Governor Adjustment Locations on 1955 Lo Boy

[EdinCincinnati]

This picture is of the governor on my 1955 Lo Boy...can someone tell me what is adjusted by the items labeled 1 & 2 in the picture?

I am having throttle issues...I've read 15 other threads here about checking linkage, free movement of components, carburetor ease of movement and through elimination I am down to the problem either being the spring needing replacement or the governor not adjusted properly but I don't know what adjustment points labeled 1 & 2 in the attached picture do.

Additionally, I assume these are the only locations to adjust the governor...if there are/is another place to adjust the governor, please advise and explain.

Thanks-

EdinCincinnati

[Waif]

With throttle being the issue , once all linkage is confirmed free but secure in it' s travel I would look at adjustment at/ near carb.
Similar to a carb install. Where governor affects carb ,yours may be adjustable and something is out of adjustment.
On my older tractor a loose screw at throttle to governor linkage behind carb allowed governor linkage to move and affected operator seat control of throttle.

That does not answer your fittings shown purposes .

[Jim Becker]

What EXACTLY is your throttle issue?

Number 1 adjusts maximum engine speed. It does so by setting maximum movement of the control linkage and thus limit tension on the governor spring. Turning it in slows the maximum, turning it out increases the maximum.

Number 2 adjusts a bumper spring. The purpose is to keep the governor from overreacting and causing the engine speed to cycle up and down. The adjustment needs to be turned in enough to stop the surges but no more than the minimum needed.

If you have some other problem, neither of these screws will fix it.

[EdinCincinnati]

The problem is when pushing the throttle setting lever to increase RPMs, the engine speed does not increase as if something in the linkage is stuck. I have to rapidly move the throttle lever forward and back until whatever the problem is "becomes unstuck or releases" and the engine RPM increases. But when I do get the engine RPMs faster and release clutch to start movement, the rpms slowly decrease to what I think is around 25% of WO throttle and then it stops there even though the throttle setting lever is still at maximum RPM setting. Additionally, when the engine comes under additional strain, such as going up an incline/hill, the RPMs slow down to almost idle and only when the hill top is reached do the RPMs start to increase back towards W.O.T.

I have twice set the linkage from the carburetor to the rocker arm.
I have lubricated all points of movement and everything seems lubricated well.
I have disconnected the long throttle rod at the governor lever connection and there is easy free movement from that point to the carburetor almost to the point of being sloppy (tractor not running).
I had the tractor repainted and the governor spring was painted. I thought this might be the issue but it can easily be pulled separating the coils. Additionally with the spring at idle setting it is loose, no resistance at all. It doesn't make resistive contact until the throttle gets to 1/3 of wide open throttle. Which makes me also wonder if the spring is too long.

I did change the carburetor from a zenith to an original IH but this symptom was happening with the zenith too.

I have also checked the long throttle rod for rubbing across the touch control / hydraulic component under the hood and where it passes the engine block and it moves freely.

[John *.?-!.* cub owner]

My thoughts are that either the holes for the spring that connects from the upper lever to the cross shaft (behind 1 in your photo) are worn, or more likely where the cross shaft (across front of tractor) enters the bracket the spring I mentioned has worn. It is a slip fit with a small Wooruff key, and they can become badly worn over time. I have repaired extremely worn ones with a small bushing made from an aluminum soda can, using Loctite, and some have used JB Weld. It only takes a very small amount of play at that point to create a lot of slop in engien responce.

[EdinCincinnati]

Okay...this is the underside of adjustment #1 in my first post...now I see how it limits the amount of movement of the governor arm

This is my throttle rod (disconnected from the governor) in lowest setting and it extends past the lever when the carburetor is at its stop

Does this mean the rod needs to be shortened to get more useful notches in the throttle setting plate?


This is the governor spring and the coils top and bottom are touch the arm above and below from moving towards each other any further.

