Governor repair and rebuild

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Transcript Governor repair and rebuild

Governor repair and rebuild
The VanOostrum brothers rebuilt
Rudi’s governor at the 2004
NorthEast Cubfest.
Clean it with diesel. The cover
fits tight, tap it loose with a soft
hammer. This governor has had a
hard and wet life. Water has left
corrosion and just about every
moving part is worn, both inside
and outside the case.
Worn clevis and rod
When you
get the cover
off, put a
finger over
the top and
pry off the
snap ring.
Worn governor thrust bushing
Wear occurs
on the weights
where they
swing on the
pins. You can
bronze them
and redrill.
Drive the
retaining
pin out
Bumper spring to the left of the
fork in the top of the housing
Worn holes, weak spring
The spring is shot.
Clean everything up good. Start
with the shaft.
The weights
The carrier
Thrust ball bearing
Old and new base bushing
Start driving the old bushing out
Then use the
new bushing
to force the
old one out
the bottom.
Make sure
the hole in
the bushing
lines up with
the hole in
the carrier.
Install shaft into the carrier and
flip it over.
File any burrs off the weights.
Cleaned up and pins go back in.
Drive weights onto that rusty shaft
Line up those holes!!!
Aligning the holes, a new pin goes in
New bushing and thrust bearing
Liberal coating of grease, install
bearing and snap ring.
Remove forks to replace
rockshaft bushing and seal
Remove bumper spring
Clean shaft
Remove seal
Remove throttle lever from the shaft
Needle bearing replacement
Out with the old and in with the new
New seal flush with edge
New spring, bend to tighten at
rockshaft in order to reduce play
Line up lock pin with drain hole for oil
and tap into housing with hammer
Clean up the mount with a file and
you’re done
Parts invoice in 2004 Canadian
dollars
Another governor rebuild.
Excellent info salvaged from the forum.
•
I took the governor off the Cub this weekend so I could repair the spring leavers (I'll let you know how that goes). The
upper leaver was worn enough to look like two holes were drilled in it. Now that the unit is off I've new problems to
deal with (isn't that the way it always works?).
Parts that look good include the weights and pins, and although it has some minor pitting, the shaft seems fine. The
thrust ball bearing probably needs to be replaced. Some of the ball bearings are scored and both races show some
pitting. I think the thrust bearing is OK, but I may replace it anyway if it's not too expensive. The bushings also seem
fine.
So here's where I run out of answers.
1 - inside the casting was a broken gasket (?) that fit around the shaft somewhere (looked like a washer made out of
thin gasket material), but I don't see it listed in the exploded view. Any ideas?
2 - Endplay of the shaft should be 0.004 to 0.013 - but I have a bit over 1/32 of an inch! I can't see from the diagram
how to take that up. The governor base bushing has a roll pin in it. so I can't push the weight carrier further down the
shaft to make up the difference. How is this corrected? Any connection to the unexplained gasket?
3 - I'm pretty sure that the distributor gear seal was in backwards. I'm not entirely sure what the "lip" of the seal is.
The old seal has two ridges, one has a little larger diameter than the other. I'm thinking that the wide ridge is pointed
back toward the governor so that the bevel on the distributor drive end meets both ridges. Is this correct?
4 - what else should I be looking for while I'm this far into it?
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I can only help with the seal. It goes with the open side toward the engine. When you reinstall it pay attention to the
depth setting in the service manual. If you seat it to deep it will wear on the governoer and damage the seal. I just
want to reconfirm this so I won't be pulling the governor back off in a few weeks to correct the oil leak (l can be pretty
dense). The ignition drive oil seal is installed "lip forward". To me, that means that the high side of the seal material
(i.e., smallest I.D.) contacts the governor and the "open end", as John put it, (largest I.D.) faces the engine.
•Bronco,The manual Gss-1411 has all the info you need.Take the gov. off ,remember to see where you marks are on the gear.Put the unit
in a aluminum or Brass vise holding the gear, soak the bottom of with kroil or liquid wrench or wd-40.Heat the housing,lightly tap the
outer edges of housing.it should break free there should be a alighment pin on the bottom . Everything will slide out.weights and so
on.there a garlock seal thats available from case/IH,clean everything up and inspect.....installation is reverse of disassembly..There I
sound like a Chilton car manual ..Bronco See if you can get that GSS manual its pretty user friendly....
