moe1965 737 #1 Posted July 15 I'm having a starter generator looked at for my 857. The shop I took it to is still trying to figure out why it's not charging and he is learning towards the voltage regulator might be bad. He said all the ones he is seeing lately that he gets for replacements are pretty much all junk. Any of you have a good luck finding a good replacement.. thanks in advance Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,040 #2 Posted July 15 Original regulator Kohler number is B-275703 This one from Stens should work https://www.bantasaw.com/catalog/viewproduct.asp?i=&p=1336 Share this post Link to post Share on other sites
Handy Don 12,210 #3 Posted July 15 (edited) 2 hours ago, moe1965 said: I'm having a starter generator looked at for my 857. The shop I took it to is still trying to figure out why it's not charging and he is learning towards the voltage regulator might be bad. He said all the ones he is seeing lately that he gets for replacements are pretty much all junk. Any of you have a good luck finding a good replacement.. thanks in advance I'd start with asking if the service person knows how to diagnose the S/G and regulator. It isn’t complicated but does require a sense of how they are supposed to work and a few tools--shops that do generators can do this in their sleep. Basically you want to know if there is a wiring issue, if the generator is putting out voltage, and if the regulator is properly controlling the voltage being generated--in that order. If this is a “throw parts at it” person, you could be in for an expensive and frustrating ride. IMHO the newer, non-adjustable regulators are a bit of a crap shoot. Some work really well and some don’t--but adjustment is nearly impossible. If you have an adjustable model that doesn’t have any obvious faults, I’d try to keep it. The most likely issues for that vintage are: 1. The brushes and/or the commutator (on the armature) in the S/G are not making good contact. Replacement brushes & springs are readily available and the commutator can be lightly turned down (if really badly scored) and the mica separators undercut if they are flush with the contacts. (While you have it open, replacing worn bearings is cheap and easy.) 2. The spring-loaded points on the regulator (there are two sets) need cleaning (NOT with sand paper--use a slightly curved, very fine riffler file) and possibly a reset to adjust them to the proper spring tensions for the cutoff/current limiter, and the voltage regulator. There are videos on the interweb describing repairs to both of these. Other far less likely possibles (unless someone has messed with it): - a short or grounding of a coil in the body or armature of the S/G (using ANY kind of solvent to clean the inside of an S/G can dissolve CRITICAL insulation and totally ruin it--use compressed air, carefully) - a shorted wire from the positive brush holder or brush wire to the shell of the S/G - a short or grounding of a coil in one of the regulator “relays” -- (same warning about solvents applies!) Read the attached files for more info! Good luck.🙂 Delco Remy Regulator Service Bulletin 1R-116.pdf Delco Remy Service Bulletin 1R-111.pdf Delco Remy Service Bulletin IMG-150.pdf Edited July 15 by Handy Don 2 Share this post Link to post Share on other sites
moe1965 737 #4 Posted July 16 I picking up the starter generator today it was going to cost me 350 to get it fixed. I didn't pay that much for the tractor. Any how he told me it was putting out 8 amps I think I'll find another solution Share this post Link to post Share on other sites
Handy Don 12,210 #5 Posted July 16 (edited) 4 hours ago, moe1965 said: I picking up the starter generator today it was going to cost me 350 to get it fixed. I didn't pay that much for the tractor. Any how he told me it was putting out 8 amps I think I'll find another solution Yikes! Was there an explanation of what you’d get for $350? 8 amps is more than adequate to charge a battery for starting and running (assuming it’s at 13.5 or more volts) unless you have a lot of electric add-ons sucking juice. So the generator is probably ok. So that’d lead to testing the regulator. If you feel confident doing diagnosis and repair yourself, folks here can give you some guidance. Otherwise, you can always check with A to Z (in the vendor list) to see what a known-to-work regulator would cost you. A new one is about $30-50, depending on the source and quality. Edited July 16 by Handy Don 1 Share this post Link to post Share on other sites
adsm08 2,046 #6 Posted July 16 8 amps is plenty. I have a factory amp meter (real amp meter, not a misnomered volt meter) on my 855 and it only goes to 5 and I've never seen it run above 2.5. Find the F terminal on your generator. Then get it installed and all hooked up. Clamp the leads from a volt meter to your battery terminals with some alligator clips. Clamp another jumper wire to the field terminal on the generator. Start the engine, take a voltage reading. Then, with the engine still running, ground the field terminal and take another reading. Do this step quickly, like 5 seconds or less quickly. The reading should have gone up, near 15 volts. This is called a "full field" test and will test the full potential output of the generator. It takes the regulator out of the loop and so if the generator can get up above 13.5 to 14 volts the regulator, or its wiring, are the issue. 3 Share this post Link to post Share on other sites
moe1965 737 #8 Posted July 17 I'm going to do a test on this weekend like you said Handy Don. For what I use the tractor for it sounds like it will charge enough. I just use it once a year to put around at a steam engine and small tractor show and occasionally ride down the sidewalk around where I live pulling a small trailer and pick up all the garbage the kids throw out the window which is about twice a week. 1 Share this post Link to post Share on other sites
