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Discussion Starter #1
Noticed the thread on removing the L starter clutch (hub/sprocket) to replace rear crank seal & how it got detoured into repairing the clutch 'cam rollers'.

Getting the hub off the rear of the crank shaft can be a bear. I've succeded by striking the end of a wrench on the flats w/sharp hammer blows. Tough ones require some soak time w/your fav penetrating oil on internal threads, remove bolt 1st, if there is one. For the most stubborn; an old trick is to stuff cord into cylinder by removing spark plug & backing piston well down. The idea is to feed enough cord (venetian blind cord size) in thru plug hole, so as to partially fill the cylinder, so that you can rotate the crank compressing the cord & blocking the piston, giving you something to fight against when you try to free the starter clutch hub.

I've also found that balky starter clutches, that have worn, insufficiently lubed, cam rollers can often be salvaged w/o buying new cam rollers. Many times these pesky cam rollers have merely succumbed to 'pattern wear'. Usually the inner surfaces, that contact the spinning hub whenever the motor is running, develop a flat spot. This is easily seen as a highly polished line & ever so slight groove. Its surprisingly easy to sand/grind away the trouble spots by hand. I've used fine (220 grit or finer) went/dry carborundum paper laid on my table saw's flat iron surface. Simply polish away the concave groove & try to reform a nicely rounded surface on the individual cam rollers.
 

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Just Have a Little Faith!
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I knew a guy with a Chevy who tried the cotton cord trick to change a valve spring. It cut off a piece of the cord. When he started the car, it blew black cotton fuzz out the exhaust.
 

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Discussion Starter #4
Basic info like this is in readily available from free online GRAVELY manuals. The '74 vintage 7.6 Shop Manual has this "Note: All threads are right hand." under Starter Clutch Removal.

Just to be sure, is the starter clutch a right hand thread?
Thought I might save folks from pulling the head to jam piston by inserting a block of wood in cylinder, as this Shop Manual instructs. I've been lucky time & time again just "by striking the end of a wrench on the flats w/sharp hammer blows" but it does take a quick arm.
 

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A friend tells the story of using the rope trick on a recalcitrant aircraft engine. Had a valve that had gotten crudded up and wasn't seating well, bad compression. Standard two-valve OHV arrangement, so he stuffed rope in there, pulled on the prop to lock the valves in place, undid the valve spring. Backed off the prop, got the rope out, let the valve drop into the cylinder enough to put grinding goop on it, chucked the butt of the stem in and electric drill, and proceeded to lap the valve without having taken the top end apart. Rope back in, valve spring back on, fired it up, and flew it home.

There are some pretty cool tricks lurking out there :)
 

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Noticed the thread on removing the L starter clutch (hub/sprocket) to replace rear crank seal & how it got detoured into repairing the clutch 'cam rollers'.

Getting the hub off the rear of the crank shaft can be a bear. I've succeded by striking the end of a wrench on the flats w/sharp hammer blows. Tough ones require some soak time w/your fav penetrating oil on internal threads, remove bolt 1st, if there is one. For the most stubborn; an old trick is to stuff cord into cylinder by removing spark plug & backing piston well down. The idea is to feed enough cord (venetian blind cord size) in thru plug hole, so as to partially fill the cylinder, so that you can rotate the crank compressing the cord & blocking the piston, giving you something to fight against when you try to free the starter clutch hub.

I've also found that balky starter clutches, that have worn, insufficiently lubed, cam rollers can often be salvaged w/o buying new cam rollers. Many times these pesky cam rollers have merely succumbed to 'pattern wear'. Usually the inner surfaces, that contact the spinning hub whenever the motor is running, develop a flat spot. This is easily seen as a highly polished line & ever so slight groove. Its surprisingly easy to sand/grind away the trouble spots by hand. I've used fine (220 grit or finer) went/dry carborundum paper laid on my table saw's flat iron surface. Simply polish away the concave groove & try to reform a nicely rounded surface on the individual cam rollers.

I'll have to give that a try with some of the spare/used cam rollers that I have. I was under the impression that once they were rounded off, they were no longer usable.
 