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•I finally got a new governor spring, so I took the governor off and did a thorough cleaning. There was alot of gunk build up, causing the
levers to be very difficult to move. So I totally disassembled the levers and cleaned them as well. After they were put back together, they
were moving like new. I reinstalled them with the new spring in place. Then I put the governor back in. Lining up those dots really is hard
to do, cause you cant see in there, and you have to spin it, so you cant really see where you are putting the gears. Anyway, I got it back in
and bolted the cover back on it. I wanted to start it, to make sure it was timed before I put the rockshaft together. So I tried to start it, and
it wouldn't fire. Must be timed wrong. Took it out again, and tired again. This time, I took the dist cap off to see where it was pointing,
and reinserted. I was sure I had it this time. Then I tried to start it, and it wouldn't start. All I could think is that I had it timed on exhaust
stroke, so I switched number 1 and number 4 plug wired, and she started right up. Then I switched 2 and 3. I will redo the governor
another time. Not sure how I got it backwards?
Then I was putting the rockshaft into the governor lever and the key fell to the ground. I said "oh
fffuuuuuuuudddddgggggggggeeeeee!!!!" Picture Ralphie from the Christmas Story when he dropped the lug nuts. I couldn't find it, so I
had to make a trip to Lowes for a new one. I quickly tried it when I got home, and now I see what a Governor is supposed to be like. I
havn't had a chance to try it under load yet, because it was getting dark, and the mosquitos were eating me. I'll probably get West Nile
now. Tomorrow, I will shim and loctite the rockshaft, and after some time for it to set up, try cutting some grass again. I have my fingers
crossed.
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•I will check and see if I still have the bill and part numbers. My IH dealer was able to cross reference all of the parts with the old parts
catalog numbers. The only one that gave him a little trouble was the weight pin. Apparently they no longer make weight pins for the older
Cubs - I want to say serial numbers lower than 19#,###. I don't recall the exact number, but perhaps you will know when IH changed
their design.
Beaconlight is the mastermind behind the roll pin idea, I just used a little common sense to impliment his idea. The roll pin was a
standard 1/4" pin available at any good hardware - 35 cents at my ACE hardware store. If I remember correctly, I used a 1/4" bit - I do
know that 7/32" is too small. You will want to drill the new hole using a drill press if you can. I think it would be tough (but perhaps not
impossible) to hand drill a straight hole. The existing hole is, of course, out of round due to wear and fairly close to the size of your drill
bit, so binding would be a concern if you hand drill - just my opinion.
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I was hesitant to let the pin collapse by driving it in. The castings are thin enough that I was afraid of cracking them,
so I collapsed the pin a bit in the vise before installing it. It still went in nice and tight and I added a little Loc-Tight
for insurance. Be sure to orient the pin such that the groove (point where the walls of the pin meet when collapsed) is
on the opposite side of where the governor spring will rest. Once through, I used a hacksaw to cut off the protruding
roll pin ends and filed them smooth with the casting. I then used a Dremel tool and small grinding stone to bevel the
roll pin edges slightly so they wouldn't cut into the spring. I think the roll pin is hardened and so I doubt that the
repaired leaver arms will ever need another repair, but if I do, it would be a simple matter to drive the worn pin out
and put a new one in.
Here is one part of the rebuild that I did have trouble with. Depending on the source consulted, governor drive gear
endplay should be around 0.020". I had 3 times that. The only way to make that up is by pressing the gear a bit further
down the shaft. My gear would not budge on the shaft. Now it looked like it came right out of the box after I cleaned
the oil off - no rust or corrosion and shiney bright, but hammer blows wouldn't budge it, and when I put it in a press it
started to mushroom the end of the shaft. I was afraid to ruin the assembly by bending the shaft or expanding the shaft
end so I re-installed it as it was. I did soak the assembly in PB blaster for a day or two, but I didn't know any other
tricks.
The rest of the rebuild is a "no-brainer" put the new parts in and you're done.
In your narrative it would be useful to explain how to pop the casting holding the drive gear and shaft out of the main
body casting. When you first see it, it looks to us novices like it's pressed in there for life.
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Couldn't you use thrust washers in the shaft to remove end play? Different thickness are available and you can install
on either on both ends. If not why not solid slug washers in the holes the shaft fits into. That works if they are not
through holes.
You have to adjust end play and gear lash like this in other machinery. Why not here? I never had a gov this far apart,
so this may not make sense in this application, but it works elsewhere.
•A thrust washer is any washer used to tke up end play if it fits over a shaft. Generally they go where there is a step in the diamater of the
shaft or where there is a gear, the end of an armature on an electric motor and the housing or bearing. A thrust washer limits )end to end)
lateral movement of a shaft. They can be used at either or both ends of a shaft to force the shaft the direction you want it and at the same
time limit movement. Usually you will use a number of real thim washers rather than 1 thick one. This lets you creep up on the
adjustment and distributes wear.
