Could you post a picture of the 4 bolts holding the gear box? Also the push bolt on the pulley side is broken and I can’t turn the threaded piece that’s still there. Any suggestions?
Flail Mower Any Ford 918H owners?
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the old grind
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Time to apply the blue wrench? Looks like the OEM bolt froze and snapped off when trying to get it freed up. I've had 'em budge after cooling when they didn't seem to while still hot, roasted 'em good either way. Gear box bolts look to be accessed from the bottom. btw, nice pics, guys. 
John0829
Veteran Member
Penetrating oil and a small hammer will work on the bolt. Spray it and let it soak for awhile then start tapping it with the hammer while gently trying to turn it with vise grips or small pipe wrench. Keep soaking and tapping until it begins to move, it will take time so don't expect it to happen in the 5 minutes. Once it starts to move keep spraying and rocking it back and forth until you get it out.
I would use heat as a last resort.
The bolts for the gearbox are right under it.
I would use heat as a last resort.
The bolts for the gearbox are right under it.
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Thanks a million. You’ve been extremely helpful!! Just hope those gear box bolts aren’t frozen
will let you know when I can get around to trying them. By the way why do you say use heat as a last resort?
the old grind
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I mentioned heat, but only on the adjustment bolt/tab & not on the gearbox bolts. Sorry for any confusion. Kroil, Free All, Gibbs, Liquid Wrench NOT std WD-40 to loosen rust can be easier to use but 50/50 ATF & acetone still rules. All might need time to soak and reapplications can be every few hours.
tip: if you use 50/50 apply pure acetone every other time or so. (chip brush etc not poly) ATF will remain after the solvent evaporates out. The ratio once applied will favor ATF and lose its wicking ability to full depth, as in more acetone should suck into the oil vs be diluted/shared from more 50/50 mix. As I use up a small batch for a farm or machine job, say 2-4 oz (tall glass olive jar < 1/2 way, tiny drinking water bottle <1/2 way, etc) I just add a bit more acetone as I use it up.
btw: PO seems to have tried Vise-Grips on the broken adjuster bolt and failed. Bet it wasn't hot, can't tell if he knew not to loosen rusty chit 'dry'. I'd soak for a day or two if I had time (all bolts mentioned from all sides), maybe heat the adjuster if I didn't. Also, and from experience I wouldn't expect to have to loosen the gearbox bolts to change a belt set.
So say you let the bearing shield loose for now and see if you don't have easily and workably 1" - 1 1/2" of 'wiggle room' with mere hand pressure as I did. We need maybe 1/2-3/4" of it to get a belt off. And yeah, we do put 'em on one 'position' at a time and walk 'em over one groove to the next. (You knew that) Tell us when you get to the hard part.
tip: if you use 50/50 apply pure acetone every other time or so. (chip brush etc not poly) ATF will remain after the solvent evaporates out. The ratio once applied will favor ATF and lose its wicking ability to full depth, as in more acetone should suck into the oil vs be diluted/shared from more 50/50 mix. As I use up a small batch for a farm or machine job, say 2-4 oz (tall glass olive jar < 1/2 way, tiny drinking water bottle <1/2 way, etc) I just add a bit more acetone as I use it up.
btw: PO seems to have tried Vise-Grips on the broken adjuster bolt and failed. Bet it wasn't hot, can't tell if he knew not to loosen rusty chit 'dry'. I'd soak for a day or two if I had time (all bolts mentioned from all sides), maybe heat the adjuster if I didn't. Also, and from experience I wouldn't expect to have to loosen the gearbox bolts to change a belt set.
So say you let the bearing shield loose for now and see if you don't have easily and workably 1" - 1 1/2" of 'wiggle room' with mere hand pressure as I did. We need maybe 1/2-3/4" of it to get a belt off. And yeah, we do put 'em on one 'position' at a time and walk 'em over one groove to the next. (You knew that) Tell us when you get to the hard part.
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John0829
Veteran Member
As said soak it and tap it with a hammer the vibrations will help to get the oil to penetrate along the threads. I have removed many frozen bolts and pins by doing this. It is slow and can take days, I prefer to leave heat until the ultimate last thing when working around bearings and seals. I have seen to many people use a little heat, then a little bit more and a little bit more, then end up replacing seals that start leaking from being cooked.
So I’ve been soaking that bolt for a couple days. Really not making any progress. I did flatten it with a Dremel on both sides to try to turn it. But I just started twisting the bolt. Any reason not to just forget the lubricant and just try to drill it out. What’s the negative of that.
John0829
Veteran Member
No negative at all, drill away, if you can get straight on and centered to it. Sometimes if you can find a left hand drill bit as you are drill they will come lose and back out. Finding left hand drill bits is the hard part.
the old grind
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If you drill just saw off all but 2-3 threads and square it up with a file. Center-punch and use a #3-4 center drill or 1/8" stub drill to pilot the hole good & on center. Follow with a bit one size (1/16") smaller than the bolt/thread size. I have pic of one I did where the thread came out looking like 4-5 coils of a spring. It had been soaked in Kroil 2x/day for > a week & had to be drilled out anyway.
btw, when working under cars at Midas in the '70s I learned to just buff a broken exhaust stud flush to the manifold then drill & tap offset 1/8" or so leaving the old piece in a crescent shape as if part of the native metal. D&T was with airgun as I would use years later putting heli-coils in pan rails (not often) in a GM transmission plant. Again you don't really need to preserve the thread in the tab. If you're not comfortable with jam-nuts (double?) on both sides of it, opening the hole up and tapping for the next larger size bolt wouldn't take much. You want to be confident that the adjustment won't vibrate loose.
btw, when working under cars at Midas in the '70s I learned to just buff a broken exhaust stud flush to the manifold then drill & tap offset 1/8" or so leaving the old piece in a crescent shape as if part of the native metal. D&T was with airgun as I would use years later putting heli-coils in pan rails (not often) in a GM transmission plant. Again you don't really need to preserve the thread in the tab. If you're not comfortable with jam-nuts (double?) on both sides of it, opening the hole up and tapping for the next larger size bolt wouldn't take much. You want to be confident that the adjustment won't vibrate loose.
dieselscout80
Veteran Member
If you drill it use a lefthand drill bit and it may loosen the stuck bolt.