B1700HST fuel issue?

[pvk]

Newcomer here to these boards looking for some advice/assistance. I just purchased a new to me b1700 hst tractor a couple of weeks ago w/1060hrs on it.

The problem that has started occuring last Saturday is the tractor is starving for fuel I am thinking. When I have her shutdown the fuel bowl is full, then after running the tractor @ idle or higher after 1-2 min. the bowl drains the gas down to the bottom and the tractor almosts stalls, then rev's back up again and runs poorly.

I pulled the fuel filter out which looks fine, I drained the gas and there was no water in it and it was clean...I am loosing my mind! The bowl never fully fills up with fuel again until the tractor is shutdown, then the process repeats itself after 1-2 min.

Anybody have the answer to this riddle?

 

[cmorningstar01]

I would check to make sure there is not sediment/moisture/debris in the tank that is being sucked into the outlet, If the tank is clean then check to make sure your fuel line is not collapsing , If the fuel line is collapsing it could be that the line has lost its rigidity or that the vent in the fuel cap is not allowing air to enter the tank as fuel is being drawn from it. To check the fuel cap simply loosen the cap and run the tractor to see if the problem is resolved.

 

[pvk]

I would check to make sure there is not sediment/moisture/debris in the tank that is being sucked into the outlet, If the tank is clean then check to make sure your fuel line is not collapsing , If the fuel line is collapsing it could be that the line has lost its rigidity or that the vent in the fuel cap is not allowing air to enter the tank as fuel is being drawn from it. To check the fuel cap simply loosen the cap and run the tractor to see if the problem is resolved.

The problem still remains, sediment bowl is full, it empties out, then the drop in rpm's(500rpm's) sounds looks like it is gonna stall, after 10sec it kicks back up to 1700-1800rpm's then sputters down again, loosening gas cap has no effect.

 

[cmorningstar01]

Did you check to see if the fuel line is collapsing, If the bowl is full and then empties out there has to be a reason and the problem would seem that it is most likely somewhere between the tank and the sediment bowl.

 

[pvk]

Did you check to see if the fuel line is collapsing, If the bowl is full and then empties out there has to be a reason and the problem would seem that it is most likely somewhere between the tank and the sediment bowl.

I'll try bleeding the injectors tomorrow to see if this resolves the issue along with replacing the fuel/air filters too.

I'll go to the local auto parts store and replace the fuel line from the tank to the bowl to rule out that too.

Thanks for the help, it's appreciated!

 

[birddogger]

Just so you do not overlook the obvious or bizarre. I saw the exact problem you have, it was a couple dead stink-bugs sloshing around in the fuel tank, occasionally blocking the outlet.

 

[pvk]

Just so you do not overlook the obvious or bizarre. I saw the exact problem you have, it was a couple dead stink-bugs sloshing around in the fuel tank, occasionally blocking the outlet.

Since the tank is a black plastic, any easy way of seeing what else is lurking in the tank. I tried with my work light but it's not strong enough.

A kubota mechanic buddy of mine mentioned a air/vapor lock which is causing the bowl to drain then the engine is sucking in air instead of gas, so bleeding the injectors might do it.

I haven't had the time to do it today since work was hell on wheels, I am hoping bleeding the lines will resolve it. When I emptied the tank the other day, gas flowed out of the fuel line with a nice and steady stream and no blockages.

If this doesn't work the mechanic buddy is coming over to figure this one out.

--pvk

 

[cmorningstar01]

A kubota mechanic buddy of mine mentioned a air/vapor lock which is causing the bowl to drain then the engine is sucking in air instead of gas, so bleeding the injectors might do it.

Bleeding is often required if the tractor has been run out of fuel, Did you run out of fuel and refill before this phenomenon occured, If so then it is very likely that bleeding will solve your problem.

Just one note, In Your posts you refer to fuel as "gas", I am guessing that you are using the term gas to refer to diesel fuel and not gasoline as using gasoline in a diesel engine is not recommended.

 

[pvk]

Bleeding is often required if the tractor has been run out of fuel, Did you run out of fuel and refill before this phenomenon occured, If so then it is very likely that bleeding will solve your problem.

Just one note, In Your posts you refer to fuel as "gas", I am guessing that you are using the term gas to refer to diesel fuel and not gasoline as using gasoline in a diesel engine is not recommended.

