Is This Motor Too Far Gone??

[gayle23]

I have a 1979 Johnson 6 hp outboard which I have owned for about 17 years. Prior to that it was owned by an outfitter and used for commercial uses so it has had a big life. Last fall I did a compression test and found both cylinders had compression of 50 psi. I decided to do a decarb to see if I could increase compression. I poured Seafoam into both cylinders and let it sit over night. In the morning I poured the rest of the Seafoam into about 2 gallons of gas, started the motor and took off. It smoked heavily for a short period of time, then things went well for about one city block. Then the motor started to get slower and slower, even with the throttle turned all the way up. The motor stalled twice before I got back to the dock. The motor barely runs.

I have also had trouble with the fuel pump. I rebuilt it and tested it to make sure it was operating properly (cannot blow into the outflow tube but can blow into the intake tube). Even though it seems the fuel pump should be working properly, I still need to pump the primer bulb periodically. I am thinking the compression is too low to efficiantly operate the fuel pump???

Also, the motor has been recently been jumping out of gear when running.

Anyway, I am seriously thinking of parting out this motor, even though I am very attached to it. A ring job, plus the lower unit problem seems like a lot to take on for a motor of this age.

Please advise.

Thanks.

 

[BonairII]

I'm always suspect when I hear that ALL cylinders are very low.....but perfectly equal. IMHO, the chances that both cylinders wearing out that evenly makes me suspect of the compression gauge rather than the cylinders.

I certainly could be wrong, though. I would check it with another gauge just to be sure. If indeed the readings are correct, then you can pull the head to inspect for cylinder/ring damage.

Jumping out of gear is probably the result of worn shift dogs.

In the end, I'm guessing that parting it out may be your best option. Finding parts for that motor may be difficult and/or expensive.