Engine 721D won't start

lsrichardson · May 22, 2017

I just recently bought a Grasshopper 721D with 1500 hours on it. I've used it a few times - 5-6 - without any issues. My son has pulled it out of the garage to work on his dirtbike. this last time he pulled it out, then when we went to start it, it turns over but won't start, no matter how long we use the glow plugs. It was towards the low end on fuel - just above empty.

cpurvis · May 22, 2017

How do you normally shut this engine off? With the key or with a manual fuel shut-off?

173abn · May 22, 2017

if it's low on fuel could be some crud in the tank clogging up the line...russ

cpurvis · May 22, 2017

That's one of the cardinal sins of diesel engine operations--running low on fuel. Because that invariably leads to running out of fuel and diesels really don't like that.

lsrichardson · May 22, 2017

i shut the mower off with a key.....

about the fuel, it was showing the symbol just above the empty indicator

cpurvis · May 22, 2017

Can you verify that the fuel shutoff solenoid is working? i.e., getting voltage; making a 'click' sound.

What the fuel gauge shows could possibly be in error.

It only takes heat from compression and fuel to make a diesel run. If the engine was getting fuel and not starting, puffs of white smoke (unburned fuel) would be coming out of the exhaust.

173abn · May 23, 2017

I would put some fuel in it and bleed the system.fairly easy to do on a GH.Do you have a manual,if so it tells you how to do it...russ

lsrichardson · May 24, 2017

don't have a manual....

bought it used, sent email to grasshopper requesting a manual and all they sent me was a SL98 mower deck manual

tried bleeding system, doing the following..

opened up the bleeder screw on the side of pump and blew pressurized air through the tank until fuel came out - a lot came out - then tightened bleeder screw

then loosened the nuts on the injectors and turned it over. it looked like maybe some fuel came out - definitely didn't squirt out like I've read in various places

When I turn the key to the start position, the solenoid moves....

When I turn it over it occasionally acts like it wants to fire.

cpurvis · May 24, 2017

It's a Kubota engine, isn't it? Look here: https://www.youtube.com/watch?v=XJn2kDnWQPU

bertsmobile1 · May 24, 2017

Time for the either.
Get a can, warm it up ( sit in the sun ) then give the engine some short shots down the air intake.
When it fires keep giving it short shots till you get a real rich black exhaust, indicating that the cylinders are getting deisel and the either you are squirting in.
Running a deisel dry andgetting the injectors to start squirting fuel in can take a lot of time & cranking thus stuffing the starter , draining the battery & cooking the power cables.
Some squirt down the air intake does the same job with a lot less stress on the mower.
Modern deisel ( well what we get down here ) is only good for 90 days then it picks up water like you would not believe , becomes tacky ( sticky kind ) and gums up the pump.
We have to run all of the deisels on the farm for at leas a hour every month or so till the fuel in the tank gets hot to evaporate the water.

Engine 721D won't start

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lsrichardson

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cpurvis

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173abn

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cpurvis

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lsrichardson

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cpurvis

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173abn

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lsrichardson

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cpurvis

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bertsmobile1

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