The tractor had a 1/2 full tank when this started to occur. I drained the fuel tank again today, checked to see if anything was hanging out inside the tank and it had no bugs, twigs, nuts or anything that would cuase it to block

I proceeded to refuel it with diesel fuel, bled the lines and it happened again!!!!!!!!!!!!.

I am beyond stumped now. Clean tank, fuel, bled injectors, what gives?

I am gonna take a rpg to it shortly.

 

[birddogger]

Do you have compressed air to blow out the fuel line? or maybe run a coat-hanger through it just to make sure that it's clear.

 

[pvk]

Do you have compressed air to blow out the fuel line? or maybe run a coat-hanger through it just to make sure that it's clear.

I replaced the fuel filter today and it runs again, but still stalls on hills for some reason, it seems like the $3.20 filter solved it somewhat.

I don't have a compressor, but a fuel line is a lot cheaper to buy also.

On the b1700, do I have to bleed the fuel injector pump and loosen the air vent plug on the fuel filter body also to get the air out of every little nook and cranny?

1. Fill the tank with fuel and open the cock (4).
2. Loosen the air vent plug (3) of the fuel filter a few turns.
3. Screw back the plug when bubbles do not come up any more.
4. Open the air vent cock (5) on top of the fuel injection pump.
5. If equipped electrical fuel feed pump, turn the key to AC position
and pump the fuel up for 10 to 15 seconds.
If equipped mechanical fuel feed pump, set the stop lever on stop
position and crank the engine for 10 to 15 seconds.
6. Close securely the air vent cock after air bleeding.

 

[birddogger]

but a fuel line is a lot cheaper to buy also.

I was gonna say that, thought about it but guess I forgot.

It is a gravity feed to the filter bowl, the fuel pump delivers to the injector pump but most fuel gets pumped right back to the tank. That's why the bowl goes empty, the engine isn't burning all that fuel that fast.
If there is free flow to the filter bowl this should work.
If there isn't grass, leaves, bugs or ducks in the tank, that leaves the fuel line. Make sure is has a downward slope with no loops to cause an air bubble.

Since I just had a situation with a kill-switch someone, ehem, "bumped" I'd say check the fuel valve position, they are marked in Japanese and I always get on/off mixed up. The tractor that had the stink-bugs in the tank you could not tell much difference between on/off since it flowed in both positions, just a little more in the right position. With the in-feed (from tank) fuel line off the filter bowl it should have a stream like a Clydesdale taking a leak.

 

[pvk]

I was gonna say that, thought about it but guess I forgot.

It is a gravity feed to the filter bowl, the fuel pump delivers to the injector pump but most fuel gets pumped right back to the tank. That's why the bowl goes empty, the engine isn't burning all that fuel that fast.
If there is free flow to the filter bowl this should work.
If there isn't grass, leaves, bugs or ducks in the tank, that leaves the fuel line. Make sure is has a downward slope with no loops to cause an air bubble.

Since I just had a situation with a kill-switch someone, ehem, "bumped" I'd say check the fuel valve position, they are marked in Japanese and I always get on/off mixed up. The tractor that had the stink-bugs in the tank you could not tell much difference between on/off since it flowed in both positions, just a little more in the right position. With the in-feed (from tank) fuel line off the filter bowl it should have a stream like a Clydesdale taking a leak.

Finally got it up and running correctly..I replaced the return lines from the injector pump back to the tank and its been running great, no hiccups, no dying down/up a hill.

When I pulled the return lines out, they had all kinds of blue junk in the fuel tank side( mechanic buddy said it is algae from diesel fuel and condensation).

So I used some algae killing stuff, flushed the tank again, filled er up with diesel to the brim, installed the new return lines and voila!!!!

The wife still loves me, I think. I would like to say thank you for your help, hopefully if this ever happens again, I know where to come to.

--pvk

 

[birddogger]

YAY! glad to hear it is back to normal, and for only a couple bucks of tubing.
Still a little puzzled that the return line would cause it. I would understand if the blue goo was in the supply side, but the return?
Oh well, that's one for the books.

 

[pvk]

YAY! glad to hear it is back to normal, and for only a couple bucks of tubing.
Still a little puzzled that the return line would cause it. I would understand if the blue goo was in the supply side, but the return?
Oh well, that's one for the books.

The only thing I could think of was that it wasn't creating a vacuum?? The tank still had gas in it so gravity forces the gas into the fuel bowl..hmmm. ALl I know is that it is humming along nicely.

Does anyone know where the suction filter is on this b1700hst? I see the hydro filter, but the suction filter is impossible to locate.