1954 10 johnson rebuild

[gmarshall43]

I have a 1954 10 hp johnson that I'm deciding whether to put new rings in it. It has become hard to start and the compression is about 60psi in each cylinder. I have cleaned the carb and changed out the points but doesn't run like it used to. It was a good running motor and I wonder if it would be worth it to change out the rings and gaskets. What's the opinion on this?

Thanks,
Gary

 

[Crosbyman]

I never went so far as to do rings on an oldy but have you looked into alternatives such as an engine cleaner like Merc POWER TUNE and BRP equivatents, pulled the cyl head to check/confirm excessive wear, checked the rings condition by openning the side bypass covers, ??

 

[racerone]

Does spark jump a gap of at least 1/4" on both leads?----Is compression gauge tested and accurate ?----Agreed remove cylinder head for inspection.----Remove bypass covers,---Rings could be stuck.-----Check for play in wristpin bushings.------If going ahead then look into upgrading.------Install pistons and rods from a 1961 / 62 / 63 model.-----Much improved wrist pin bearing .-----Then again maybe that was done already.

 

[909]

If you value your time ... IMO it's not worth it since you can get a modern 9.9 for very little money, which is has higher compression, better fuel efficiency, more power & speed and is arguably more reliable.

 

[racerone]

But if you remember fishing trips with grandpa and this motor , then keeping it in the family is " PRICELESS '-----Some decisions are not based on beer tokens alone.

 

[racerone]

Once you inspect a 1954 model 10 HP and overhaul it properly it will be a cheap motor to own.-----No expensive " fail suddenly " parts on it.-----New impeller every 10 years and gear oil once in a while !

 

[Crosbyman]

best of both worlds 2 sets of points, 2 condensers, 2 coils 2 plugs

 

[racerone]

These older motors " warn " you when it time to clean the points.----And the DUAL ignition system will allow it to run on one cylinder.----It has 2 seperate ignitions , one for each cylinder.

 

[gmarshall43]

thanks for all your inputs. I remember when it ran well, it would keep up with the newer motors. I think it will make a nice winter project

 

[Roberthill]

Sometimes just changing spark plugs is all it takes , fuel bad maybe , several things to consider . Good suggestions already posted . Results ???

 

[Crosbyman]

this series of a refurbish of a 15hp is a good guide .... same basic issues

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