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1989 evinrude 150 hp xp tach not working

morav

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Tach is not working on a 1989 evinrude 150xp ranger 363v. Engine running smooth and has full power. Tach reading was jumping, die, work good, now it is dead. I need a procedure to troubleshoot. I bought a new marine starting battery, out of the store measured 13.7 volts, installed in boat running battery measured approx 17 volts. I had the tach problem before installation of new battery.
 
Re: 1989 evinrude 150 xp tach not working

At 17 volts it looks like your voltmeter is incorrect or the voltage regulator has a problem. The voltage regulator also operates your tach signal. Start the engine and check the gray wire on the tach for volts, it should show a difference in voltage when the engine is idling and when it is running faster. From your other discriptions of the problem it sounds as if your tach might have just bit the dust.
 
Re: 1989 evinrude 150 xp tach not working

(Testing Tachometer With Water Cooled Regulator/Rectifier)
(J. Reeves)
A quick check is to simply plug in a another new tachometer as a piece of test equipment. If the new tach works properly and the old tach didn't, obviously the old tach is faulty.... but usually boaters don't carry around a spare tach (see below).

A faulty rectifier wouldn't damage the tachometer, the tachometer simply wouldn't work. This is due to the fact that the tachometer operates off of the charging system and the rectifier converts AC voltage to DC voltage, enabling the charging system. A faulty rectifier disables the charging system, and the tachometer simply doesn't register.

However.... those water cooled regulator/rectifiers that are used on the 35 ampere charging systems (and some others) bring into play a different type problem, and as you've probably found out, they are really a pain to troubleshoot via the proper procedure. There's an easier way.

The tachometer sending/receiving setup operates off of the gray wire at the tachometer. That same gray wire exists at the engine wiring harness which is connected to the engine electrical terminal strip. You'll see that there is a gray wire leading from the regulator/rectifier to that terminal strip, and that there is another gray wire attached to it. That other gray wire is the wire leading to the tachometer which is the one you're looking for.

NOTE: For the later models that DO NOT incorporate a wiring terminal strip, splicing into the "Yellow Wire" mentioned will be necessary.

Remove that gray wire that leads to the tachometer. Now, find the two (2) yellow wires leading from the stator to that terminal strip. Hopefully one of them is either yellow/gray or is connected to a yellow/gray wire at the terminal strip. If so, connect the gray wire you removed previously to that yellow/gray terminal. Start the engine and check the tachometers operation, and if the tachometer operates as it should, then the regulator/rectifier is faulty and will require replacing. If the tachometer is still faulty, replace the tachometer.

If neither of the yellow wires from the stator is yellow/gray, and neither is attached to a yellow/gray wire, then attach that gray tachometer wire to either yellow stator wire, then the other yellow wire, checking the tachometer operation on both connections.

I've found this method to be a quick and efficient way of finding out which component is faulty.... the tachometer or the regulator/rectifier. It sounds drawn out but really only takes a very short time to run through. If the water cooled regulator/rectifier proves to be faulty, don't put off replacing it as they have been known to catch on fire with disastrous consequences.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
Re: 1989 evinrude 150 xp tach not working

I disagree with J Reeves if you hook up your tack grey wire direct to yellow/gray from stator your bypassing the rectifer and feeding ac/dva volts into your tachometer.Not good Ben
 
Disregard my last post,after some thought I agree with JReeves it will work, in fact the older mercury motors are wire that way for a tachometer.
 
Had the exact problem on my 89 175 , your regulator has took a **** and needs to be replaced.On your terminal if you do touch your grey wire on either the solid yellow wire/ yellow and grey and your tach suddenly works is definetly another sign. The over charging is a sure sign that only the rectifier side is working in your voltage regulator/rectifier. You do need to check your DVA readings from your stator if able to . I replaced both the stator and reg/rec when I had my flywheel off. if you have a radio shack and a old radio store near by and can solder i can tell you how to make a DVA adapter.
 
Disregard my last post,after some thought I agree with JReeves it will work, in fact the older mercury motors are wire that way for a tachometer.

All of the older alternator equipped Evinrude/Johnson engines that are simply equipped with a rectifier, rather than a water cooled voltage regulator/rectifier assembly, have their tachometers wired in the same manner, hence I knew my instructions were valid.

Don't disagree with me... I get madder than hell!;)
 
Joe I did not read your entire post , but followed the same diagnosis for my water cooled reg /rectifier as you posted and ruled that mine was faulty.
The high charge was also a problem I had. Good info...
 
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