mooman3121 58 #1 Posted August 15, 2019 Hi all! I recently purchased a 702 that had been sitting in a barn for several years. It was not in running condition at the time so I only paid attention to the major things- motor turn, trans shift, body condition, etc. When I got the machine home and actually started cleaning and disassembling I discovered that the new then battery had been hooked up backwards! Wow no wonder the guy couldn't get it to run- Now that I have it running I don't think that the generator is working as I only get a faint glow on my tester coming out of it when running. My question is could the battery being installed backwards have damaged the charging system and if so how? I priced a new regulator and it wasn't cheap, so would like any help on what to do.... Thanks! 1 Share this post Link to post Share on other sites
pfrederi 18,410 #2 Posted August 15, 2019 Generators need to be polarized. That is accomplished by flashing the Armature terminal to battery voltage. However as you have a Starter Generator that is done automatically when you start it. You are applying battery voltage to the armature terminal. Voltage regulators can fail from corrosion bad contact etc.... What is battery voltage when shut down? Should be 12.6 for fully charged battery Voltage when running?? Should about 14. Take a jumper wire and ground the "F" terminal on the generator You should hear the engine slow a bit and voltage should jump up to 14. if it does then you r regulator is bad. if it doesn't then the charging field coil is suspect 4 Share this post Link to post Share on other sites
stevasaurus 23,117 #3 Posted August 15, 2019 Hi...thought this would be better served in the "Engine Section". I'm not sure if the guy hooked it up backwards and never ran it...if it would cause any harm. Looks like Paul jumped in before I showed how little I know. Listen to what Paul says. 2 2 Share this post Link to post Share on other sites
pfrederi 18,410 #4 Posted August 15, 2019 Generators do not care if they are positive or negative ground (think old farm tractors) Hence the requirement to flash polarize them. Current saddle mount regulators say pos or neg ground (not sure about the ones from 40+ year ago0. The PO of my Farmall M put a battery charger on it for several days back wards...(She is positive ground). other than screwing the battery did no harm to the generator or cutout regulator. 3 Share this post Link to post Share on other sites
mooman3121 58 #5 Posted August 15, 2019 Ok thanks all! I had never experienced this kind of deal before- Am well aware of positive ground systems but didn't know if special components required as I am definitely not a sparky! thanks again..will check it out and let you know what I find..... 1 Share this post Link to post Share on other sites
953 nut 58,458 #6 Posted August 15, 2019 Be sure to clean and tighten all electrical connections including grounds. A little corrosion can make a big difference. 2 Share this post Link to post Share on other sites
mooman3121 58 #7 Posted August 15, 2019 I hear ya 953! but some of those terminals on the back certain components you KNOW that you will not remove without twisting off! spraying lots of blaster every day! Think connection is still good but- yes would like to be sure! thanks! 1 Share this post Link to post Share on other sites
mooman3121 58 #8 Posted August 15, 2019 yes! for sure! should have seen the work to adjust the clutch and brake! deserves a times two ! yep! by the way how does one ever disconnect that clutch shaft that goes to the other side of the frame without totally disassembly? newbie wonders.... Share this post Link to post Share on other sites
Achto 28,964 #9 Posted August 15, 2019 @mooman3121 Check psep.biz for a voltage regulator if you need one, they have after market ones for around $20. It will be in the Kohler/ starter section. 2 Share this post Link to post Share on other sites
mooman3121 58 #10 Posted August 15, 2019 Thank you much Achto for that! was quoted way more for that regulator! 1 Share this post Link to post Share on other sites
mooman3121 58 #11 Posted August 16, 2019 Ok- did the test Paul recommended , voltage at rest not running was 12.5- voltage when running drops to 12.2. When I ran jumper wire from the field pole to ground it had no effect- voltage stayed at 12.2 and engine was unaffected. So must be the generator itself has the issue? Share this post Link to post Share on other sites
pfrederi 18,410 #12 Posted August 16, 2019 2 minutes ago, mooman3121 said: Ok- did the test Paul recommended , voltage at rest not running was 12.5- voltage when running drops to 12.2. When I ran jumper wire from the field pole to ground it had no effect- voltage stayed at 12.2 and engine was unaffected. So must be the generator itself has the issue? Assuming all the wiring is OK no bad or corroded connections then it is most likely a failed field coil (or something else internal to the Genny.) Note the regulator may still be bad also I do most of my own mechanical work but Generators go to a local Starter generator shop. Undercutting an armature is not in my skill set. They will also insure that your regulator is OK as both regulator and Genny may have failed. 1 Share this post Link to post Share on other sites
mooman3121 58 #13 Posted August 16, 2019 Hey Paul! Yes I took apart and cleaned all the connections before testing so while I am bummed that I now have to send it out and spend money on it, at least it will eventually get working right again! thanks for your help! 2 Share this post Link to post Share on other sites
