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I got a 706 with the 282 diesel in it. I have noticed that when accelerating or decelerating there is a noticeable and sizable delay in moving the throttle and the engine reacting to the input. When decelerating rapidly the engine will die but if you slowly return to idle it will idle fine. Am I looking at a injection pump issue or injectors? 

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sounds like the metering valve inside pump is sticking. Try running fresh fuel with a good quality cleaning additive. Run it at a medium speed, and work throttle back and forth to try to free it up. If it has a shut-off cable, pull it out and push in, but most 706 had single lever shut off. 

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yes those dang things get a little tacky sometimes - i had issued with mine like that off/on and what he said worked to get mine going, it sat a lot - course it was on a 560 but same setup - roosamaster - using it made it better 

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Back in the early days of the Roosa Master on the 4 & 560. 706 etc., the metering valve would wear the point off the tip of the valve where it rides up against the governor guide stud.  I think Roosa changed the material two or three times but you can still get a flat spot and that will do what you are describing.   I replaced a lot of metering valves and guide studs in those early years.  

I would unhook the throttle linkage and very carefully move the lever on pump to determine if it had nice even response.  Also, the load advance pumps would change the advance as metering valve wore into the taper on those guide studs. A slight turn of guide stud to new spot would often get advance working properly again.

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Sounds like a governor issue to me if it doesn't come out of it it will need taken off and repaired at a diesel pump shop

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3 hours ago, ksfarmdude said:

Sounds like a governor issue to me if it doesn't come out of it it will need taken off and repaired at a diesel pump shop

The metering valve is a very intricate part of the governor. 

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7 hours ago, pete23 said:

The metering valve is a very intricate part of the governor. 

My 656 did something similar to his problem and I took it to my local pump shop they got me going again works great now

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I'm gonna try some additive first, can't hurt right. Then if that doesn't work I'll send it off. But I need to find a good pump shop near nc

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Not a 706 but case 580 backhoe started the same thing and found out the pump was junk inside, plastic parts inside went south and messed up the whole pump! ---tractor still sitting because of that

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Hope it works  I've never had any luck using snake oil remedies 

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ya know now that i think of it, i had done some tinkering on my pump about the same time i put in the additives i cant remember now what i tweeked on that roosamaster ( you guys told me here ) seemed like u guys had me turn 3 different things.......and it was doing it a couple times after that then it quit and never did it again - maybe it was the adjustments, maybe it was the fuel stuff ( snake oils ) i will say it ran better after i adjusted those things - throttle response was quick, a little more smoke and it idled better 

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On 4/29/2020 at 7:24 PM, pete23 said:

Back in the early days of the Roosa Master on the 4 & 560. 706 etc., the metering valve would wear the point off the tip of the valve where it rides up against the governor guide stud.  I think Roosa changed the material two or three times but you can still get a flat spot and that will do what you are describing.   I replaced a lot of metering valves and guide studs in those early years.  

I would unhook the throttle linkage and very carefully move the lever on pump to determine if it had nice even response.  Also, the load advance pumps would change the advance as metering valve wore into the taper on those guide studs. A slight turn of guide stud to new spot would often get advance working properly again.

Being a novice at injection pumps can this be done on the tractor, and what is involved in doing this. I am fairly good turning wrenches but have never been in an injection pump before

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Yes it is done on tractor.   Requires removal of top cover, throttle shaft, guide stud and metering valve.  If you do replace the metering valve you have to also remove the arm from it along with spring and washer.   Touchy work as a miss step can cause engine runaway.  

I would take timing cover off first and look for any contamination like coffee ground size plastic.  Then you know pump would need to be repaired. 

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I never try messing with them pumps on my own if they have boo-ko hours I take it to  the pump shop for repair  30-minutes to remove box it up and its gone never had a bad pump fix job yet I have more important thing to do than tinker with a piesa crap pump that won't perform

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There is a plastic disc in the governor that fails after a half a century or so. When it fails completely the pump goes to wide open and the throttle won't shut the fuel off. Can we say "grenade?" Do  not run it, take the pump off and get it rebuilt. My 706 did the same thing. Cost me 1200 bucks.

