Fuel pump failed

[Malcolm Towrie]

Hi, I'm working on a restored carrier and I found that the fuel pump, despite looking like new, had quit. It wouldn't pull enough vacuum to get the fuel up from the tank.

I pulled it off and confirmed there was very little vacuum being generated at the inlet port.

I opened it up and found the diaphragm has crazy-paving cracking all over the wet side. I'm thinking the dreaded ethanol problem, though we usually use a Shell gasoline that doesn't have any ethanol. Maybe it was from before we got it.

Does anyone have recommendations for a good, ethanol-resistant replacement? I'm not a fan of electric pumps but is the conversion popular?

(By the way, I checked I was getting 0.2" stroke on the pump rod, and the pump lever height was correct to get the the full 0.2" stroke on the pump lever.)

Malcolm

[RichardT10829]

I went with a facet pump initially but have since gone back to the mechanical pump.

[Michael R.]

Preference for original 221 flathead Canadian carrier engine?

Carter USA made, in-line 6v, $66.35 from Mac's Auto, Lockport. Comes with filter.

[rob love]

$13 will get you a replacement diaphragm from Mac's, or for around $90 you can get a brand new mechanical pump from your local NAPA (part number 571)which will have both ethanol resistant diaphragms and check valves.

Personally I am running the mechanical pump on my own carrier as well as the ones form work. I run a filter just before the fuel pump as any sediment getting to the pump will dislodge the check valves and cause the pump to merely idle.

[Malcolm Towrie]

Originally Posted by RichardT10829

I went with a facet pump initially but have since gone back to the mechanical pump.

The Facet cube pump is the one electric pump I like, since it is a similar design to a mechanical pump with the spring generating the pressure and the self-regulating piston stroke. But they look like they are very sensitive to dirt with the tight clearances. I believe the lack of an inlet side filter caused lots of problems in the Iltis.

Anyway, why did you switch back?

Malcolm

PS, I didn't know Facet made a 6V pump. It doesn't show on their web site.

[Malcolm Towrie]

Originally Posted by Michael R.

Preference for original 221 flathead Canadian carrier engine?

Carter USA made, in-line 6v, $66.35 from Mac's Auto, Lockport. Comes with filter.

I have a 6V Carter 4259 rotary vane pump but when I tested its dead-head outlet pressure it was 8 psi. And a high flow pump like that will spend a lot of time close to dead-headed on a carrier. I have had problems on other vehicles with supply pressures higher than the carb was designed for blowing the float needle off the seat and causing rich running and flooding so I was leery about using it. I guess I could use it with a return line to keep flow high so the supply pressure to the carb is lower.

Sounds like you haven't had any problem, though?

Malcolm

[Malcolm Towrie]

Originally Posted by rob love

$13 will get you a replacement diaphragm from Mac's, or for around $90 you can get a brand new mechanical pump from your local NAPA (part number 571)which will have both ethanol resistant diaphragms and check valves.

Personally I am running the mechanical pump on my own carrier as well as the ones form work. I run a filter just before the fuel pump as any sediment getting to the pump will dislodge the check valves and cause the pump to merely idle.

Thanks, Rob. I'll get the NAPA 571 one. Somebody already installed a filter upstream of the pump.

Malcolm

[rob love]

Personally I rethread one of the old inline 70s Ford filters that use to screw right into the carb. You will need to rethread the pump over to 1/8 NPT.

That way I can use double flared steel lines instead of the original compression fittings. To adapt those I use Weatherhead 1074 fittings along with a fiber washer. It will go into the carb, the fuel pump, and the changeover valve. I got tired of dealing with stripped carb inlets...this way the fitting takes the force.

[Malcolm Towrie]

No problem. I can handle the fittings. I like the challenge.

[RichardT10829]

Despite inline filters either side of the pump it would pick up the slightest bit of muck and it would block.

I also found with the pump being mounted in the engine bay, on long hot runs the pump would vapour lock, or would appear to vapour lock.

I ran mine mounted to the lower plate on the rear of the hull and had an adjustable "King" filter and reg... The stromberg 97 carb I used only liked a maximum delivery pressure of 2.5psi and the facet was capable of more than this.

I ran an inline fuel pressure gauge too.

Facet don't do a 6v pump....I am running 12v system on the engine, I have a regulator box and some magic trickery hidden away so all my 6v gauges still work as they should.
A pal re flashed my generator to charge for 12V (it was a three brush genny with one brush removed)

[Phil Waterman]

Hi Guys

One thing I've noted is that fuel pumps mechanical or electrical don't seem to like standing empty and dry once they have had ethanol gas through them. They seem to loose the ability to self prime. Some times once you get fuel back into them they will start working again.

Noticed this problem when setting engines up on the test stand that once the engines were ready to install if they stood with no fuel in the fuel lines and pump(s) while waiting to be installed in the trucks the pumps would not work when installed. In that case the solution seems fairly simple when I finish running the engines in on the test stand make sure the gas line and pumps are left full of gas and plug the end. On the test stand I use an electric pump and when done with test runs with fuel in line just loop the outlet back to the inlet side. Have also tried squirting some oil into the pump but the jury is still out on does this work.

Cheers Phil

[rob love]

It was the same in the pre-ethanol days. I bought a few of the best Jeeps for the least amount of money back in the day when the crown assets guys couldn't get them to go. Once they were in my posession, a squrt of fuel into the pump to wet the checkvalves did the trick.