A slug washer is generally a solid (no cemter hole washer) that fits in the bore that the shaft turns in and limits travel end to end. This
does not work if the bore is a through hole.
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•When looking at Steve's pic. of the seal showing where it had apparently been rubbing the gear teeth it also appears that this seal had
been installed backwards. As we learned in an earlier post in the last week the side of the seal with the friction spring visible around the
perimeter of the rubber should go toward the oil supply/reservoir, or the governor in this case. Search this site for speedie sleeve info
http://www2.chicago-rawhide.com/faq/1.4.html
Page 7&8 of this site is a little governer info.
http://www.cleancomputes.com/Cub/I&T%20IH-50%20Shop%20Manuals/IH-50%20Complete/index.html
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•Here's the update on the '57 governor rebuild.
The spring leaver arms were worn badly as you will recall and each cost over $100 new from the IH dealer! Ouch, I couldn't afford that
so after some back and forth with several of you, I decided to drill the holes out to accept a 1/4" roll pin (thanks again to Beaconlight Bill
who had the roll pin epiphany). The pin is a perfect inside diameter once installed, but you will want to squash it a little in the vice before
pressing it into the drilled hole so it goes in snug but not so tight that it might break the casting (I put a little Loc-Tight on for good
measure. Cut the excess pin off level with the casting and it’s a perfect fix! I also beveled the edges a little to prevent the hardened pin
from cutting into the new spring.
Cost of 2 new spring leaver arms - $210 + shipping.
Cost of roll pin fix - $0.35.
Feeling you get knowing you have $209.65 left to spend on Cub parts – priceless.
While I was inside, I replaced all of the internal parts except the gear assembly and weights. Some of the bushings and bearings probably
didn’t need replacement, but while I was there… Surprisingly, everything else in the governor is relatively inexpensive, so the entire bill
including the ignition unit seal came to less than $90.
•
The throttle is now more responsive, and the governor is quick to pick up when the tractor is under load, and I’m enjoying the Cub more
than ever.
Thanks to everyone who helped me get through this repair.
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•Too much end play:
•If I remember correctly, the Blue Ribbon repair manual recommends 0.020 to 0.025" endplay between the governor drive gear and the
casting. The IT manual recommends 0.007 to 0.013 (again, if I remember it right). Endplay on my Cub was 0.063.
I tried to push the gear further down the shaft to make up endplay - it would not budge using more than a little "persuasion". Others on the
forum related similar problems, and one person heated the gear and still ruined a 20-ton shop press trying to do the job. My advice is, do
not attempt to eliminate endplay by moving the gear, unless you are fortunate enough to have an assembly that can be adjusted with
moderate pressure from press or hammer blows.
•
It was suggested that a thrust washer might be used to make up endplay. Yup, that works - and here's how I did it.
1 - punch out the rollpin that holds the weight carrier to the shaft. It comes out easy, just line up the holes in the casting and use a long
punch or round stock of the appropriate diameter to push the pin out the other side.
2 - put the assembly in the vice (or a similar wooden block setup) such that the casting rests on top of the jaws and the gear passes between
the jaws), i.e., shaft pointing up.
3 - put a piece of wood on the shaft end and tap shaft out of the casting and weight carrier (again, comes out easy). You now have three
separate pieces - the casting, weight carrier, and gear/shaft.
4 - with the gear/shaft and casting assembled, place the appropriate number of 5/8" ID/1" (minimum) OD shims or thrust washers over the
shaft. I couldn't find a thrust washer thinner than 0.065, so I used round, brass, 0.005" thick shims from McMaster and Carr (about $5 for 10
shims) . You can get them in other thicknesses and materials if you choose.
5 - tap or press the weight carrier back on the shaft (it will go on easily). Be sure the carrier is facing in the right direction and take care to
line up the weight carrier rollpin holes with the hole in the shaft.
6 - tap the rollpin through the carrier and shaft. The pin should go in easily. If not, the holes in the carrier and shaft are not properly aligned.
Reposition and try again. Be prepared to reposition a few times, do not try to force the rollpin through the hole. The pin is hardened and will
scar up the shaft.
I used all ten shims and reduced the endplay from 0.063 to 0.013 - the high spec limit according to the IT manual but a little less than
suggested by the BR repair manual - I thought this was an acceptable compromise.
Result: After the rebuild, governor picks up fast under load with speed change immediate and incremental along the entire sector range.