Fuel?

[Mike Rock]

My Bobcat 743 is developing a fuel issue. After ten minutes or so, it appears to run out of fuel. Bleeding the air valve helps it start but it still seems to run out of fuel every so often. A few times it keeps running after warming up. I replaced the fuel filter, suspecting water after the long winter. What is happening? Any further clues to look for?​

God bless,
Mike Rock

 

[brdgbldr]

My Bobcat 743 is developing a fuel issue. After ten minutes or so, it appears to run out of fuel. Bleeding the air valve helps it start but it still seems to run out of fuel every so often. A few times it keeps running after warming up. I replaced the fuel filter, suspecting water after the long winter. What is happening? Any further clues to look for?​

God bless,
Mike Rock

Could be your fuel pickup tube is cracked or broken sucking air when the fuel level gets below the crack or break.

 

[Mike Rock]

Darned good answer. 31 year old tubing..... just had the cab raised today to replace the shutoff cable, raise it again tomorrow. Sounds great, just like old Stihl chainsaw fuel pickup, my 041's all need new hose. Thank you so much. God bless.

 

[mrbb]

could also be you have a dirty fuel tank, and as it runs it sucks up debris and clogs filter or flow enough to cause running issue, then as it sits a bit debris falls /no longer blocking flow, until you run some moire and repeat! 30 yrs, lots of time for bad fuel or dirt to get into a tank!

 

[Mike Rock]

Is there a screen filter on the pickup end in the tank? Like a chainsaw? We'll pull the pickup hose today, after fixing the brakes on the Super M.

 

[brdgbldr]

Is there a screen filter on the pickup end in the tank? Like a chainsaw? We'll pull the pickup hose today, after fixing the brakes on the Super M.

Yes, there should be a fuel pickup screen on the end of the fuel line.

 

[Mike Rock]

Bridgebuilder..... pulled the tank. Had three electrical wires corroded off inside the two multi plugs we had to take off to the tank loose. It wouldn't come without moving that piece of iron between the hydraulic tank and the fuel tank. Anyway...... let's start Vegas odds on how much crap was in the tank...... almost covered the bottom of a five gallon white plastic bucket. Glad we left the fuel in the tank, fought it with ten gallons...but it cleaned out the fuel tank just fine. 1/8 cup or so of crap.
The two filters were plugged tight, had to fire up the air compressor and clean them. One, the suction side, has a check valve, the return line has just a screen. I'm going to cut the NEW plastic fuel line so it hangs an inch off the bottom. The return line will touch bottom.

Thanks for the suggestion!! Wife will be back with hose in an hour or so, we'll be back up by tomorrow, after jumpering around the broken wire connections.

God bless,
Mike Rock

 

[Mike Rock]

Holy cats.......it's a brand new Bobcat. It even sound different, gutsier...... started in one crank after pumping the primer bulb a bit.
Thank you all so much, especially Bridge Builder )
God bless,
Mike Rock

Oh, a farmer friend stopped by....showed him the buckets with the fuel/dirt mix. He said,"Don't buy fuel in Argyle, one Diesel tank is full of that crap." Well, that's 31 years of fuel from that source and the dirt showed. The Bobcat place said the same thing when I called. Oh well..

 

[reaperman]

Im surprised your machine ran at all. Glad it fixed!

 

[mrbb]

yeah 31 yrs is a lot of time for a machine that tends to work in dirt and dusty environments, which is why I said, odds are high the inside of tank was contaminated and causing you potential issues

even algae is a common problem in many locations inside fuel tanks these days!

also a good reason to use fuel cans with screens in there spouts(if you fill from cans that is, it helps catch some of the crap in fuel stations tanks
not to mention doesn't hurt to add a decent fuel additive now and them too,

 

[Gbannish]

Could be your fuel pickup tube is cracked or broken sucking air when the fuel level gets below the crack or break.

There's a really good video on youtube from tetradgroup about how to replace the pickup tube with screen. I did it years ago, and it was easy after following his tips...