voltage regulator question

trialsguy · Mar 21, 2006

I have received great information and contacted the venders for my parts and will purchase my parts, but I hate to be a parts changer to see if that fixes the problem, so my question is how do I check my altenator and voltage regulator ? I have a couple different fluke meters to work with. No charginging voltage at all, and have been told that it is most likely the regulator but I would like to know before I start throwing cash at it. In my automotive history usally you can bypass the regulator or jumper it to trick it for full charge voltage but this is a little different, since it is a closed unit I cant access it. Is there a way or do I replace parts till it works? Thanks Bob

Forgot to say what its on 1986 YM226D

trialsguy · Mar 22, 2006

YIPPIE!!! I figured it out! Since I am a newbie to these tractors in general, while watching the alternator turn I figured it should be producing voltage of some sort at the plug. I talked to a buddy of mine that said it sounded like a permanet magnet type and should be kinda weird feeling when you rotate it, so I unbolted the alt and give er a spin. Thats when I noticed that the darn thing wasnt turning at all but just the outside part of the pulley, the inside housing part of the pulley was not turning and was locked up sort of just real rough to turn so I figured I would have a look inside and wallah there is a bushing that had chewed up the inside of the pulley housing slightly causing it to rub (very close tolerance in there so 20 thousands off was causing a problem), I just made a shim out of some shim stock and brought it back out away from the assembly and now it works properly.

The orignal problem was a too loose of belt(Improper size) that wouldnt tighten the alternator properly and I think the previous owner tried to pry apart the alt. because the through bolt locknut wasnt tight leading me to believe it was messed with and pry marks on the housing. I think when he pryed on it, one of the bearings may have been unseated slightly causing it to have a looser fit and when he didnt tighten the assembly bolt it just let it get worse.

Jagmandave · Mar 22, 2006

Good for you! It's always gratifying when you figure out a problem on your own, isn't it? Well done!

BTW, you were on the right track, there should be some voltage present at the plug on the alternator, if it's working. Don't know about a "weird feel", but none of the alternators I'm familiar with are permanent magnet type. They require a voltage source (from a battery or whatever) to excite the field and start the power making process........

PS Glad to see another "local" on TBN! Welcome!

trialsguy · Mar 22, 2006

Thanks,
The weird feel for lack of words to describe it would be the magnets holding the windings then with more force they give free causing a soft ratchet type feeling

Soundguy · Mar 22, 2006

It seems as so that some of these yanmar alternators were permanent field dynamos.. and thus charge limited in that effect.. etc.

Soundguy

Onthesauk · Mar 22, 2006

trialsguy, you are now officially one of the resident experts. Be prepared for questions! /forums/images/graemlins/smile.gif

trialsguy · Mar 22, 2006

That is truly a scary thought, I usually break more while being curious than I fix but this did work out good, I just came in from replacing the alt. belt, man talk about a tight fit, would be easier I think if you were to remove the radiator. I had the parts guy match my belt. really needed about a 1/2 inch shorter belt to put me in the middle of my adjusting slot but this is working great, just need to get the fuel bowl assembly on order, it doesn't shut off and the filter is missing and the bowl is cracked, nothing a inline filter didn't fix and a little jb weld installed by the previous owner wouldn't cure. Since I got the tractor and emplements for a great price I figured I better get it back up in tip top shape