'89 Evinrude 90HP VRO Charging & Tach Issues

fmenezes

Cadet
Joined
Jun 16, 2004
Messages
11
Hi All, I'm new to the forum. I have tried to search for the answer but no luck so I apologize if this is redundant. The boat I bought has an '89(so I was told) Evinrude 90HP VRO, E90TLCEM, with the VRO disabled - oil line plugged - burning premixed fuel. The tach is not working and the battery is not charging. Voltage at battery reads about 12V running or not. I see a few wiring splices and suspect some circuit bypass and/or alteration. The wiring is some what corroded - the T/T will not lift the motor as a couple of wires have broken. The threads I've read cover one problem or the other, but not both. The type of charger is also in doubt. Any and all help to fix these problemswill be greatly appreciated.
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: '89 Evinrude 90HP VRO Charging & Tach Issues

The wiring diagram is in the back of the original factory service manual. A version of this diagram can be found by looking in the "top secret" file, the second thread at the top of page 1 on this forum-it will give the internet address. There are other versions around, such as this website: http://maxrules.com/graphics/omc/wiring/88_89_88_110.jpg. Keep in mind that the trim unit has a sender inside the swivel bracket which feeds a trim gauge at the dash. So identify/separate those two wires from the more important others as you work to restore the function of the trim motor itself. The tach gets it's signal from the combination rectifier/regulator. That device creates the charge for the battery and sends the signal to the tach. Once the tach acts up, it's a really good bet that the combination rectifier/regulator has gone bad (since you also have no charging.) That device on this engine is water cooled and sits atop the block-you'll have to take the flywheel off to change it out. Not rocket science to change it.
 

fmenezes

Cadet
Joined
Jun 16, 2004
Messages
11
Re: '89 Evinrude 90HP VRO Charging & Tach Issues

Thanks for the good info, emdsapmgr. I'm aware of the T/T sender, but before I replace the combination rectifier/regulator I want to be sure that it has an adequate input from the stator. How can I check that?
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: '89 Evinrude 90HP VRO Charging & Tach Issues

That stator is separated into the sets of coils. One set for running the ignition, the others set for charging the battery and sending a signal to the tach. So, you will need to check both sets of coils. If you don't have a factory manual, the CDI website should have the correct information. Personally, I prefer this procedure: voltage output while cranking
 
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