94 Evinrude 200 Vindicator
I have had tach problems for a good while now. The old one (factory) would read 5500 rpm while running half throttle at 30mph. Bought a new one and now the new one works periodically. It will be working fine for several mintues and then go to zero for a few minutes and then return to normal. Sometimes when I hit the tilt/trim, the tach will drop 1000 rpms and then return to normal or go to zero. Any ideas?
To our troops
If you have wing nuts on the cranking battery get rid of them and install Stainless steel hex nuts with SS lock washers or use SS nylon insert nuts. Put a meter on the battery before charging and take an initial reading. Start the motor with cooling applied and monitor the meter reading it show a charge through the the RPM range stopping at roughly 14.0 VDC. It should show no less that 12.6 VDC with the motor running. If so have your stator tested but the suspect is generally the voltage regulator/rectifier.
I do have wing nuts. I did put a washer and lock washer under the wing nuts thought. But I will change them as recommended. I have been watching my volt meter lately and it is showing 14-16 volts while running, so it looks like the motor is charging...
Is the SS nuts a fix for a bad connection type issue or a means to do the voltage test?
14-16 volts is too high, I suspect a bad rectifier. You will boil that battery running those high volts.
Sharkey, the ss lock washers and nuts are to keep from having a loose connection, which will eventually burn up the rectifier......
Thanks for the advice guys. Does anyone know if the flywheel has to be removed to replace the rectifier on this particular motor?
Model#200STLERK
Nope just the power pack. How's your water pressure? Reason I ask is the VR is water cooled. But get rid of the wing nuts.
Water pressure is between 20-25 at cruising speeds. I was just made aware that the rectifier is water cooled. I'm no boat mechanic, but pretty mechanically inclined, is this a difficult repair?
BTW....Do you know what size SS nuts I need for the battery? It is at the lake, so I don't have immediate access to the battery....
Thanks for all the input
While on the subject of rectifiers, what is the job of a rectifier and what happens to the motor when a rectifier totally goes out? Sorry for the dumb question...Just trying to learn more about motors.....
I'm no guru by no means, but the gurus on here have taught me a thing or two. I believe the + post takes a 3/8-16 nut while the neg post takes 5/16-18.
The rectifier converts ac power from the stator to dc and regulates it to charge the battery. When the regulator goes out, you lose tach signal and charging, also they can short and catch fire. Hope this helps.
Thanks Bass,
I guess that is why I have seen mentioned on here for folks to be careful while changing out stators in fear of being shocked. Another dumb question, does the stator store energy, or is it safe to work on all these items once the battery is disconnected.
Nope once it is off it is off. No shock hazzard.
"...what is the job of a rectifier...[?]"
See
http://continuouswave.com/whal....html
for a thorough description of an outboard motor electrical generating system.
Thank for the info guys and appreciate the article Jim. Worked on a few cars in the day, but kinda new to boat repairs. Since my boat/motor is 16 years old, I'm getting a few more repairs whether I want them or not.......lol
BTW, I am in possession of stainless locking nuts for the battery. Thanks for the advice guys.
I'm new to this board, but i have the same issue with an 86 150xp and was trying to find on here what could possibly doing it, my tach works when it wants, and when it seems like its working fine, hit the trim tab and boom it goes down.
from a post almost 4 years ago, a guy had the same issue and he found the problem to be a wire in the remote box was worn, and was grounding out each time he was to hit the trim tab causing the tach to fail/go nuts. I'm going to check this on mine, if you dont find the problem with current suggestions, might be something to check.
http://www.bbcboards.net/zerothread?id=96837
Last October my tach started doing the same thing and then finally just stopped working all together. I assumed I had a bad tach or wiring and figured I would replace it soon. Unfortunately while cruising across the lake the motor cuts out and what I thought at was steam was coming from under the cowel. I pulled off the cowel thinking I had blown a head gasket to see the voltage regulator white hot and catching fire. I disonnected all of the batteries, hit it with the fire extinguisher (that was a waste of time), and then put the cowel back on hoping to starve it for oxygen. We got towed back to the dock before the fire started to eat through the cowel and the fire department got it put out.
A couple days later I called the marina I prefer to get an estimate on the damage. After telling the mechanic that my motor had caught fire and that I wanted to bring it in for an estimate he asked me if the tachometer had started acting weird or stopped working. Keep in mind I had not described anything other than the motor had caught fire so when he said that it sounded like the voltage regulator had gone bad I was quite surprised. If I had known that the tachometer going crazy and finally not working had been an indicator of that type of trouble I would have trolled it back to the dock and had it looked at immediately. So just something to keep in mind for those who think the tach is going bad, it may not be the tachometer at all and could be an indicator of big trouble.
Well,
I ran a new wire from the back of the tach to the stator as a test. The tach still acts crazy, really bad when I hit trim. So I'm assuming it is time to replace the stator. I'm still confused because the stator is putting out enough to charge the battery. I also looked and don't see any bad wiring around the shifter to indicate a short with the trim wiring...
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