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AC 720 Loose Starter Update #2

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Well, back from vacation. Got some good info from an Onan Genrator dealer. According to serial number the engine is for a generator set-4.0BFA/1R-16004A. So it was obviously modified to be put in the 720. Before I left I had the engine cleaned up(found all the oil leaks) and running in my garage. Today, I put it back in the tractor, replaced the battery cables and some other worn wires. I fired it up and it ran for a few seconds. Then the choke cable came off(oops), the choke opened and the engine died. Cranked it some more and it was cranking funny like the timing was off. Then I saw some puffs of smoke coming from the starter. I cranked it a little more and then nothing. So i checked the connections. Juice to the starter, ground is good, Juice to the selenoid with the key in start position. Jumped across the terminals, nothing. Hmm, I think I fried the starter. Anybody have opinions? Does the starter sound fried? Is there a rebuild kit out there for Onan starters? I did find the starter for $135 :( at www.partsfortechs.com. I think I'm going for the Honda conversion.

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Does the engine roll easily by hand? If the carb is flooding and you are getting raw gas into the cylinder, and it will start filling with liquid. Liquid will not compress, so the starter will not turn the engine. This can burn up a starter. This is called hydro-lock. Make sure the engine will turn by hand before assuming it is the starter. Try removing the spark plugs and see if the starter will turn the engine then. If not, then the starter is probably fried.

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You seem to be figting a looseing battle. Not because you can't wrench or don't know, but because there seems to have been so much changed before you got the tractor. This can prove to be qiute a problem if you've never seen what supposed to be there. You have no referance to how it orriginally was. This is one of a few cases where I'd recomend watching for a complete replacement engine from a parted out tractor, or a tractor thats had the engine swap, or yourself go with the engine swap. The only other reasonable thing to do that I can think of is to get a secound tractor thats fairly complete and use it as a base to copy. Provided the secound hasn't had the same treatment.

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