North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
B7510 tries to start and smokes but won't run after a fuel filter clog---??? Help?
- Thread starter MWeaver
- Start date
Thank you Wolfman. New pump on the way, will try the direct-to-the injector pump option tomorrow if the weather holds, see if I can get it to start.
Note to Russell King-- smoke intermittent but pretty black when it came out while cranking. I am now wondering if a failing fuel pump might cause that.
Note to Russell King-- smoke intermittent but pretty black when it came out while cranking. I am now wondering if a failing fuel pump might cause that.
North Idaho Wolfman
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Runs With Scissors
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L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
I think you "dodged a bullet" sir.
It has always been my understanding that the starting fluid basically explodes a “long time” (relatively speaking) before it is supposed to due to the high compression ratio of diesels.
Therefore the piston is trying to compress an “explosion” instead of the normal air/fuel mixture.
(unlike a gas motor, where the “explosion” still waits for the spark to happen when ether is used)
The extremely high pressure that this creates, tends to “bend and break” things. (like connecting rods)
No diesel (that I know of) is designed to be “starter fluid friendly”, but it seems that Kubotas are VERY prone to damage.
There may be other reasons, but that has always been my understanding of it.
No diesel (that I know of) is designed to be “starter fluid friendly”,
You’re talking out of your wrong end again. Ive had numerous diesels with ether injection systems on them right from the factory. In fact they dont have glow plugs at all. Cold weather starts happen with ether. Of course these were larger hp engines than kubotas, but just pointing that out to you.
You’re talking out of your wrong end again. Ive had numerous diesels with ether injection systems on them right from the factory. In fact they dont have glow plugs at all. Cold weather starts happen with ether. Of course these were larger hp engines than kubotas, but just pointing that out to you.
Runs With Scissors
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L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
BTW, check your engine oil. Often, when the lift pump diaphragm fails, it pumps fuel into the crankcase, causing an overfill and oil dilution.
Still no go. Help still appreciated.
Yesterday I checked flow from fuel tank, put on new filter housing and filter, cleaned gravity-fed hose to lift pump (good flow), tested lift pump (failed, new one ordered).
Today I checked engine oil (fine), hooked gravity feed hose directly to injector pump, did fountain test with injector lines removed--seemed like injector pump did what it is supposed to do, though I would say not so much like fountains as like squirt guns, rythmically shooting small droplets 2-3 feet in the air .
Blew out and re-installed injector lines, bled air until all three had pulse at the injector inlets. Note:
I did NOT blow air into the injector inlets, not being sure of what good protocol is at these points. If this is ok, I could go back and blow air into them if that would help get any possible crud out??
After bleeding air from lines, tried to start engine. Did get some smoke. But no cough and no start. Smoke was a pretty healthy gray, an improvement in color from a few days ago, possibly because the lift pump is no longer part of the supply system.
Tractor is cool (40-50 degrees), am thinking I will put some heat under it, get temp up a bit and try again.
Might also try bleeding injector lines again with glow plugs removed to increase spin.
Any comments/ideas welcome. I am still baffled.
Yesterday I checked flow from fuel tank, put on new filter housing and filter, cleaned gravity-fed hose to lift pump (good flow), tested lift pump (failed, new one ordered).
Today I checked engine oil (fine), hooked gravity feed hose directly to injector pump, did fountain test with injector lines removed--seemed like injector pump did what it is supposed to do, though I would say not so much like fountains as like squirt guns, rythmically shooting small droplets 2-3 feet in the air .
Blew out and re-installed injector lines, bled air until all three had pulse at the injector inlets. Note:
I did NOT blow air into the injector inlets, not being sure of what good protocol is at these points. If this is ok, I could go back and blow air into them if that would help get any possible crud out??
After bleeding air from lines, tried to start engine. Did get some smoke. But no cough and no start. Smoke was a pretty healthy gray, an improvement in color from a few days ago, possibly because the lift pump is no longer part of the supply system.
Tractor is cool (40-50 degrees), am thinking I will put some heat under it, get temp up a bit and try again.
Might also try bleeding injector lines again with glow plugs removed to increase spin.
Any comments/ideas welcome. I am still baffled.
The mechanical pump should come in tomorrow, from Amazon, so no problem there. I hope.
The problem is that the engine should start now without the pump since I have gravity fed fuel to the injector pump--unless there are still air bubbles in the upper lines bogging things down.
Will try again tomorrow as weather permits.
The problem is that the engine should start now without the pump since I have gravity fed fuel to the injector pump--unless there are still air bubbles in the upper lines bogging things down.
Will try again tomorrow as weather permits.
Russell King
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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
I don’t think that the results of the fountain test are correct. There should be a gush of fuel that is a couple of inches tall (as I understand it). But I am no expert and have never seen a fountain test performed.
@whitetiger happens to be online so perhaps he can comment or perhaps @North Idaho Wolfman will see this when he is online
Last edited:
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
The fountain test sounds fine.
If it's spitting fuel out it's working.
DO NOT blow air into any part of the system, it won't do you any good.
Sounds like you still have air in the system.
If it keeps up, you might need to have the injectors rebuilt.
You could open them up and have a look, just keep all the parts in the same injector and in the proper location and orientation.
If it's spitting fuel out it's working.
DO NOT blow air into any part of the system, it won't do you any good.
Sounds like you still have air in the system.
If it keeps up, you might need to have the injectors rebuilt.
You could open them up and have a look, just keep all the parts in the same injector and in the proper location and orientation.
Wolfman, you are a saint. Question:
That vent line off the injector pump inlet that you mentioned earlier--I just realized my clamp came off after the fountain test and I didn't put it back on when I tried to start the engine. So that vent line was open while I cranked on gravity feed. Would that affect fuel getting to the injectors?
We have a storm today, so not much work likely, but maybe by tomorrow I will have new lift pump.
Dismantling the injectors sounds a but daunting so am hoping won't have to.
That vent line off the injector pump inlet that you mentioned earlier--I just realized my clamp came off after the fountain test and I didn't put it back on when I tried to start the engine. So that vent line was open while I cranked on gravity feed. Would that affect fuel getting to the injectors?
We have a storm today, so not much work likely, but maybe by tomorrow I will have new lift pump.
Dismantling the injectors sounds a but daunting so am hoping won't have to.