Merc 1000 100hp draining battery

[kmvboat]

I just bought a 63 boad with Mercury 1000 with 100 hp. It runs great bu took it out to the lake with brand new battery and it drain that down in about 1.5 hours of usage ( 5 gal of gas). Needless to say, I had to be towed about 4 miles to the dock. <br /><br />Where should I start. I know a lot about cars but this boat thing is brand new to me. This is my first boat... Help...

 

[Laddies]

Re: Merc 1000 100hp draining battery

Test the rectifier

 

[Clams Canino]

Re: Merc 1000 100hp draining battery

Yep...<br /><br />-W

 

[kmvboat]

Re: Merc 1000 100hp draining battery

Is this the three plates saperated by some sort of magnet or something??? I have a meter but not sure how to test it. Thanks so far...

 

[GA Paramedic]

Re: Merc 1000 100hp draining battery

There are two wires coming from the stator (just under the fly wheel) to the rectifier. Mine are two yellow wires. set your volt meter to ac volts and you will be looking for somewhere around 260 or so.

 

[GA Paramedic]

Re: Merc 1000 100hp draining battery

BTW, the rectifier's job is to change the voltage from AC to DC. that is how you should be able to test the rectifer given that your stator is working.

 

[kmvboat]

Re: Merc 1000 100hp draining battery

Thanks so far. My starter has just been rebuild last week and works fine. I will check reading measurements tonight. If it does NOT read around 260v then what should I be looking for next or what needs to be changed out? Thanks again.

 

[Clams Canino]

Re: Merc 1000 100hp draining battery

If you have an old plate type rectifier, just change it out for the one for a 1984-88 Merc 115.<br /><br />Those old ones leak back EVEN when they are working right. Just save it so you can keep it all original if a collector ever wanted it.<br /><br />Also the stator outt read almost a dead short on the ohm meter like 2-4 ohms. Where is that 260 volt reading number coming from, sounds WAY too high.<br /><br />-W

 

[Chris1956]

Re: Merc 1000 100hp draining battery

KMV, The rectifier is a "Bridge" of four diodes connected together. If your rectifier is original, you should see a small square device which has three wires connected to it. Two of these wires should run to the stator (under the flywheel). The other wire will connect to the "hot" wire, which is ultimately connected to the battery Plus pole. A quick test is to disconect the motor harness or positive battery terminal. Now set the ohmmeter to RX1 resistance, and put one lead on the red (hot) wire and the other lead on the wires from the stator. You should read infinite resistance. I would think your rectifier will have a short from the positive wire to one of the stator wires.

 

[kmvboat]

Re: Merc 1000 100hp draining battery

Okay, took me awhile but finally got around to do some test measurements and here's what I found:

Chris1956, I put one lead on one of the yellow wire going to the plates and the other to the other side of the plates which is leading to the hot (+) side. I'm going to reference the two yellow wires as engine side and boat side eventhough they're next to each other. Anyway, on the one that is on the engine side reads 1.4-1.5 ohm where the other one reads .8 - .9 ohm. Does this indicate a bad rectifier???

Clamscanino, If I move to the 1984-88 Merc 115 type of rectifier, will this be a one wire in an two wires out and simple drop in without major mod? Please let me know. I got a new battery and would like to get her on the water again. Thanks for all your help so far.

K.

 

[Clams Canino]

Re: Merc 1000 100hp draining battery

It's the 2 yellow in and the one red out... just like your old install. the case grounds to chassis to complete the deal. Why another new battery - easier than just charging the one that was new on June 6th??

 

[Bob_VT]

Re: Merc 1000 100hp draining battery

Just a few words of advice-

Clamscanino knows exactly what he is talking about - his advice is at the top of my list.

If you can afford to boat and play - spend a little money and order a manual for your motor. It will save you in the long run.

 

[kmvboat]

Re: Merc 1000 100hp draining battery

Clam,

Oh... the battery is from Walmart so it is easier to just get a new one since I don't have a charger unit yet.

Okay... Will either one of these part # from the link below work for my rectifier replacement. I have a straight 6 Kiekafer from 1963? Rectifier Part#'s in questions are 816770-1 or 78614A1. If not, please advise on where I can get one. Thanks.

http://www.iboats.com/bbboard/bbBoard.cgi?a=redirect;url=http://www.oldmercs.com/ignsys.html

 

[Clams Canino]

Re: Merc 1000 100hp draining battery

816770-T is prolly the best deal. You can buy the same thing at the Merc parts counter faster, just ask for a rectifier for a 1987 115.

It cracks me up how many people here look to oldmercs.com (and reccomend them) as the answer to all prayers. All they are doing is cross referencing existing parts from Merc/Sierra/CDI/Rapair to the older mercs to make it easy for the uninitated (or lazy) to buy stuff for more money. As far as I know they don't have an exclusive on any known part. But they do make it easy to get stuff quick.

-W

 

[kmvboat]

Re: Merc 1000 100hp draining battery

Clam,

I finally got the 816770-T rectifier. It has three posts.
One is lable + for the hot side but the other two has no lable on them. Does it matter which one of the yellow wires goes on one of these two post? Please let me know. Thanks.

K.

 

[Clams Canino]

Re: Merc 1000 100hp draining battery

No it does not matter. The yellow are the AC feed.

-W

 

[kmvboat]

Re: Merc 1000 100hp draining battery

Okay... Got the new battery, put in the new rectifier. Boats starts and runs perfect for about an hour then just quit. Can't restart it anymore. The battery still have plenty of juice to turn the starter but the engine will not fire and spray in the starter fluid did not help. Do you think its the Distributer??? I'm close to giving up on this old boat...


...Had to get the paddle out. Fortunately it was only about 600 yards from the dock.