Help- '34 won't start- has fire and air...

[Tom in TN]

Ok, ya’ll…I need more brain power than I can muster right now. I just changed jobs last week- more authority, more responsibility and yes, more pay but the massive concentration thing I have going on is sapping my collateral skills… here’s the deal:

About 6 weeks ago, I went out to crank my ’34 for the first time in a few weeks. (specs: 1936 flathead; .060 over; ¾ cam; aluminum flywheel; Dual-point Mallory crab dist; 2 Holley 94’s on a Fenton intake; repo Eddie Meyer finned heads; Skip’s water pumps; fuel pump was the type with NO glass bowl; ~8 yr old Drake steel gas tank)

Poured some fuel down the carbs and it would start and then run out pretty fast. I did that 3 or 4 times and realized that it usually has pulled fuel up into everything by then. So, I went one better and used the carbs vent tubes to fill the float bowls with gas (Unleaded- NO Ethanol, REAL gas). It cranked just fine and ran ok…and then the bowls ran dry.

I have a see-thru, in-line fuel filter and there was no evidence of ANY fuel being pulled into it by the fuel pump. (I had already pulled that filter off and blew thru the fuel line and could tell that air could move thru the line.)

SOoooo, fuel pump has quit on me, right?

5 weeks later, sparing you the long story, I got a new fuel pump –the type WITH the filter bowl and installed it.

Finally got it all buttoned down and today tried to fire it off. Filled the carb float bowls and dribbled some gas down the carb throats and it lit right off and ran just like it always does…until…the float bowls ran dry.

Even with the new fuel pump, I decided to leave my in-line filter in place and after running the motor for as long as it takes to run the carbs dry, there was NOTHING in either filter.

What the heck could be going on?

Any and all advice, hints, admonishments or just plain sarcasm appreciated…

HELP, Fordbarn !!!

[elwood]

needles stuck, both at the same time you ask ? stranger things have happen ..

[Floyd]

My guess is the rubber hose from firewall to fuel pump has collapsed just like all of the typical repro ones do. The only hose you can trust is the one made by Bob Shewman (sp?). I am not a fan of "new " fuel pumps.
My opinion

[Tom in TN]

elwood- I am using a new type needle, it has a flat disk,,,supposed to be unable to stick.

Floyd, I'm not using that rubber hose. but thank ya'll...

[drolston]

Disconnect fuel line from carb; crank engine with ignition off and fuel line in a container. If fuel does not spurt vigorously, you have a bad pump or blocked line someplace. Or an air leaking fuel connection. Is that see-through fuel filter before or after the pump? If fuel does spurt, the unstickable flat disks are sticking; change both float valves to Grosse ball type.

[edhd58]

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Blown air back thru the line to the tank, just to make sure of no blockage?? Maybe cap is not venting causing vacuum??

[ford38v8]

The following issues can cause the problem you've described:

Fuel pump problems include: Dried out gaskets leaking air / sticky valves(s) / blown diaphragm.
Fuel line problems include: Pin holes leaking air / debris clogged line / fittings not sealing leaking air.
Flex line problems include: Collapsed from fuel softened rubber / pinhole leaking air / Fittings not sealing leaking air.
Carburetor problems include: Sticky needle valve / Float inoperative.
Fuel filter problems include: Debris clogged / Spring clamps leaking air.

Notice that most problems involve leaking air?

[37 Cab]

Might check the lift on the pushrod too.

[Bill OH]

Remove the nuts that hold the fuel pump stand to the intake and turn engine over until stand rises to its max height off the intake - .200 gap? If yes, connect vacuum gauge to inlet of pump and push pump up and down to see if it draws vacuum. I have had to prime a pump and I have also experienced stuck valves in the pump - hit the pump with hammer handle or screw driver handle to unstick the valve. I have experienced this on more than one occasion. If all of this fails, try priming the pump from the intake side with gas. Another thing you could do is install an electric pump pump at the tank for priming and emergency use. And it may be that the inlet valves in the carbs are stuck, but on two carbs? Maybe. I have seen a carb inlet valve stick. When you put in the new gas tank, did you run a new gasline? If using the old line, you may have pin holes in the old line admitting air.

[Tom in TN]

37 Cab:"
Might check the lift on the pushrod too."

This the issue that scares me the most...this other stuff I can eventually find and correct, but THIS???...how the heck can you fix it?

[flatjack9]

Replace the cam. Only way. Or go totally electric.

[Tom in TN]

Latest update... I took the fuel line loose and hook a vacuum pump to it and fuel came up out of the tank just fine. So, no obstructions there.

Next up, remove the pump stand with new pump still attached, and use a dial indicator on a magnetic base to measure how much lift the pushrod is delivering.

Bill OH, you said ~.200"... is that the factory lift spec for the pump rod?
If not, does anyone know the book spec that I need to look for?

Thanks fellas...

[grumppyoldman]

I have a pump with glass bowl attached, the arm is not in the same position as the non glass bowl I'm running. I wanted to do the same thing you did but pump with bowl would not work on my engine. The push rod would not stroke that pump enough to make it work. Information I found said it was for 46 thru 48, so I give up. Al

[flatjack9]

Factory spec on lift is.20.

[Bill OH]

I used a glass bowl fuel pump on a 33 Ford 1.5 ton truck with 221 stock and original engine.

And I use a glass bowl pump on a 38 ford 221 with Isky cam and used glass bowl pumps on two other stock 38 fords 221. Worked well.

As to the .200 lift, a 6/32 drill bit will just nicely give a good approximation of the .200.

I always leave the pump stand gasket out and use a thin line of RTV cement. Gives more stroke.

I would check that fuel pump for vacuum on the inlet and pressure on the outlet.

Connect the fuel pump to the line from the tank and use a blow gun to drive gas to the pump. Then look at the line from the tank for wet spots.

[Bill OH]

Another thought: I always use a neoprene glass bowl gasket in place of cork. I learned this years ago using a fuel bowl gasket from a Massey-Harris 44 farm tractor. I will probably draw flak on this, but I have had good success with neoprene. Do not use a rubber gasket - it will swell!!! We'll see who jumps on that statement. You might try NAPA for a neoprene gasket. Cork gasket leaking?

[Paul Bennett]

First pump bad.
Second pump wrong length push rod.
Ya just can't win these days.
Lots of recent threads about measuring pump rod length, that's good.

[Mart]

Not sure if the above is a guess at what may be wrong, or a statement of what has been found to be wrong.

The pump push rod is stroking. Fit the pump and remove the pipe from pump to carb, redirecting it into a can.

Crank the motor and watch to see if there is a good stream of fuel squirting from the pump.

When I started the 21stud in my 33 it ran ok when the pump was hand primed but stopped when the pump was asked to pump for itself. I had to lengthen the push rod to get the pump stroking in it's sweet spot.

Mart.

[Tom in TN]

Thank for all the thoughts, fellers- I will be working on this deal today and will report back with what I found and any successes or failures...

Happy labor day !!

[tubman]

Originally Posted by Bill OH

Another thought: I always use a neoprene glass bowl gasket in place of cork. I learned this years ago using a fuel bowl gasket from a Massey-Harris 44 farm tractor. I will probably draw flak on this, but I have had good success with neoprene. Do not use a rubber gasket - it will swell!!! We'll see who jumps on that statement. You might try NAPA for a neoprene gasket. Cork gasket leaking?

Funny, I have always had better success with cork gaskets. One thing I do is use wet or dry paper on my surface plate (2" slab of perfectly flat granite) to make sure the gasket surface of the glass bowl is dead flat.