Throttle

[Regarrr]

Does anyone have information, or know where I can find information on "tuning" the throttle? I think the Cub that I have is early 60's but there was know data plate to know for sure.

Anyway, here's a little background. When I got the tractor, it ran pretty decent, but the throttle lever did nothing except bend the linkage. So I was basically stuck at one throttle setting. Under load, sometimes the engine would rev up and plow through and sometimes it would peter out. I thought the reason was the governor. So I took off the governor housing and found the bellcrank from the throttle lever linkage to the spring was seized. I took that apart and cleaned it and it now moves easily. So now the throttle lever actually moves the linkage, but now the tractor is running very poorly. I've messed with the adjustable fork end link on the right side front that leads from the governor to the carburetor, the screw on the back side of the carburetor, and the set screw in the governor housing, but I really don't know how they should be set up. Guessing and trial and error aren't getting me very far.

If anyone has a link to information or knows how to get a base setting that I could tweak, that would be greatly appreciated.

[Eugene]

Check your ignition timing.

[Regarrr]

Is there anything related to the fuel system that I should look into before checking the ignition timing? I can pretty much guarantee that anything related to fuel or throttle is out of adjustment. I just don't know where to start when it comes to adjusting them.

[Eugene]

Check your ignition timing.

You removed the governor.

Check your ignition timing.

[Regarrr]

I'm sorry, I think I was unclear, I only removed the cover, I didn't remove the actual governor.

[Scrivet]

I don't know where to start on this but please stop "trying things" until you know what they do. You have probably created a lot more work and trouble for yourself. In the heading above is "Rudi's Manuals" later on spend some time poking around there. For now lets just get you to the Fuel System Blue Ribbon Service Manual and have you spend a little time reading. There's a carb section and governor section that will give you some insight. http://www.cleancomputes.com/Cub/Blue%20Ribbon%20Service%20Manuals/GSS-1132%20Fuel%20System/GSS-1132%20Fuel%20System.htm

[Barnyard]

Okay, I agree with Eugene and Scrivet, at this point you need to stop messing and guessing.

I've messed with the adjustable fork end link on the right side front that leads from the governor to the carburetor,

Read this for starters and then we can go to the next step. Start at the third paragraph.

carb-adj.JPG (79.18 KiB) Viewed 658 times

[randallc]

Welcome to the forum from Arkansas. This site is loaded with a ton of information. There are Service Manuals, there are threads discussing just about everything, there are how to sections. And for a new guy it may be a whole lot of information, but start digging in one piece at a time, get the answer to it, move on to the next. Then there are folks who can help with the answer. So kick back in front of the computer and enjoy the information on this great site.

[Matt Kirsch]

You need to "time" the governor to the carburetor throttle now that you've changed the link on that side. It's pretty simple:

0. Tractor OFF.
1. Disconnect the linkage running to the carburetor from the governor end by removing the pin from the yoke.
2. Set the throttle lever at the seat to FULL. This should force the arm that connects to the carburetor linkage all the way forward.
3. Adjust the length of the carburetor linkage so the pin just slides through the yoke when you are pulling the carburetor throttle to wide open.

[PoconoCub]

You need to "time" the governor to the carburetor throttle now that you've changed the link on that side. It's pretty simple:

0. Tractor OFF.
1. Disconnect the linkage running to the carburetor from the governor end by removing the pin from the yoke.
2. Set the throttle lever at the seat to FULL. This should force the arm that connects to the carburetor linkage all the way forward.
3. Adjust the length of the carburetor linkage so the pin just slides through the yoke when you are pulling the carburetor throttle to wide open.

I just want to make sure I did this right, it sure helped so far and I hope it works for Regarrr:

I set the throttle to full



Then I disconnected the carb rod from the governor lever



Then after turning the yoke 10 full turns I ended up with this



I do notice that the engine surges now, it seems to calm down after a bit. I can tell you I can climb up my driveway in 2nd gear without it bogging down like it used to forcing me to drop down to 1st gear.

Scott

[Radec Aksarben]

You need to "time" the governor to the carburetor throttle now that you've changed the link on that side. It's pretty simple:

0. Tractor OFF.
1. Disconnect the linkage running to the carburetor from the governor end by removing the pin from the yoke.
2. Set the throttle lever at the seat to FULL. This should force the arm that connects to the carburetor linkage all the way forward.
3. Adjust the length of the carburetor linkage so the pin just slides through the yoke when you are pulling the carburetor throttle to wide open.

I just want to make sure I did this right, it sure helped so for and I hope it works for Regarrr:

I set the throttle to full



Then I disconnected the carb rod from the governor lever



Then after turning the yoke 10 full turns I ended up with this



I do notice that the engine surges now, it seems to calm down after a bit. I can tell you I can climb up my driveway in 2nd gear without it bogging down like it used to forcing me to drop down to 1st gear.

Scott

If you read the governor section of the blue ribbon manual posted above by scrivet, it talks about how to solve the surging problem. It might be as simple as adjusting the low idle bumper.

[PoconoCub]

WOW.... with the adjustments that I made to the governor today I was able to back up my 300 foot uphill driveway with the throttle at just past 1/2 way. In the 12 years that I have owned the 57 I have never been able to do that, I was only able to make it part way up before it bogged down before.



Now I will have to ask mama for some money to do a tune up on her since it has been 12 years since the last one

Scott

[BIGHOSS]

If you are going to do a major tuneup such as points, plugs, dist cap, rotor, etc. and you have a distributor not a mag, I would encourgage you to consider switching to a Petronix electronic ignition. You will be amazed at the increase in performance. JMHO.

[PoconoCub]

If you are going to do a major tuneup such as points, plugs, dist cap, rotor, etc. and you have a distributor not a mag, I would encourgage you to consider switching to a Petronix electronic ignition. You will be amazed at the increase in performance. JMHO.

I do have a mag on the 57, but was considering switching to a regular distributor and installing a Petronix, of course I would have to get permission from mama

Scott

[Scrivet]

.......Now I will have to ask mama for some money to do a tune up on her since it has been 12 years since the last one

Scott

Don't know about the pertronix, but if it's been 12 years since a tune up, dare I ask how long it's been since a valve clearance adjustment check? Another possible area to get a little improvement from.