Steve 05merc
Recruit
- Joined
- Jan 22, 2013
- Messages
- 2
I am a first timer here so pls bear with me. Have decided to post this after exhaustive research on my own on the net and speaking to dealers trying to get a straight answer from either Mercury or Yamaha. This engine is one of the same rebadged for Merc. I also have some part no's others did not in their threads. The boat is presently in storage pending a thaw so now is the time to do some research on these questions. So here it goes.
Noticed last fall starter battery not adequately charging, got stranded on the lake with dead battery. (I now intend to hook up a voltage meter on dash to battery (accessory plug) to avoid this in the future; I presume this is the best way to monitor charge of battery? )
Had battery, terminals, etc. checked, confirmed they are ok. Brought boat to local marina. They stated rectifier(s) are likely the problem; from 7-9 volts measured if I recall, not 14-24 volts as others have posted burning wires. I believe the mechanic stated there were 3 rectifiers and likely one has gone bad-so he said?? They did a test on terminals with boat running in water. We were told this is an apparent problem with both Yamaha and Merc engines of this type and vintage. Local marina had a 2004 90 4S Yamaha in the shop with charging issue awaiting parts.
Then we were told the entire Merc harness has to be changed at $575 plus labour because the original has been discontinued? Original discontinued was pt # 804278T11 and replacement is now 804278A12.
Are there any options i.e. replacing with Yamaha parts if compatible or will it just happen again? What is the likely cause; we run stereo, fish finder and minor lights off this starter battery? The only thing I can think is new speakers were hooked up before this started and one wire was shorting out to speaker.
I understand Yamaha part # for 2004 F90 is 67F-81960-12. From some blogging on line it appears the Yami pt is slightly larger than Merc but with same mounting holes. Other difference is 3 blue wires into connector on original Merc vs 2 into Yami with third wire plugged.
As a related side question, and I haven't yet done this but wanted to see if it is possible to also charge my deep cycle trolling battery from the motor off the starter battery with an isolator but now I'm wondering if the charging system is too weak or might catch fire based on some past threads?
Can anyone offer some assistance here as I'm wondering if marina is trying to upsell? Why replace entire Merc harness if only rectifier or regulator is at fault or are they one in the same?? Harness is not burnt or damaged yet; boat and motor have very few hours on them. Can it be replaced with similar Yami part without issues? I see Merc has updated the entire harness, Yami has not - begging the question why?? Could the problem be the Stator beneath the flywheel - it's almost $600 from Merc?
I don?t want to spend this kind of $$ on this to have it happen again. Has anyone got any answers for us?? thanks in advance, Steve
Noticed last fall starter battery not adequately charging, got stranded on the lake with dead battery. (I now intend to hook up a voltage meter on dash to battery (accessory plug) to avoid this in the future; I presume this is the best way to monitor charge of battery? )
Had battery, terminals, etc. checked, confirmed they are ok. Brought boat to local marina. They stated rectifier(s) are likely the problem; from 7-9 volts measured if I recall, not 14-24 volts as others have posted burning wires. I believe the mechanic stated there were 3 rectifiers and likely one has gone bad-so he said?? They did a test on terminals with boat running in water. We were told this is an apparent problem with both Yamaha and Merc engines of this type and vintage. Local marina had a 2004 90 4S Yamaha in the shop with charging issue awaiting parts.
Then we were told the entire Merc harness has to be changed at $575 plus labour because the original has been discontinued? Original discontinued was pt # 804278T11 and replacement is now 804278A12.
Are there any options i.e. replacing with Yamaha parts if compatible or will it just happen again? What is the likely cause; we run stereo, fish finder and minor lights off this starter battery? The only thing I can think is new speakers were hooked up before this started and one wire was shorting out to speaker.
I understand Yamaha part # for 2004 F90 is 67F-81960-12. From some blogging on line it appears the Yami pt is slightly larger than Merc but with same mounting holes. Other difference is 3 blue wires into connector on original Merc vs 2 into Yami with third wire plugged.
As a related side question, and I haven't yet done this but wanted to see if it is possible to also charge my deep cycle trolling battery from the motor off the starter battery with an isolator but now I'm wondering if the charging system is too weak or might catch fire based on some past threads?
Can anyone offer some assistance here as I'm wondering if marina is trying to upsell? Why replace entire Merc harness if only rectifier or regulator is at fault or are they one in the same?? Harness is not burnt or damaged yet; boat and motor have very few hours on them. Can it be replaced with similar Yami part without issues? I see Merc has updated the entire harness, Yami has not - begging the question why?? Could the problem be the Stator beneath the flywheel - it's almost $600 from Merc?
I don?t want to spend this kind of $$ on this to have it happen again. Has anyone got any answers for us?? thanks in advance, Steve