Need AR throttle adjustment help

[GregoryU]

I've read a bit about the throttle adjustment on an AR. But I really don't understand how the throttle system works. I push the throttle forward to get full throttle, the engine speeds up, but here's where I lose it. I'm used to a throttle normally hitting a stop...that's it, no more. But on the AR, the spring set up baffles me.
When they say to increase the throttle to fast idle, I assume that means "full throttle? Then what is full throttle? When the engine speeds up, I can push the lever a loooong ways more which actually just bends the flat spring more.
I can't get full throttle without the spring pulling the throttle back and lowering the rpm. I don't see any way on mine to tighten the drag on the throttle lever itself. What am I missing here? I'm just not getting it!

 

[ET]

Fast idle and full throttle to me means high speed no load. There is a cone on the lower end of the shaft that the throttle lever rotates. Downward pressure is applied to the cone by the spring under the throttle lever. This provides friction for the throttle linkage.

 

[a49deere]

my 38' AR has a screw stop on the steering shaft support that limits the throttle handle travel. Don't quote me on this but your high RPM should be around 975, depending on year. you will probably need to get a rpm counter and put it on flywheel to adjust.

 

[a49deere]

this is what ET is referring to. Not sure if you year is the same. I made the mistake of cleaning and lubricating the same on my 44' B and now the throttle is loose and will not stay at the desired speed. Guess i need to clean of lube and let is rust again! Maybe your spring is weak or broken.

 

[Ray,IN]

In the HDT and diesel pusher MH world, high idle is 1,100-1,200 RPM and WOT high limit RPM is about 2,200=2,400, depending on engine type/size. Normal low idle is 600-700 RPM, with 700 being the upper limit.
How that compares to your engine, I don't know.

 

[a49deere]

I've read a bit about the throttle adjustment on an AR. But I really don't understand how the throttle system works. I push the throttle forward to get full throttle, the engine speeds up, but here's where I lose it. I'm used to a throttle normally hitting a stop...that's it, no more. But on the AR, the spring set up baffles me.
When they say to increase the throttle to fast idle, I assume that means "full throttle? Then what is full throttle? When the engine speeds up, I can push the lever a loooong ways more which actually just bends the flat spring more.
I can't get full throttle without the spring pulling the throttle back and lowering the rpm. I don't see any way on mine to tighten the drag on the throttle lever itself. What am I missing here? I'm just not getting it!

View attachment 148787

search, Governor linkage adjustment, in the archives, Clooney explains it well on 9/05/2002

 

[GregoryU]

My old manual shaft center RPM gauge shows about 850 RPM on the flywheel. I can get more RPM's but the flat spring pulls that down.
I can use the set screw to limit the travel but I can't get the RPM's up without the flat spring pulling it back.
I searched the linkage adjustment, but can't seem to get anything to come up before 2015.

 

[a49deere]

My old manual shaft center RPM gauge shows about 850 RPM on the flywheel. I can get more RPM's but the flat spring pulls that down.
I can use the set screw to limit the travel but I can't get the RPM's up without the flat spring pulling it back.
I searched the linkage adjustment, but can't seem to get anything to come up before 2015.

I'm sorry, I googled "governor linkage adjustment on a john deere two cylinder" and the first thing that popped up was "governor linkage adjustment. Click on that and Clooney's comment is like three down from top.

 

[a49deere]

I'm sorry, I googled "governor linkage adjustment on a john deere two cylinder" and the first thing that popped up was "governor linkage adjustment. Click on that and Clooney's comment is like three down from top.

Does your throttle handle move back and for very freely? There should be a fair amount of resistance to keep throttle where you want it. That spring should not pull back the throttle arm if the cone shaped friction area under throttle handle is under pressure of the spring that I showed in my previous post.

 

[greenmech]

My old manual shaft center RPM gauge shows about 850 RPM on the flywheel. I can get more RPM's but the flat spring pulls that down.
I can use the set screw to limit the travel but I can't get the RPM's up without the flat spring pulling it back.
I searched the linkage adjustment, but can't seem to get anything to come up before 2015.

When your throttle is pushed full distance the rod to the carburetor should be a half hole short of going in the hole. In other words it should take a little effort to line it up. Ron MN

 

[Sleufoot]

this is what ET is referring to. Not sure if you year is the same. I made the mistake of cleaning and lubricating the same on my 44' B and now the throttle is loose and will not stay at the desired speed. Guess i need to clean of lube and let is rust again! Maybe your spring is weak or broken.

I had that same problem with my 40B. I asked a gentleman that knows just about everything John Deere. He said to pick up some dirt and put it at the pivot point. Did that and sure enough that worked. Tom in Mn.

 

[GregoryU]

Finally found it A49deere! I had googled the adjustment before but hadn't used that exact wordage. That's probably the best explanation yet. Thank you everyone!

 

[GregoryU]

Just an update. Everything seems to be set right (as near as I can tell) so maybe it's in my throttle friction. Not going to mess with it now because my steering pedestal was broken at one time and I want to get a new one. The throttle handle was broken also so I want to replace that too. Altho everything works, I'd like to get rid of that bird droppings looking welding on the cast iron!