Need more info

E

emtmike

Seaman Apprentice
Joined
Sep 1, 2009
Messages
34
I have 2 questions. Like that's a shock, me with questions. I have a Mercury Outboard 90 Hp and I cant find any information on it. What year, parts info, stuff like that. I have found some sites that charge you $$$$ for info. I am on a very low budget for this project so any free info I can find the better. My second question is how do I know if the motor is charging the battery's. I have 2 Sears marine battery's and they just don't charge. They work OK at the first of the day after being on the charger all night but as the day goes on they die. Can anybody help me with these questions before I come up with more?
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Need more info

To find the year we need a serial number, to check for charging put a voltmeter on the battery and start the engine if the voltage don't increase at high idle the rectifier is probably bad and we can furnish you with the test if you haver a OHM meter.
 
S

sschefer

Rear Admiral
Joined
Nov 13, 2008
Messages
4,530
Re: Need more info

Online parts lookup can be done right at www.mercurymarine.com or www.crowleymarine.com.

Use the serial number in your parts search and you'll hit on your exact model. You have to go through a little sign up procedure for Merc but eventually they'll let you look at the parts list.
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Need more info

Your engine was built in 1986. Here's a rectifier test.
scan-4.jpg
 
E

emtmike

Seaman Apprentice
Joined
Sep 1, 2009
Messages
34
Re: Need more info

OK With the new battery, that I needed anyway, I get 12.78 on the floor, when I start the motor I get 12.8. I think I have a problem.
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Need more info

Yes, these a problem, check the rectifier and when the 2 yellow wires are off make sure there is continuity between them.
 
E

emtmike

Seaman Apprentice
Joined
Sep 1, 2009
Messages
34
Re: Need more info

How do I do that. I am good a doing things I just dont always know how.:confused:
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Need more info

Do you unerstand the rectifier test, if so while the wires are off the rectifier just connect the OHM meter between the 2 yellow wire that come from under the flywheel and see that there is a reading (continuity) through them.
 
E

emtmike

Seaman Apprentice
Joined
Sep 1, 2009
Messages
34
Re: Need more info

OK I will give it a try. Stupid question I am sure but.............I do this with the motor running right? And what setting do I use on my meter?
 
E

emtmike

Seaman Apprentice
Joined
Sep 1, 2009
Messages
34
Re: Need more info

OK I took my handy dandy meter and set it to OHMs. I unhooked both yellow wires from the rectifier and hooked them to my meter. I got a reading of -0 What next?
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Need more info

If the meter did not move when hooked to the wires and if it does when the 2 meter leads are hooked together the stator is bad, it should show some movement when hooked together or to the wires.
 
L

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Need more info

Requires removing the flywheel and the wires from the switch box and rectifier
 
You must log in or register to reply here.
Top