1963 Mercury 650 restoration

DeepCMark58A

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On a Mercury of that vintage I would expect some bad wires, I would replace all the fuel lines, rebuild the fuel pump including the the check valves. I would have new seals and bearings installed in the lower unit and new impeller in the water pump, and new rebuild the carbs. Do yourself a favor and use genuine Mercury parts for things like the fuel pump, oh and go buy a manual, the parts are much easier to find of you have the part number. Oh and take lots of pictures to document the disassembly.
 

DeepCMark58A

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I also want to add that do not let the age of the motor fool you, if properly rebuilt they are very dependable. That being said it is a learning process to getting them adjusted just right. You are making the right decision in choosing a vintage Mercury and keeping it period correct.
 

racerone

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That magneto is a wonderful simple device !!---------Just look at the price of parts for the last years of a " tower of power " CD ignition.-------Coils are $87 each and there are 6 of them.----Stator is $300---trigger$240----Switch boxes are $314 each and there are 2 of them.---------The Magneto on the 650 models requires that the owner learn how to clean / set points once a season !!----A zero $ required unit in most cases..-----They do not build them like they used to.-----Newer does not always mean better for those on a budget.
 

MPrimeaux

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On a Mercury of that vintage I would expect some bad wires, I would replace all the fuel lines, rebuild the fuel pump including the the check valves. I would have new seals and bearings installed in the lower unit and new impeller in the water pump, and new rebuild the carbs. Do yourself a favor and use genuine Mercury parts for things like the fuel pump, oh and go buy a manual, the parts are much easier to find of you have the part number. Oh and take lots of pictures to document the disassembly.

Noted DeepC. Thanks for the advice.
 

MPrimeaux

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That magneto is a wonderful simple device !!---------Just look at the price of parts for the last years of a " tower of power " CD ignition.-------Coils are $87 each and there are 6 of them.----Stator is $300---trigger$240----Switch boxes are $314 each and there are 2 of them.---------The Magneto on the 650 models requires that the owner learn how to clean / set points once a season !!----A zero $ required unit in most cases..-----They do not build them like they used to.-----Newer does not always mean better for those on a budget.

That helps me a bunch Racer! Puts things into perspective. I get nervous and start second guessing myself when I don't know the details.
 

MPrimeaux

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There is no path from the rectifier to the magneto. The key switch removes a ground to the stud on the side of the magneto to run and grounds the stud to shut the motor off. On/off is by ungrounding and grounding the points wired to the stud.

Now I understand. Thanks a bunch GA. I'm guessing there will be a NO button/switch to kill the engine on the motor if I start it with the pull cord?
 
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GA_Boater

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Sure there is a kill switch. Here is a pair of mine;

61IMKpdiL2L._SX425_.jpg


Clip one end on the magneto stud and let it hang. When it's time to shut the motor down, touch the other end to ground.

Caution - Do not touch the bare clip to any body part while the motor is turning, either cranking or running. The result is shocking!
 

merc850

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Well if you start the motor without a charged battery hooked up you will destroy the rectifier (although it might be done
already). Just running a motor without understanding the systems is why they're damaged and scrapped; like putting auto oil in the gas.
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MPrimeaux

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Sure there is a kill switch. Here is a pair of mine;

61IMKpdiL2L._SX425_.jpg


Clip one end on the magneto stud and let it hang. When it's time to shut the motor down, touch the other end to ground.

Caution - Do not touch the bare clip to any body part while the motor is turning, either cranking or running. The result is shocking!

Lol....man that made my day!!! I'm at work right now in the shop with a couple other guys and we all got a good laugh out of that. Current routers..... can't call them jumpers anymore.... the adults frown upon jumping stuff out nowadays.. Good stuff. Thanks again man. I really appreciate the help.
 

GA_Boater

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I call mine a Kill Switch. My current router is a Netgear N600. LOL

That statement is overly cautious, I guess to protect Mercury. But running with no battery or even a dead battery, can blow the rectifier. If you pull one of the yellow stator leads, both won't hurt, from the rectifier and don't hook up a battery, the rectifier is safe from blowing.
 

MPrimeaux

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Well if you start the motor without a charged battery hooked up you will destroy the rectifier (although it might be done already)

I was wondering about that merc. I read on the ignition wiring diagram that later models came with a wire from the 12+ to the output of the rectifier so the engine could be turned off at any RPM and not cause damage. I'm guessing to keep 12V on the rectifier at all times? Maybe to prevent some sort of field collapse. Guess I'll remove and tape the rectifier leads to be sure??
 

MPrimeaux

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One other question merc, would you happen to know the resistance measurements that I should get from the stator and any other components that I can check to ensure they're not already damaged?
 

GA_Boater

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I wouldn't worry about the charging system right now. See if the motor will run first cuz no sense spending dough until you know it runs.

