1963 Super Seahorse 75 Help

[Milksnake12]

Well I need some help! I picked up an old Fiberform that has a '63 Super Seahorse 75 outboard on it. The motor starts and idles fine. I get it into forward gear and start giving it some throttle, I'd say around 10mph it stops accelerating no matter how much more throttle I give it and it makes an occasional thud sound and vibrates pretty bad. Several times around the 10mph mark it lost throttle and the sounded like gears clicking really fast (not a real nasty grinding sound). The prop spins easily and smoothly by hand when out of the water.
I know I'm asking simple questions about a complex motor, but I don't have any experience working on outboards and don't really know where to dive in looking for the issue. Or if it's worth even bothering on this motor.

Anyone have any advice on where I should look for the problem first?

 

[racerone]

Is it the simple electric shift model ?-----Model # is ?

 

[Milksnake12]

Model is a V4SL 12S. Not sure on the electric shift part, it has one cable from the shifter at the helm that pushes a lever back and forth for F/N/R.

 

[racerone]

Manual shift model.----Take the gear box apart for inspection.

 

[oldboat1]

Believe that is a '60 model.

 

[Milksnake12]

Might be a stupid question, but if I grab a barrel to start troubleshooting this, can I give it some throttle while in the barrel?

 

[F_R]

Not much, or it will empty the barrel.

Sounds like the clutch dog and forward gear are slap wore out.

 

[Milksnake12]

I started diving into the gear box and I'm stuck trying to get the shift yoke out.
I'm having trouble finding anything specific for this motor, the closes I found is this YouTube video https://youtu.be/mJBHxKhCUu8?t=529, it's set to the spot where he removed the yoke. His motor had a plate on the side of the lower unit that had a bolt he unscrewed that released the yoke. My motor does not have that and can seem to get the yoke out.
Anyone have any insight on getting the yoke out of this motor?

 

[racerone]

There is no point in looking at that video.!!-----It is a totally different set-up to yours.----Waste of time that.

 

[Milksnake12]

It was the closest thing I could find. I can't turn up anything useful on the web.

 

[racerone]

There are a number of places where you can look up the parts bits.------evinrudeparts.ca----Is one of them.-------Now a 1968 model 85 HP mechanical shift has the same gearcase.-------So look at the parts and you should be able to see what has to be done.-----Going to take more than 10 minutes to fix this.

 

[oldboat1]

Alternatively: https://www.ebay.com/itm/2-Piece-Lo...=401315226804619f8337d93b42c1bc6dcdec1ab66550 Compare cost to that of replacement parts. (Confirm full operation with seller before purchase.)

 

[Milksnake12]

I'm still struggling trying to get this yoke out. Does anyone know if the lower unit needs to be removed first?

 

[racerone]

Lower unit needs to come off.----Upper and lower half need to be separated.

 

[F_R]

Not endorsing it, but this video shows a bit of what you are in for. Those units can be very difficult, or even impossible to get apart if it has seen salt water.

https://www.youtube.com/watch?v=Z12m5zr0wh0

 

[racerone]

Actually a very good video.----But he called the reverse gear the FORWARD gear.-------Hopefully he had it figured out when it came to installing the clutch dog " good side " on assembly !!