What tools needed to check over an old project bass boat before buying?

[dwco5051]

Ok, good to know, I won’t jump it. I can’t find a black with yellow wire on my engine though, could it be a different color? I can post pictures of the engine if that would be helpful.

It has been a long time since I owned an inline Merc and between my 82 year old memory and eyes I don't think I could find it in a picture. The last manuals I still have only go up to 1977. If you could post the serial number on the motor I might be able to point you to the right info. I just assumed that it was the same year as the boat.

 

[Matt129]

It has been a long time since I owned an inline Merc and between my 82 year old memory and eyes I don't think I could find it in a picture. The last manuals I still have only go up to 1977. If you could post the serial number on the motor I might be able to point you to the right info. I just assumed that it was the same year as the boat.

The motor is a 1974 1500 150hp inline 6 with thunderbolt ignition. I couldn’t find the serial number. Also I just saw your profile image, thank you for your service

 

[dwco5051]

The motor is a 1974 1500 150hp inline 6 with thunderbolt ignition. I couldn’t find the serial number. Also I just saw your profile image, thank you for your service

This should be yours; I was thinking of the 1976 850 that shut off by grounding the switch box.

 

[Matt129]

This should be yours; I was thinking of the 1976 850 that shut off by grounding the switch box.View attachment 358979

Looking at the diagram, all of the wires seem to be right except for the black wire coming off of the tachometer connector being cut. Could this be my issue? I don’t see how the tachometer connector could be causing this but I could be wrong lol. Also the mercury switch is missing on my motor completely and I can’t locate the rectifier lol.

 

[dwco5051]

Looking at the diagram, all of the wires seem to be right except for the black wire coming off of the tachometer connector being cut. Could this be my issue? I don’t see how the tachometer connector could be causing this but I could be wrong lol. Also the mercury switch is missing on my motor completely and I can’t locate the rectifier lol.

Here is the page on how your system works. The factory manual does not tell how to test the system without having their analyzer so you have to go by the CDI instructions.

 

[Matt129]

Here is the page on how your system works. The factory manual does not tell how to test the system without having their analyzer so you have to go by the CDI instructions.View attachment 358999

She Lives!!! I started messing around with the stator wires that were very corroded but after I messed with them and she fired right up and she runs dang smooth lol. I think the water pump impeller is out though, but that’s no biggie. Thanks for all of your help!

 

[Erseverkontr]

There is a good chance the seller will not allow you to drill into their boat before purchasing it. Open hatches and compartments are all that's required for this eyesight test. If you haven't already, check out the boat-buying sticky on this page.

 

[Scott Danforth]

She Lives!!! I started messing around with the stator wires that were very corroded but after I messed with them and she fired right up and she runs dang smooth lol. I think the water pump impeller is out though, but that’s no biggie. Thanks for all of your help!

bad wiring is common on old mercs.

suggest you get the wiring replaced, and make sure that all the carbs are gone thru. if you run lean, you destroy the motor

 

[Matt129]

suggest you get the wiring replaced, and make sure that all the carbs are gone thru. if you run lean, you destroy the motor

Speaking of wiring, I had to jump the red and white wires on the switch box to get spark. What in the key switch is probably causing this? The switch still cranks the engine over.

 

[briangcc]

IF you have wonky wiring already, best guess is....who the heck knows. You're asking about a boat that's almost 50 years old and probably had a few owners. **You're looking at a boat that's been "Bubba'd". As in...."Bubba, I got this, hold my beer!"

Replace the wiring as mentioned above, it will more than likely sort out the some/all of the wiring issues. Switches are cheap, I'd replace those too.

 

[nola mike]

Speaking of wiring, I had to jump the red and white wires on the switch box to get spark. What in the key switch is probably causing this? The switch still cranks the engine over.

That makes more sense why it wouldn't start then any of the stator wiring. All you need is power to the yellow wire to get it to crank. The ignition circuit is separate on the white wire. The key switch should connect the white and red wires for the ignition circuit. So it sounds like you need to check terminals in the ignition switch, as well as the connections on the white wire.