MF-50 Diesel - kill switch "return spring?"

After being pulled out (to kill the engine), the kill switch does not return on its own as it is supposed to.
I found this out after nearly ruining my starter trying to get it to crank only to find that the kill switch was in the pulled-out position. How frustrating!

How do I fix this and with what?

Thanks, Coyote
 
After being pulled out (to kill the engine), the kill switch does not return on its own as it is supposed to.
I found this out after nearly ruining my starter trying to get it to crank only to find that the kill switch was in the pulled-out position. How frustrating!

How do I fix this and with what?

Thanks, Coyote
This is the 1963 MF50, you have posted about over several years, correct?

Most fuel shutoff rods, or cables, (there is not a switch on your MF50) have to be pushed back in, they do not self-return. It would be a safety issue if someone let go of the knob as the stopping engine was making its last roll, the shutoff returned itself to the run position and the engine restarted. The rod/cable should stay in the shutoff position until manually reset by the operator. Here is what the Operator's manual tells you:

MF50.jpg

used red MN gave you a link to the parts catalog in one of your other threads. Do you have a copy of the Operator's Manual (MF # 690525M1) and a copy of the Service Manual (MF#1448811M1)? If not, you should get them, you will likely have to purchase those. (Note the base number is important, the suffix number after the M may vary with the printing.)
 
Jim,
Yes, it's the same tractor. Based on what you found in the manual, I guess my Papa added a spring on it that the recent mechanic removed - Since I've owned it, the rod would return on its own. And yes, sometimes I'd let go too early, but we only shut it down at a stand still.
But, I see your point about a safety issue. I guess, my whole family is just used to it returning on its own, so we'll just need to get used to pushing it back and double checking it before we crank the tractor.

My wife is concerned that the rod would vibrate out of the "run" position and the tractor would die at a less than convenient time. We have a lot of steep hillsides, and losing power at the wrong place would be bad. We'll see how it goes.

Thanks for pointing out the operator's and Service Manuals.
Merry Christmas, Coyote
 
Jim,
Yes, it's the same tractor. Based on what you found in the manual, I guess my Papa added a spring on it that the recent mechanic removed - Since I've owned it, the rod would return on its own. And yes, sometimes I'd let go too early, but we only shut it down at a stand still.
But, I see your point about a safety issue. I guess, my whole family is just used to it returning on its own, so we'll just need to get used to pushing it back and double checking it before we crank the tractor.

My wife is concerned that the rod would vibrate out of the "run" position and the tractor would die at a less than convenient time. We have a lot of steep hillsides, and losing power at the wrong place would be bad. We'll see how it goes.

Thanks for pointing out the operator's and Service Manuals.
Merry Christmas, Coyote
If the injection pump is right internally, the rod will stay in position. If the rod moves on its own, your pump needs to be looked at.
 
After being pulled out (to kill the engine), the kill switch does not return on its own as it is supposed to.
I found this out after nearly ruining my starter trying to get it to crank only to find that the kill switch was in the pulled-out position. How frustrating!

How do I fix this and with what?

Thanks, Coyote
My 65 diesel doesn't have a return spring. I don't think they ever did.
 
After being pulled out (to kill the engine), the kill switch does not return on its own as it is supposed to.
I found this out after nearly ruining my starter trying to get it to crank only to find that the kill switch was in the pulled-out position. How frustrating!

How do I fix this and with what?

Thanks, Coyote
My 65 diesel has this device on the fuel shutoff rod right behind the knob. It is "springy" and keeps the rod in whichever position it is set at. Seems like your 50 should have the same thing.
1735071505165.png
 
My 65 diesel has this device on the fuel shutoff rod right behind the knob. It is "springy" and keeps the rod in whichever position it is set at. Seems like your 50 should have the same thing.
View attachment 98496


Yep.

I looked for a online pic of that yesterday to post but couldn't find a clear, concise one.

Didn't think there was much point trying to explain it without a good pic. Picture, thousand words, you know how it goes.
 
Yep.

I looked for a online pic of that yesterday to post but couldn't find a clear, concise one.

Didn't think there was much point trying to explain it without a good pic. Picture, thousand words, you know how it goes.
That bracket and spring shows for the shut off rod for the direct injection engine, the regular diesel used a different rod and spring arrangement according to the 65 parts book. The 50 parts book only shows a cable, not a* rod like the 65.

I guess the first question is does wayacoyote's MF50 have a cable or rod for a "kill switch"? Mabe a picture of what he has would help along with a few if the tractor in general.

edit to add "not a*"
 
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That bracket and spring shows for the shut off rod for the direct injection engine, the regular diesel used a different rod and spring arrangement according to the 65 parts book. The 50 parts book only shows a cable, not a* rod like the 65.

I guess the first question is does wayacoyote's MF50 have a cable or rod for a "kill switch"? Mabe a picture of what he has would help along with a few if the tractor in general.

edit to add "not a*"


Yeah, I figured there were some different types from the pics I found.

You say "regular diesel and direct injection diesel". Do the Perkins engines have both, or is the "regular diesel" the Standard engine?

I don't have a lot of experience with diesels.

I guess I answered my own question, I checked on Tractordata and they say the Perkins is the only diesel in a MF 50.
 
Yeah, I figured there were some different types from the pics I found.

You say "regular diesel and direct injection diesel". Do the Perkins engines have both, or is the "regular diesel" the Standard engine?

I don't have a lot of experience with diesels.

I guess I answered my own question, I checked on Tractordata and they say the Perkins is the only diesel in a MF 50.
I think the regular diesel was the Perkins indirect injection vs the later Perkins direct injection engine. Dieseltech or one of the other fellows may be along with a better answer. I think the indirect engine injectors were on an angle in the head and the direct engine ones are straight down.

edit: Looks like I got that backwards indirect injectors are straight down in the head, direct go in on an angle.
 
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It turns out that mine looks like Bob's picture, except that the "springy thing" is broken. I had always wondered why there was a stiff wire around the pull knob. Seeing Bob's picture explains it all.
Thanks.
 
It turns out that mine looks like Bob's picture, except that the "springy thing" is broken. I had always wondered why there was a stiff wire around the pull knob. Seeing Bob's picture explains it all.
Thanks.
You're welcome. Maybe someone who is good with the online parts book can find out if that piece is available.
 
You're welcome. Maybe someone who is good with the online parts book can find out if that piece is available.
Below is what the online parts book shows. I added the darker green notes and the bracket part number so they would be in the picture. I just used a random ecommerce dealer. wayacoyote will have to check with his dealer but it looks like AGCO still has the spring.

Capture.JPG
 

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