New here with questions

[Azmotorhead]

Hello all.
I have a old John Deere 650 with a Yanmar 2T80 engine.
I was running great till the a day ago. It just slowly died like it was running out of fuel. Still had 2 gals in the tank.
Fuel filter was very dirty so I changed that,changed air filter, drained and cleaned out fuel tank.
Replaced rubber fuel lines. Filled with fresh fuel.
Made sure I had good flow to the Inj pump. cracked lines at the injectors to make sure I had good fuel flow.
Then tried to restart. It fired up but immediately went to WOT and was unresponsive to throttle lever. Emmitting thick black smoke.
Would not even cutoff with key off and throttle fully retarded.
Had to kill engine by pinching fuel inlet hose. Then I reset/adjusted the Hi idle stop. another restart and same results. WOT no cutoff and thick black smoke.
I'm thinking I have a injector stuck open.
Does this sound about right?
Where can I obtain service parts?

 

[deerseeker001]

Welcome from Wisconsin,post this in John Deere forum on the home page.

 

[Tx Jim]

Faulty injector is not causing WOT but a faulty governor probably is.

 

[Azmotorhead]

Thanks, for the input so far.
Tx Jim, I'm ruling out the govenor for a couple of reasons.
1 when it first died it died slowly like it was starved of fuel. Throttle input couldnt keep it running.
2 Excessive black smoke when it does run now. indication of a over enrichment.
3 I didn't mention before,while cranking it over. Before it catches and starts it has greyish exhaust. unburnt diesel fuel.

 

[mikehaugen]

Well not shutting off indicates an issue with fuel solenoid. Is it possible the throttle is just sticking? Because of the governor, the lever is not directly linked to the throttle.

 

[Azmotorhead]

Through the inspection window(motor off) I can see the throttle lever and how it moves the slide on the injection pump.
Everything visible through the inspection window moves freely

 

[Oldtink]

I'm with Tx Jim and wouldn't be so quick to disregard the governor.

 

[fieldman12]

I agree with Texas Jim on the govenor most likely the issue.

 

[tomd999]

Hiya,

The no throttle control is called "a runaway". They are caused 2 ways, either by a combustible being present in the air that the engine draws in and this adds to the fuel in the cylinder, when you kill the Diesel to the engine, it keeps running. This type is very bad as there is no governor control and the engine can overspeed and damage parts. The only way to stop these is to either block the air from entering the engine physically or to introduce co2 into the intake to stop the combustion process. The second type is by a governor or injection pump failure or mis-adjustment. When people "turn the screw" to add fuel to an engine, there is a point where the fuel cam will not return to idle position and the engine runs up to the governor. If you have turned the screw, back it down to where is was and see if that fixes it. Another possibility is that the injection pump has failed and the fuel cam is stuck in the 100% position. I have had this happen on rotary Bosch pumps. I have seen pumps break 2 ways, either stuck at idle or 100%. The above posters may be correct about the governor, it may be stuck at full but from the way you said it acted before it died, slowly loosing power and speed and the crud you said you pulled out of the fuel system, I'm thinking you'll find some issue with the injector pump.

My 2 cents,

Tom

 

[Oldtink]

Thanks Tom, for your input, that makes perfect sense to me.:drink: