Can we get more power from a Cub?

[Jackman]

Wow I like these post they are helpful, I think Paul may be have hit the nail on the head as I had just come in from mowing and it picked up some power after I had unthreaded the swivel end of the govner rod about 5 turns I imediately noticed the RPM's picked up and it powered thru the thick grass much better than before the adjustment..... Now the new and more important question is, how do I properly adjust the governer? Thanks all for the help

[Jim Becker]

Engine off, unpin the linkage, push the governor control forward, hold the carburetor throttle wide open. Adjust the linkage to the longest length that will allow the pin to go back in without any of the other parts moving.

[evielboweviel]

my experience was to switch to synthetic oil in the tractor and use Mobil one synthetic grease in the mower. Grease the mower heavy to force the old grease out. Also my 76 is tired and needs to mow some before it gets to max power. Defintly keep the blades sharp, the front of the deck lower than the back, I ran about a half inch difference mowing at 3 inches. Last change and only if desperate is to down size the PTO pulley, this lets you still cut in 1st gear and get a good cut without taking as much power. Didnot do this on the 76 however did this on a early cub when running the 59 on it. This early cub liked the 42 in heavy orchard grass real well.
Ron

['Country' Elliott]

Hey Jack...That dealer's giving you a line of BULL ! I have a Zenith carb on my "Carol Elizabeth" Cub and it doesn't add an ounce of horse power ! It DOES make any Cub run smoother (especially at idle, than the old IH carbs).

Short of breaking down your engine...overboring it and adding dombed aluminum pistons and a supercharger (just kiddin') I think you'll just have to mow: 1) Closer 2) When it's dryer 3) With the blades sharper 4) With the deck tipped forward 5) With the governor adjusted properly. AND...MOST OF ALL...LEAN FORWARD INTO THOSE TURNS (for LESS wind resistance)!!!

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

Jack, I have a Zentigh for sale on Ebay, but if your old carb is good, I doubt it will increase your horsepower enough to notice, if any. To get more out of a bigger carb yu would have to follow Countries instructions, newer manifold, camshaft, domed pistons, different head (or modifiying existing one), adjsuting rpm higher, etc. That I believe was how they did it on models such as 154, 184.

[Jackman]

It was a long day spent tinkering with the Cub and I believe its running at its best had a full tune up and thanks to Jim Becker I even did a proper adjustment to the govnor yet it still can't handel the L59 oh well I still love this old tractor maybe some day Ill have to do the dome top pistons with a supercharger thing Thanks all Jack

[countershaft]

the Cub is "under powered" for the 59 mower and no matter what you do, it ain't gonna help. The International version of the Cub has more hp and rpm's and does a better job of mowing. I've used one for 10 years and know. You have to cut twice, if it's high , run in 1st gear, don't take a full 59" cut , keep the blades sharp, keep it lubed and cut when it's dry. It's just a full load for the little Cub. I also use a Super A and what a world of difference. It's all in the hp and rpm's.

[Dale51]

Gent I work with has a 61 cub with 59 mower & he uses it for a brush hog. He does not have low power problem.
I ask him about it. Here is what he told me.
He used to have the same problem you are having .
1. check for 1800 rpms with no load. (you adjusted gov. link but that does not mean it right.)
2. Check for full compression on each cyl. not sure what it should be but at least 100 to 110lb per. (this was his problem full rebuild fixed it.)
3. ck air cleaner for service.
He runs a motor cycle foam clamp on air cleaner when he uses it for a brush hog.(tells me you can't believe the diff. in HP.)
He suggested you disconnect the air cleaner & try it for a short time but not to long as dirt will get in the carb . just a test trial.
4. Are you belts to tight as this will rob you of more HP than you think.
5. last he said make sure the blades are on right his deck was new & came with blades on back wards.

I have no experience with the above just going on what he said.
I do know that #3 above will make a small diff. As a oil bath air cleaner starves carb of air.(takes a lot of vac to get air tru.)

[Patbretagne]

Just a thought, but is the governor and linkage from carb to governor all set correctly so you are getting all the power the tractor is suppose to produce? If the governor connecting rod (connected to the carb) is not adjusted correctly, it will not open the throttle all the way.

That's my bet, when our number two came home it ran well but a litlle reluctant on hills, I experimented a piece of string tied on the carb throttle linkage direct thereby not using the govenor, and wow nearly landed on the moon , Have since adjusted as PaulB suggests (there is a recent thread on this subject) and we now have a "controlled" takeoff what a difference
Pat
Best of luck

[Donny M]

Countershaft wrote:

the Cub is "under powered" for the 59 mower and no matter what you do, it ain't gonna help.

I respectfully have to disagree. This set up mows quite well up hill or wet.




I do have the front of the mower lower than the rear by an inch or so. I mow in second gear and could mow in third if I could hold on well enough. For very tall grass (18"+) I make two passes.

[George Willer]

Thanks all, At present I am running on Sunoco 93 octane gas and have seen no differance in performance over the low octane gas next I will try the lead substatute, it could only help however I don't see a performance gain but will try just the same. The deck has just had a good going over and is well maintained but the deck pitch is something that I have not even thought of , so that is something I will also try.. Back when I bought the L59 the dealer had mentioned that there is a bigger carb called a Zenith that is supposed to give the engine a boost, I have had no luck getting any other info on that carb..... Has anyone here heard of the Zenith carb? Thanks Jack

Jack,

Opinions vary, but I know of absolutely no reason that the Zenith carburetor will improve power over that of an engine with the IH carburetor in equal condition. Fact is that the idling will be poorer due to the slightly lower air velocity and therefore poorer atomization.

The same gain from changing to Zenith will be realized by a good overhaul of the IH carb.

The dearler you talked to was blowing smoke to sell a carburetor!

[Jackman]

Some good post here I do appreciate.... The mower blades spin by hand with easy when the pto is disengauged so I am sure the Cub is the issue and not the L59. My carb seems to be in good shape I diassembled it set the float I was not sure if I did the right thing with main metering jet, does it thread in any old way or is there a certain position it goes in? I also need to check the full throttle rpm's maybe I am not getting 1800 revs. I also think its time to do a compression check after 50 years of use maybe this Cub is just plain worn. Anyone know what the compression should be? Thanks all Jack

[WKPoor]

Jackman, When an Engine looses power and its not tuning related, I would rather see you do a leak test. Actuall compression doesn't change. An engine with leaks however will loose power. Remove all the plugs and put a supply of compressed air on each cylinder one at a time on top dead center and listen for a leak. It won't be perfectly tight even if its good, but you'll know if it sounds excessive. This method will determine actuall engine health much more accuratley than a cranking compression check. Cranking rpm's may hide a problem. If you use that method of cranking make sure each cylinder gets the same number of revs. A leaky engine could still pump up your tester if you crank long enough.

[Dale51]

Jackman, When an Engine looses power and its not tuning related, I would rather see you do a leak test. Actual compression doesn't change. An engine with leaks however will loose power. Remove all the plugs and put a supply of compressed air on each cylinder one at a time on top dead center and listen for a leak. It won't be perfectly tight even if its good, but you'll know if it sounds excessive. This method will determine actual engine health much more accurately than a cranking compression check. Cranking rpm's may hide a problem. If you use that method of cranking make sure each cylinder gets the same number of revs. A leaky engine could still pump up your tester if you crank long enough.

WKPoor,
Come on big guy a air leak test to see if it needs rebuilt with out having done one would confuse most people beyond belief & with out the right
tools is almost useless. What you suggest is used mostly to find blowed
head gaskets.
A simple compression test to start will tell you if there is need for further testing or work to be done.

[Dale51]

Some good post here I do appreciate.... The mower blades spin by hand with easy when the pto is disengauged so I am sure the Cub is the issue and not the L59. My carb seems to be in good shape I diassembled it set the float I was not sure if I did the right thing with main metering jet, does it thread in any old way or is there a certain position it goes in? I also need to check the full throttle rpm's maybe I am not getting 1800 revs. I also think its time to do a compression check after 50 years of use maybe this Cub is just plain worn. Anyone know what the compression should be? Thanks all Jack

This should help you

http://www.cleancomputes.com/Cub/Blue%2 ... e%2006.jpg