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Discussion Starter #7
IMO you have a false "impression".

I was under the impression that once they were rounded off, they were no longer usable.
The cam rollers are "rounded off" when they're new & rely on their "rounded" surface in order to roll & function as cams. Long service & lack of lube conspire to wear flat defects in the "rounded" surface that resist the rolling action. Please by all means "try" it. If your roller cams suffer the typical pattern wear I described you'll like it. You will not believe how easy it is to salvage these little buggers.
 

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A friend tells the story of using the rope trick on a recalcitrant aircraft engine. Had a valve that had gotten crudded up and wasn't seating well, bad compression. Standard two-valve OHV arrangement, so he stuffed rope in there, pulled on the prop to lock the valves in place, undid the valve spring. Backed off the prop, got the rope out, let the valve drop into the cylinder enough to put grinding goop on it, chucked the butt of the stem in and electric drill, and proceeded to lap the valve without having taken the top end apart. Rope back in, valve spring back on, fired it up, and flew it home.

There are some pretty cool tricks lurking out there :)
so he never was able to wash the grinding compound off? Wonder how long that cylinder kept compression? That unwashed grit will raise havoc with a cylinder.
 

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8N's & Gravelys
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Old3Banger - thanks for sharing your technique on recovering the cams. I honed out the flat spots, and took a badly slipping clutch to like-new performance.
 

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It was unfortunate as he did seem knowledgeable but dang when one almost kills any "free" conversation in an entire forum and turns almost every thread into battlefield even if they are right,, well the inevitable was just a matter of time, as I said unfortunate he would have been a great asset.
 

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It was the quotations that did it for me. I don't even think he realized what he was doing. He just couldn't help sounding like an ***. Oh well, I really wanted to see pics of his Gravely monster. Probably something like one with extension axles and bigger tires. Anyone else ever do something similar?
 

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I thought the "monster" would have been neat to see, there aren't many Gravelys in my area and I have never seen a Gravely rider up close to have a real clear reference, so the pics would have been nice. I just assume it would look very similar to a walkbehind but have bigger tires and a wider stance. If I remember the thread (and I may not) there was a mention of to fast of ground speed for the machine to be useful? Didn't the riders have a slow speed or did I misunderstand something? I also assume since it had larger tires any implements wouldn't have worked on it without modifications? Pics would have been nice.
 

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I thought the "monster" would have been neat to see, there aren't many Gravelys in my area and I have never seen a Gravely rider up close to have a real clear reference, so the pics would have been nice. I just assume it would look very similar to a walkbehind but have bigger tires and a wider stance. If I remember the thread (and I may not) there was a mention of to fast of ground speed for the machine to be useful? Didn't the riders have a slow speed or did I misunderstand something? I also assume since it had larger tires any implements wouldn't have worked on it without modifications? Pics would have been nice.
if memory serves me correctly it had 12 inch tires. GRW's are 12 inch, so implements would work fine. I can ask him if anyone cares.
 

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Collector of many tractors
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I thought the "monster" would have been neat to see, there aren't many Gravelys in my area and I have never seen a Gravely rider up close to have a real clear reference, so the pics would have been nice. I just assume it would look very similar to a walkbehind but have bigger tires and a wider stance. If I remember the thread (and I may not) there was a mention of to fast of ground speed for the machine to be useful? Didn't the riders have a slow speed or did I misunderstand something? I also assume since it had larger tires any implements wouldn't have worked on it without modifications? Pics would have been nice.

In Pa and never seen a Gravely ridder ???

I think Pa the place to be to see one...
 

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Im not kiddin, I've never seen one up close in person, just the pics you guys post ,,,,, I must be "sheltered" and need to get out more.
 

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Old3Banger,

Thanks a million, your tip on restoring worn out clutch cams worked like a charm & saved me cash & time. Just got 2 old Gravely walk behind tractors, the starter clutch on 1 was toast & I choked on the obscene price of new cams. Your post was a terrific introduction to this Gravely forum.

Got any tips on restoring balky remote PTO lever/rods?
 
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