Well guys, I need some advise. Kinda long.

Adirondack case guy

Well-known Member
My 1957 310 dozer is giving me fits. I bought everything from John and Chris to overhaul the 148, including new valves and guides. Took the head to local engine shop and they also replaced seats, rotors and different stem seals they recomended.
The problem is the fuel delivery system. The old MOPAR impuls fuel pump died, and years back I had bought a replacement Carter, rotary multi Voltage pump for it. ( never installed) Found that a couple of wacks with a cresent to the old pump would get it ticking again, but was a no go after overhaul. Still using a 6V system. I replumbed everything, with the Carter pump,-- got fuel to the carb,. and the 148 came to life instantly, but soon flooded out. The float could not stop the gas flow. I spent some time on the computer and found an Airtex 6V impulse fuel pump which speced at 5-8# of pressure, and description said for use in carborated engines. Well this Airtex pump does the same thing. I have taken the carb off several times, and adjusted the float bulbs lower in the bowl, with no improvement. I then cut a 3/8" steel slug and drilled it with the tineyest drill bit I had and slid it into the rubber gas line to restrict flow. It still overpowered the float. Tomarrow I will buy a carb kit for the MS carb., with hopefully a rubber tiped check valve. I can't find anything wrong with the seat or check in the carb now, but will see if new seat and check solves problem. If not I Have come up with a way to install a return line to the steel tank under the seat, but a bit aprihensive about drilling a hole in the tank with my drill to thread a return line into. I suppose I could also plumb the return line back into the supply line from sediment bowl to the pump, with the slug I made in it also.
What would you guys do?????
Loren.
 
I would start by putting fuel pressure regulator on it. Even if it says the pressure is suppose to be the same it may not. I have had the same thing happen on pickups. I always get a regulator that has a port for a gauge. just my thoughts on it.
 
https://www.pegasusautoracing.com/group.asp?GroupID=FACET

Go here......great selection of pressure ratings that would work better. The 1.5 psi max is possibly what you would need.
 
CARQUEST used to have a little squareish tick tick pump and an inline regulator that would go as low as .5psi....I believe it was a Purolator brand name on it..it worked great with a pair of mikuni side drafts back in the day.
 
Recommend getting a low pressure electric pump if you can. Neighbor had the same issue with a forklift; pump put out 7 PSI and kept it flooded. Put on a 1.5 PSI model and problem solved.

I have a '65 Mustang I'm restoring and it's fighting the same battle but has a factory carb and pump. Looks like I'm going to need an inline regulator. Hopefully the link will come through below and it doesn't need a return.

Hope this helps.

Ken in AZ
regulator
 
Check out some of the old car parts websites. I had issues with a fuel pump on a 49 Buick Super and while I sent the original off to have it rebuilt (double-diaphragm pump)I found a mail-order place that had a 6v electric tick-tick pump pretty cheap--- 25 yrs ago, I think it cost me 22 bucks with shipping. The nice part of it was, it had a allen-head screw deal that you could back out to lower the pump pressure to almost 0. It took a little trial and error, but after 3 tries I got it set just right. I was surprised how well the old girl ran with proper fuel flow. I had been fighting that original pump for years. After I got the original back on the car, a neighbor had a fuel pump go out on his 715 combine in the field running wheat. I put that 6v pump on it with one of those little ceramic semi-circle voltage reducers, and I think it's still on it. This was, of course, before everything was built in China.
 
I have worked on a 350 case dozer from the same year with the same problem. You must get a pump which produces less than 1.5 psi (preferably 0.5 psi or less) at the back side of the needle when the engine is at idle. Otherwise it will flood out. Also, a system which uses a cheap electric fuel pump with a restrictor will not work at idle unless you have a return line. The restrictor restricts flow, not pressure. Thus, the restrictor becomes ineffective when the flow through the line is low, and it will still push the needle down at low rpm. You need to have constant flow through the restrictor to keep up the constant pressure drop (hence the return line). The engine driven pump is a much better solution because it produces low pressure and flow at low rpm, and high pressure and flow at high rpm. Either get an engine driven pump, regulator/restrictor with return line, or go to gravity feed.
 
Check Facet's website , I got one from them through Napa for my 930CK gas. I don't remember all they offer but it was quite a selection.
 
Loren,I have ran in to that pressure problem also with a new Airtex or a Facet pump I don't remember what one.On a air compressor and a Goodall Startall both hooked to a outboard boat fuel tank in the back of a service truck.Take the fittings out of the pump and shorten or replace the spring that holds the seat ball and that will lower the fuel pressure.You could even weaken the spring some with a propane torch.
 
Dear Mr. Caseguy,
It sounds like you have a tough problem there. I recommend that you sell that little thing to a certain someone in Minnesota. The cold air and relative low barometric pressure in Northern MN would make that thing run like a top!!!!:} Hope you get it figured out!

Bryan
 
I had a recent similar experience with an old gehl skid steer, gas engine with MS carb and mechanical fuel pump. The old carb was shot so I bought a rebuilt one from all states ag parts. Well since I did that the carb would always flood out no matter how I had the float set. I got my original carb back and it turns out there was a little helper spring in that one which helps the float push the needle up. This was only used on machines with fuel pumps. So I wonder if you could add a spring to yours to help float shut off fuel flow.
 

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