Flammable
New member
Hello there,
I am new to this site, and I hope this thread ended up in the right place.
I have recently purchased a 1975 ish Mighty-Mac 8B, it has an Onan 25 hp NHC-MS engine. It runs, and drives but has some irritating things happening. First thing is that when I turn the key, the engine cranks, and the skidder wants to start moving, so you try to correct it by moving the drive lever, but there doesn't seem to be a 'happy place' it bogs the starter motor because its trying to move. I have checked the linkage, and the centering springs on the lever, and everything is tight, fluids have been flushed, and are full. I have read that there is a valve that gets stuck under the seat. I've been a mechanic for about 20 years, and I would enjoy digging into this, but I would like to find some information on it, and any parts I might need before tearing into it since we use it so much. Any information would be much appreciated.
I'm also curious about wheels and tires, I found that this machine calls for 13 inch diameter 7 inch wide wheels, with about a 23-25 inch tall tire. Right now it has some really sketchy looking wheels and tires on it. They are 13's but the look like they came from a Ford Ranger or something similar. It has a 5 bolt 4.5" circle, just a flat flange mount. I will soon be looking for 4 new wheels and tires for it, so any ideas are welcome. I did see some trailer wheels at our local Runnings Farm and Fleet store, but I doubt they would last.
I know its an older machine, but I've always had a soft spot for neglected machines that have worked so hard for so long. I gotta fix her up =)
Thank you kindly,
Mike.
I am new to this site, and I hope this thread ended up in the right place.
I have recently purchased a 1975 ish Mighty-Mac 8B, it has an Onan 25 hp NHC-MS engine. It runs, and drives but has some irritating things happening. First thing is that when I turn the key, the engine cranks, and the skidder wants to start moving, so you try to correct it by moving the drive lever, but there doesn't seem to be a 'happy place' it bogs the starter motor because its trying to move. I have checked the linkage, and the centering springs on the lever, and everything is tight, fluids have been flushed, and are full. I have read that there is a valve that gets stuck under the seat. I've been a mechanic for about 20 years, and I would enjoy digging into this, but I would like to find some information on it, and any parts I might need before tearing into it since we use it so much. Any information would be much appreciated.
I'm also curious about wheels and tires, I found that this machine calls for 13 inch diameter 7 inch wide wheels, with about a 23-25 inch tall tire. Right now it has some really sketchy looking wheels and tires on it. They are 13's but the look like they came from a Ford Ranger or something similar. It has a 5 bolt 4.5" circle, just a flat flange mount. I will soon be looking for 4 new wheels and tires for it, so any ideas are welcome. I did see some trailer wheels at our local Runnings Farm and Fleet store, but I doubt they would last.
I know its an older machine, but I've always had a soft spot for neglected machines that have worked so hard for so long. I gotta fix her up =)
Thank you kindly,
Mike.
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