Is this normal or is the spring to long? Looking at the picture of a new spring at TMTractor...it seems to have one less coil than the one on my tractor:

[Glen]

Hi,
I see something in your pics that needs changing. The fast idle speed adjustment, number 1 in your 1st pic above, is turned in too far. It looks like the original bolt and lock nut in the pics.
Loosen the lock nut, which is below the bolt head, and back out the bolt. I measured on my Cub the distance of the bolt showing, between the bottom of the bolt head, and the top of the lock nut, it is 5/16 inch. Which is about like in the pic from TM Tractor below.
Yours is much less than that in the pics.
Setting the bolt there should give you an approximately close to right high idle speed.
You could measure it with a measure, if you have one that will fit in where the bolt is.
I would connect an automotive test tachometer to the coil, and check the top speed. It should be 1800 RPM. Set the bolt so the throttle won't go higher than that.
Be careful to not over speed the engine, if something has been changed that this setting doesn't work like it originally should.
After setting that, see how the throttle and governor work, and if there is still something else wrong.

[John *.?-!.* cub owner]

Looking at this picture I see a dark area where the shaft goes into the larger fitting and what appears to be space on either side of the Woodruf key. If there is any play there it will cause problems

[Glen]

Hi,
To check what John said above, with the engine off, and the throttle above idle speed some, reach in and hold the piece still that the shaft goes into, and then see if the shaft turns in the hole. It should have no play there. They sometimes wear over the years and get loose.

Number 2 in your pic might need adjusting. After setting the number 1, if it doesn't work right at slower speeds, turn number 2 out slowly, trying it as you adjust it. Shut off the engine when you adjust it, it is close to the fan.
It says in the manual don't turn it in too far, it can interfere with the slow idle speed.
Don't turn it out too far either, it will fall out. Looks like maybe 3 turns maximum you can adjust it out from where it is in your pics, my opinion. If adjusting it doesn't improve anything, set it like it was probably.
The engine should run smoothly, and have good response from the governor.
They don't use all the notches on the throttle. Usually about 2 at each end that the lever does not use.

[Jim Becker]

Looking at the same picture John referenced, I see space between the coils of the spring. Unless it is under tension, the coils should be tight together. Spring is probably stretched.

[EdinCincinnati]

Thanks Everyone for your responses this far...I'll investigate starting Tuesday and report back!

[staninlowerAL]

This is my throttle rod (disconnected from the governor) in lowest setting and it extends past the lever when the carburetor is at its stop
Pic 3.jpg
Does this mean the rod needs to be shortened to get more useful notches in the throttle setting plate?

When the engine is not running, does this throttle lever (not the rod) move freely through its full range of travel without any restriction? If not it needs to be freed up. Might even need to be removed and clean the paint and buildup on the shaft where it pivots. It's cast so don't get too agressive with removal or it might break. Good Luck Stan

[Glen]

Hi,
You could also set the low idle speed if you have a tachometer connected to the engine, it should be 475 RPM, or down to 450, or up to 500, the Cub service manual says.
The screw for setting the low speed is behind the upper part of the carb, between the carb and the engine, the screw faces forward.
You said you put on an IH carburetor. There is info in the Cub owner's manual for setting the idle mixture screw on top of the carb. It should be set when the engine is warm. The ones I have set usually need to be open about 1 1/2 turns to run good.

http://www.farmallcub.info/manuals/gss- ... 001-04.jpg

http://farmallcub.com/rudi_cub/www.clea ... age-22.jpg

[EdinCincinnati]

Thanks again for all the responses...I tinkered with it tonight. I disconnected the governor spring and the throttle rod and governor arm move freely. There is some binding in the rocker arm but when I reattach the governor spring the binding is even more prevalent.

Thoughts?

I have ordered a tach...it'll be here Wednesday or Thursday. I don't want to go to much further until I know how fast the engine is turning.

[Glen]

Hi,
It sounds like you need to use penetrating oil on the base of the arm that the throttle rod hooks onto, where it pivots, and work it by hand, and free it up. It is a common thing on Cubs that the arm gets tight there.
Here are pics of it, use penetrating oil at both ends. In the 1st pic, the shaft is solid on the governor, and the arm turns, lube it there where the cotter key is.
After it loosens up, oil it, and the other throttle linkage with motor oil.