BroadmoorMan Posted December 25, 2006 Share Posted December 25, 2006 I just bought a 728 thats in ok shape but my other tractor is in better shape. I was wondering if I did a engine swap then what would I have to do with the electrical. The other tractor is a 707. Link to comment Share on other sites More sharing options...
RayS Posted December 25, 2006 Share Posted December 25, 2006 Not sure what you would have to do, but welcome to the club. Link to comment Share on other sites More sharing options...
MarksA-C Posted December 25, 2006 Share Posted December 25, 2006 What kind of engine are you planning on swaping with the 8 or 7hp briggs? My A/C 610Lt (Same as Broadmoor) has a newer 12hp and It didn't need any changes. Both the engines were briggs so the mounting holes were the same, and the wiring was the same. Link to comment Share on other sites More sharing options...
BroadmoorMan Posted December 25, 2006 Author Share Posted December 25, 2006 8 h.p. Link to comment Share on other sites More sharing options...
BroadmoorMan Posted December 25, 2006 Author Share Posted December 25, 2006 The engine that was on the 707 was a 8 h.p. Briggs from 96. The one I might put on is a 8 h.p. Briggs from 88. The difference is that the one from 96 had a starter generater and the one from 88 is a gear drive engine. Link to comment Share on other sites More sharing options...
rsnik Posted December 25, 2006 Share Posted December 25, 2006 How it works in theory (I only know this from outboard motors, correct me if I am wrong) is the ignition switch is connected to a kill wire to ground out the ignition and stop the engine in the off position and also a hot wire to kick the starter solenoid when you turn the switch all the way over to engage the starter. In the on position the kill wire circuit is simply open and not grounding out the ignition. The ignition switch also provides a spade to attach the wire providing 12 volt regulated voltage from the charge coil under the flywheel and get the voltage into the battery/accessory system. I think these later, gear starter engines have several coils around the perimeter of the flywheel that get charged by magnets in the flywheel. There is an ignition coil, a charge coil and a trigger coil. The ignition coil I think generates AC voltage that gets rectified into DC voltage and runs through the coil which is triggered by the trigger coil under the flywheel (this is different from battery ignition in that the ignition and battery electrical systems are separate). The charge coil under the flywheel generates AC voltage that gets rectified and regulated to charge the battery and provide accessory power and is separate from the ignition system which makes it's own voltage for spark with the ignition coil under the flywheel. Sooo, basically you need to have a wiring code for the new engine and connect the wire which provides regulated 12 volt power to the ignition circuit (probably at the ignition switch), connect the kill wire to the spade on the ignition switch which will provide continuity to ground with the switch in the off position and connect a wire from the positive ignition pan head terminal on the starter relay to a spade on the ignition switch which will provide 12 volts to kick the starter relay when the switch is turned all the way over to engage the starter. I have a 728 that is perfect except no engine and would like to find a later type 8 HP. The starter/generator on my 717 just went bad. I have a spare or I would be looking for 2 later generation engines. rsnik Link to comment Share on other sites More sharing options...
mowerman1193 Posted December 26, 2006 Share Posted December 26, 2006 I belive the newer motors have the mounting holes in the engines for mounting a Sarter Gen. I would think you should be able to just swap starters ect. and use the existing wires from the tractor..I could be wrong as I have never done this but if thats possible thats what I would do.. Link to comment Share on other sites More sharing options...
bud119195 Posted December 26, 2006 Share Posted December 26, 2006 Both 8 hp engines are the same . Use the pulleys and mounting hardware for the starter generator, you might also need to change fly wheel. Then you wont have to do anything with the wiring. Link to comment Share on other sites More sharing options...
TomSchmit Posted December 28, 2006 Share Posted December 28, 2006 You can change over the entire wiring harness from one tractor to the other! Tom Link to comment Share on other sites More sharing options...
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