1967 Super Seahorse 80

[Eddie0]

I have a boat with 1967 Super Seahose 80 Model # V4SL19R which sat in a garage for 5 years. I took it out and had the motor tuned up and went to the lake. It started great and ran fine for about 15 minutes and then began to loose power and miss a little. When I took it back to the shop, they kept it about a week, checking compression and the head gaskets. They finally said that it runs fine for a while and then it looses compression. They think it may be internal. Has anyone experienced this before?

Also where can I get a repair manual.

Eddie0

 

[Willyclay]

Re: 1967 Super Seahorse 80

Welcome to the iboats.com forum. The experts here, which I am not, can answer any question about your boat, motor and trailer. I believe this forum is the single best resource for recreational boaters. I had a 1962 Johnson 75 which is almost identical to your motor but never had a similar experience. Can you check the compression yourself, cold and warm, and post the results? Reprints of the OMC factory service manual are available from kencook.com and aftermarket versions are available here at the iboats store. Good luck?

 

[1946Zephyr]

Re: 1967 Super Seahorse 80

Sounds like a reed box problem to me

 

[F_R]

Re: 1967 Super Seahorse 80

Eddie, I don't know what is wrong with your motor, but I sort of doubt the diagnosis. I suppose it could have some stuck rings, but it seems like they should stay stuck, not come and go.

 

[Eddie0]

Re: 1967 Super Seahorse 80

Thanks Zephyr,

What is a reed box?

 

[Eddie0]

Re: 1967 Super Seahorse 80

Eddie, I don't know what is wrong with your motor, but I sort of doubt the diagnosis. I suppose it could have some stuck rings, but it seems like they should stay stuck, not come and go.

According to the mechanic they checked the rings.

 

[Eddie0]

Re: 1967 Super Seahorse 80

Welcome to the iboats.com forum. The experts here, which I am not, can answer any question about your boat, motor and trailer. I believe this forum is the single best resource for recreational boaters. I had a 1962 Johnson 75 which is almost identical to your motor but never had a similar experience. Can you check the compression yourself, cold and warm, and post the results? Reprints of the OMC factory service manual are available from kencook.com and aftermarket versions are available here at the iboats store. Good luck?

Thanks Willyclay,

I will double check the compression and post it.

 

[steelespike]

Re: 1967 Super Seahorse 80

Reeds perform something like the valves in your car.They let the fuel air mix into the crankcase then seal so pressure builds in the crankcase to help force the mix into the cumbustion chamber.
Sometimes as old coil(s) heat up they get weak.Many times a motor that sat for a long time will develope fuel system problems unless the fuel system is gone through before puting it back into service.When it starts to fade
see if it responds to a little choke.Also see if squeezing the primer bulb helps.
I would think a good shop would check all these things.
In my mind losing compression in those circumstances is highly unlikely.
Are you sure it isn't overheating?That can cause it to fade.

 

[Willyclay]

Re: 1967 Super Seahorse 80

Trying to send you a Private Message and need to know if your forum name is Eddie with a "zero" or the letter "O"? Looks like there is one of each in the membership list. Thanks!

 

[Eddie0]

Re: 1967 Super Seahorse 80

Trying to send you a Private Message and need to know if your forum name is Eddie with a "zero" or the letter "O"? Looks like there is one of each in the membership list. Thanks!

It's Eddie with a "zero"

 

[Willyclay]

Re: 1967 Super Seahorse 80

Thanks, PM just sent.

 

[perkdp]

Re: 1967 Super Seahorse 80

seems like the rings would expand and increase compression as it warms up.

surely the shop checked coils & spark as it started to fade.

loose head bolt(s) allowing the head to expand and allow compression seepage after it warms up ?

 

[Eddie0]

Re: 1967 Super Seahorse 80

Reeds perform something like the valves in your car.They let the fuel air mix into the crankcase then seal so pressure builds in the crankcase to help force the mix into the cumbustion chamber.
Sometimes as old coil(s) heat up they get weak.Many times a motor that sat for a long time will develope fuel system problems unless the fuel system is gone through before puting it back into service.When it starts to fade
see if it responds to a little choke.Also see if squeezing the primer bulb helps.
I would think a good shop would check all these things.
In my mind losing compression in those circumstances is highly unlikely.
Are you sure it isn't overheating?That can cause it to fade.

Thanks Steelespike,

I know he replaced the distributor cap because I had to wait for him to order it but I don't know about the coil.