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8 minutes ago, R Pope said:

There is a plastic disc in the governor that fails after a half a century or so. When it fails completely the pump goes to wide open and the throttle won't shut the fuel off. Can we say "grenade?" Do  not run it, take the pump off and get it rebuilt. My 706 did the same thing. Cost me 1200 bucks.

Wow twelve hundred bucks ? sounds very high to me most I ever spend on those is 5-to 6 hundred and that's if they need major repair

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2 hours ago, pete23 said:

Yes it is done on tractor.   Requires removal of top cover, throttle shaft, guide stud and metering valve.  If you do replace the metering valve you have to also remove the arm from it along with spring and washer.   Touchy work as a miss step can cause engine runaway.  

I would take timing cover off first and look for any contamination like coffee ground size plastic.  Then you know pump would need to be repaired. 

When you say look under the timing cover, I assume you mean to remove the top cover of the pump and look in where the metering valve is. Not where the timing gear is on the front of the motor

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52 minutes ago, 885 said:

When you say look under the timing cover, I assume you mean to remove the top cover of the pump and look in where the metering valve is. Not where the timing gear is on the front of the motor

No, the timing cover is that little cover on the side with two screws.  Crud will collect there if a problem with governor flex coupler failure. 

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Is that a dry area or is that cavity fuel filled. I guess I'm asking if there is a gasket that will need to be replaced after inspection

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31 minutes ago, 885 said:

Is that a dry area or is that cavity fuel filled. I guess I'm asking if there is a gasket that will need to be replaced after inspection

Full of fuel but normally can reuse gasket .    

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On 5/1/2020 at 6:04 PM, ksfarmdude said:

Wow twelve hundred bucks ? sounds very high to me most I ever spend on those is 5-to 6 hundred and that's if they need major repair

Yeah, well, I am a Canadian so everything is **** for expensive up here. That cost was for a full overhaul, the guy said after 50 years it would need it anyway.

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OK so I got an update for you guys. I put additive in and thought why not we will give it a shot. We had a little break in the weather and even though it was early we mowed and baled some alfalfa. I put the 706 on the baler and it behaved fantastic so I guess I dodged the bullet for now. The throttle response is perfect. The only thing now is I need to adjust/fix a little slop that I must still have in the linkages. When the throttle lever is on the idle stop it will die. I have to set the throttle lever forward a little to let it idle and it idles very smooth. I am getting full rpms at wide open or so it seems, it will go over pto speed to about 2400 on the tach, which seems right from what I have read. So something seems to be out of adjustment somewhere. 

IMG_20200503_152253662.jpg

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I just went though this with my 706, so I know what you are dealing with.  The snake oil additives will help for a while, but unfortunately you are just prolonging the inevitable.  It got me through hay season, but by fall it became worse and REALLY annoying to have it quit every time you throttled back.  I figured if it can stick at idle, it can stick at full fuel and run away, so I just choked up the $1000 and had mine rebuilt.

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I figure it's just buying me some time. Mine actually doesn't quit when throttling back. It seems as though the linkage is out of adjustment as to the relation to the idle stop location. At least that's the way it seems to me at the moment. I figure I should go ahead and get the pump rebuilt but my problem is there are no places to get pumps rebuilt anywhere remotely near me. And the closest pump shops in the neighboring states are not highly thought of from what I hear. I don't know who to go to, or who to send it to

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On 4/30/2020 at 8:25 PM, ksfarmdude said:

Hope it works  I've never had any luck using snake oil remedies 

Lubricant is not snake oil.Fuel does not have enough lubricant in it now since it is very low sulfur.I use Howes in all my diesels since I had metering valve trouble in one of them.I look at it as a part of a good maintance program.Why wear things out when you don't have to.

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