My overly cautious thing above was about Mercury saying to disconnect the rectifier wires completely. With no input from the yellow stator wires and no battery, the rectifier is isolated and safe.

I don't understand the extra wire from 12 volts to the rectifier. With a battery connected, the output of the rectifier is to the battery. That's how it charges the battery, it's already there.
 

JPO 1949

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Sure there is a kill switch. Here is a pair of mine;

61IMKpdiL2L._SX425_.jpg


Clip one end on the magneto stud and let it hang. When it's time to shut the motor down, touch the other end to ground.

Caution - Do not touch the bare clip to any body part while the motor is turning, either cranking or running. The result is shocking!

Many many years ago my Mark 58a wasn`t firing so I removed the magneto to clean or replace the points. The points looked good so I cleaned them and replaced the condenser. Put the mag back together and was wiping it down and for some unknown reason gave the splinted shaft a good spin . What a shocking surprise, the mag was lying in my other hand with the bolt down.Lesson I will never forget but I still love these old Mercs.
 

MPrimeaux

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Many many years ago my Mark 58a wasn`t firing so I removed the magneto to clean or replace the points. The points looked good so I cleaned them and replaced the condenser. Put the mag back together and was wiping it down and for some unknown reason gave the splinted shaft a good spin . What a shocking surprise, the mag was lying in my other hand with the bolt down.Lesson I will never forget but I still love these old Mercs.

Ha... well..... at least you fixed it..
 

MPrimeaux

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I call mine a Kill Switch. My current router is a Netgear N600. LOL

That statement is overly cautious, I guess to protect Mercury. But running with no battery or even a dead battery, can blow the rectifier. If you pull one of the yellow stator leads, both won't hurt, from the rectifier and don't hook up a battery, the rectifier is safe from blowing.

Roger that. Better safe than sorry huh? Thanks for the help. I go home tomorrow and I’m supposed to go look at at least one of the motors Tuesday.
 

MPrimeaux

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Ok all, I’ve got a question. I found a 1960? Merc 400. Price is pretty good and comes with all controls. Seller says the motor was dug out of a late grandfathers shed and hasn’t been ran in probably 30 years or better. It’s not quite the hp that I was wanting, but I’m actually second guessing myself on the 650 simply being too big for a boat this size. I want it quick, but I don’t have a death wish. Anyways, I’ve found the 650 w/controls that I mentioned in previous post for $400. I can get this one w/controls for $300. IF compression is ok on the 400, would you rather have one of these merc models that hasn’t been ran in 30 years or one that HAS ran recently, but not now? Thought process is age over hours. Any coaching?
 

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racerone

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Those are a sweet running motor if in good condition.-----If you buy it you will need to evaluate everything before spending more $ coins on it.----60 year old motors need tender care and inspection of everything !!!
 

MPrimeaux

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Those are a sweet running motor if in good condition.-----If you buy it you will need to evaluate everything before spending more $ coins on it.----60 year old motors need tender care and inspection of everything !!!

I was afraid that was the answer racer.... My predicament is that with any of these that would mean me telling the seller, "hey bud. I'm gonna take this motor for a few days and tear it apart. I'll let you know if I want it afterwards." I know it's a gamble with a motor of this age and I understand that sh*% happens, but the chances of me finding a pristine 1960's model mercury is slim. So I'm trying to figure out what my best route is. So maybe I'll ask a different question and go about it differently. Can any of you pro's tell me a part or system that just can't be found or repaired. Is there something that is an absolute deal breaker? Can you still get rings and pistons for them? I THINK that I've found there are some parts in the ignition that are just simply no longer available, but if I understand right they are fairly simple, well made, and TYPICALLY do not go bad. If YOU were going to buy one of these engines to redo, what would you look for and what would make you run for the hills?...Keeping in mind that I am not going to be able to disassemble these engines prior to purchasing. I know I have asked a lot of ya'll and I've spent a good deal of time in the forums since joining. I have noticed that there are a few of you that consistently take the brunt of these questions and I appreciate the time that you all spend trying to help newbies like me. However... I would like to add that I'm not typically one of those guys that ask a bunch of questions and don't follow through. I have kind of an addictive personality and when I do something, I do it all the way. I REALLY want to do this project.... You can convince me that I'm in over my head and it just can't be consistently done and I may just cut the boat up and put a jet ski motor in it (The original plan). Or I may just go a different route on a boat this cool and put a later model reliable outboard on it, but I AM really taking notes and appreciate every bit of mentoring that I've received.
 

racerone

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I think you can find all the parts you need for these.------You have to be patient to get the parts.------You can not get the parts overnight from AMAZON if you are used to that concept.-----I have every part you might need for it and maybe 3 times over too !!
 
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