sure all the lines are clear.

I tried to isolate it all, but just a hose to the new pump from a gas can, and then a hose to a bottle. Nothing, pumped, so I know there’s an issue with
1. 3 feet of brand new fuel hose that I can blow through
2. The new pump
3. The new hard line I just installed and can blow through
4. The 2 feet of hose that after that.

I pulled the new pump, and it looked like it was riding the eccentric in the cam from subtle marks just like the old pump.
Either I got a bad “new” pump, or not having that hose clamped on the inbound pump nipple it sucked air and wouldn’t pull fuel. The can was straight below on ground, so no gravity help. I think eliminate that variable. Filter I took out of equation to see, but agree new one I’ll do, just now I know it’s not the stop.

 

[Squatch]

In your search for a fuel pump, don't rule out the 290, 343, and 390 AMC V-8s, as well. They are all from the same family. One thing you'll want to be careful of is that some of the fuel pumps for the older engines have provisions for vacuum wipers. These pumps have a different appearance, and are bulkier, as I recall, so you wouldn't likely be considering one if you saw it.

I'm not saying that I'm 100% sure on the interchangeability, but I am fairly confident that they are.

 

[cpwolf]

In your search for a fuel pump, don't rule out the 290, 343, and 390 AMC V-8s, as well. They are all from the same family. One thing you'll want to be careful of is that some of the fuel pumps for the older engines have provisions for vacuum wipers. These pumps have a different appearance, and are bulkier, as I recall, so you wouldn't likely be considering one if you saw it.

I'm not saying that I'm 100% sure on the interchangeability, but I am fairly confident that they are.

Appreciate the help. I’ll keep looking. I’m looking at the 304, 360 and 401, those all look interchangeable. The upside down one, which fits, was in the AMC Car V8’s, and early CJ’s it seems, so it should work. I’ve got to get off these dang work trips and do some more testing on the upside down one. It should work, I have to have done something wrong in my tests.

 

[cpwolf]

Y’all are awesome for helping, if I can get this dang thing going, and off my brain, I can get back to my TJ and get the Savvy TC Skid, Engine Skid, Savvy body lift and MML, and the Exogate tire holder all on my 05. Ha

 

[Squatch]

Is this similar to what you're after? I pulled this from NAPA for a '72 Matador.

 

[cpwolf]

Is this similar to what you're after? I pulled this from NAPA for a '72 Matador.

View attachment 478615

That one installs with the stacks facing down in the engine. I can tell by bolt pattern, it’s the replacment I got. If I can get figured out, it will work. Thanks.

The one that came off, has those stacks shorter, but bolts on facing stacks uo. I can tell by the bolt pattern shape.

 

[Squatch]

That one installs with the stacks facing down in the engine. I can tell by bolt pattern, it’s the replacment I got. If I can get figured out, it will work. Thanks.

The one that came off, has those stacks shorter, but bolts on facing stacks uo. I can tell by the bolt pattern shape.

Okay. I'm still looking.

 

[Squatch]

Thought this might interest you...

 

[cpwolf]

Thought this might interest you...

View attachment 478617

Agree, and I’m working that. Much appreciated. No need to look, the height is a very small Diff, not sure we can tell by a pic. I’ll go part store hopping when I get back if I can’t get the upside down one working

 

[BlueC]

Look at that, squatch found his way in without me calling him. I bet his AMC senses started tingling.

So leaving it sit will get fuel in the oil

Possibly, which could come from a leaky carb. Typically, fuel dilution comes from running fat (rich a/f mix, running cold (not enough heat to boil off fuel & water), or from running for short periods of time which combines running fat and running cold into one event. That will even happen with modern fuel injected vehicles. Vehicles really need to be brought up to temp now and then. I typically tell people to do a 30-minute drive every week or two.

On that subject, I hope you're running a good ZDDP oil like ZR1 just to be easier on those flat tappets/cam.

It sat for a while, I bought it, and it ran. I fire it up every couple weeks and drive around. Drive to wherever and give it a good run. In Texas, this July, just turned into a blast furnace and I was super busy, so it sat for about 2 months. Then wouldn’t start.

So it did run fine 2 months before sitting? Did it sit with ethanol fuel in the tank? Will it run with you feeding it fuel?

I pulled the new pump, and it looked like it was riding the eccentric in the cam from subtle marks just like the old pump.
Either I got a bad “new” pump, or not having that hose clamped on the inbound pump nipple it sucked air and wouldn’t pull fuel. The can was straight below on ground, so no gravity help. I think eliminate that variable. Filter I took out of equation to see, but agree new one I’ll do, just now I know it’s not the stop.

If the new pump is off, then I’d vacuum test it, like in that video I linked. If it's on the engine, I'd just try again with the can elevated. Typically, I just sit them inside the engine bay near the pump. Keep a fire extinguisher nearby, I lost a good hat doing this one time in a parking lot.