temichels Posted May 24, 2006 Posted May 24, 2006 Hello, I have a 12 hp b & S engine 300421 approximately 1970. I have purchased a brand new battery, but it drags even with a full charge, the only way I can get it to turn all the way over is if I use my truck to jump it and even then the truck has to be running to provide enough juice to turn it all the way over. I have replaced many wires, cleaned all the contacts, checked the brushes in the start-gen, it has a new voltage reg. The engine is tight but I can turn it by hand with a little muscle. It just seems to me that a 590 cca battery would turn it over with no problem. I know I am kinda vague, but does anyone have any suggestions or Ideas on this. Thanks Tim
MrSteele Posted May 24, 2006 Posted May 24, 2006 Starter dragging is usually inside the starter. You checked the brushes. What condition is the armature itself in? The commentator, where the brushes run, may be dirty to the point that it is shorted. Clean the commentator with very fine sandpaper, blow it off with air before reassembly to get the sand particles out, or they will continue to sand when you run the starter. Check between the poles to see if they may be filled with carbon. If so, carefully scrape it out and again, blow it out with air before reassembly. Either of the above may solve your problem. While you have the armature out, you may want to have it checked for continuity at a local automotive electrical shop. If there is a break in the armature, you will not be able to see it, but will have to replace the armature.
RayS Posted May 24, 2006 Posted May 24, 2006 Is the voltage regulator that you replaced the correct one. There are differences.
ehertzfeld Posted May 25, 2006 Posted May 25, 2006 quote:Originally posted by temichels The engine is tight but I can turn it by hand with a little muscle. That don't seem right! Are you sure it's not on the way out? I would pull the head, and see what it looks like. Elon
UCD Posted May 25, 2006 Posted May 25, 2006 A high resistance connection will cause this problem also and is the most common cause of it. Check all connections both at the battery and at the starter and battery ground. Remove both cables from the battery and clean the battery posts and cable terminals. Remove the other ends of both cables and clean the terminal ends and where they connect to the engine/frame ground and starter. The next most common cause is a bad starter (as mentioned above) including bad bushings/bearings in the starter. If you aren't up to the testing and repair to the starter remove it and take to a good starter/alternator repair shop.
HubbardRA Posted May 25, 2006 Posted May 25, 2006 I'm with Elon. Sounds like something in the engine itself. Most of my engines can be turned with one hand on the crankshaft. They don't need any significant muscle to turn them, unless they are sitting against compression.
richp Posted May 25, 2006 Posted May 25, 2006 I agree with Maynard, I have had ground cables that look fine, but at one time got overheated and have way to much resistance.
OldFarmTractor Posted May 25, 2006 Posted May 25, 2006 Throw a voltmeter between the starter connection and ground. If you get less than Volts or so when it is cranking, you probably have wire problems.
temichels Posted May 25, 2006 Author Posted May 25, 2006 Thank you all for your input...I got this tractor from my dad, he had it sitting outside for some time. I took it completely apart (except for the engine) sand blasted and repainted it. I too was thinking it was a ground issue. I have replaced all the cables but maybe there is a connection problem at the engine/frame. I am more inclined to think the starter/generator (even though the brushes look good) has a lot of rust in it and needs cleaning. It could also be the engine, but I am hoping not, if the start/gen rebuild at my local shop does not solve the problem I will go to the engine. again thanks all Tim
Ronald Hribar Posted May 26, 2006 Posted May 26, 2006 I tightened the belt up on my s/g and that made it harder to turn over. But not as hard as yours seems to be
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