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Are the 2T 20 HP Yamaha outboards worth fixing up??

N

Nucad

Regular Contributor
Just wondering what the opinion is on the 20 HP Yamaha two strokes? I have a neglected one from about the year 2000. It was apparently run with a bad impeller and then put away a few years ago. It's free so for fun I'd like to dig around inside. Haven't tested compression yet.
I also have a 1971 Evinrude Fastwin 18 powering my tin boat, but I'd be curious to know how this stacks up? It is certainly heavier. If the compression is good, are parts easily available? And priced like Evinrude parts? So far I seem to be able to find everything I need for the Fastwin.
Opinions by Yamaha experts greatly appreciated.
 
It's a good engine, but all depends on whether or not there was any damage from the overheat. Compression should be around 100psi and same on both cylinders, if it's good then a fuel system clean, water pump rebuild and a good service should see it back on the water.
 
iang6766 said:
It's a good engine, but all depends on whether or not there was any damage from the overheat. Compression should be around 100psi and same on both cylinders, if it's good then a fuel system clean, water pump rebuild and a good service should see it back on the water.
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Sounds good, will do a compression check and go from there..
 
Pulled the head and the top cylinder is heavily scored. Put out about 70 pounds of compression. The lower was about 100. I guess it is toast. I did find a 1992 20 HP power head on CL for $100 claiming to be perfect. Are all the Yamaha 20 HP the same block and pistons?
 
Nucad said:
Pulled the head and the top cylinder is heavily scored. Put out about 70 pounds of compression. The lower was about 100. I guess it is toast. I did find a 1992 20 HP power head on CL for $100 claiming to be perfect. Are all the Yamaha 20 HP the same block and pistons?
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SInce the rest of my engine appears to be in nice condition, just wondering if it is practical to rebore the cylinders and fit oversize pistons? I'm guessing this could be done for a few hundred dollars in parts and machining?
Pricing a 20 HP motor, I'm certainly not going down the new road. Might be a fun winter project too.
 
If you can provide the skilled labour then rebuilding is the best $ option.-----If you have to find and pay a shop it is not worth it.
 
Scoring is NOT normal.-----Pistons will likely show more damage on the skirt.-------If you do not have to WORK for money than you do not have to take care of stuff.----Just get a new one when something goes wrong.
 
anyone know the best source of parts for yamaha motors? They don't seem to be as supported as an old Evinrude.
 
Perhaps the start of -----" you must throw it away and buy a new one " mind set.-----I am going over a 1963 18 HP Johnson right now.-----Lots of used parts are available for those if you know where to look.
 
racerone said:
Perhaps the start of -----" you must throw it away and buy a new one " mind set.-----I am going over a 1963 18 HP Johnson right now.-----Lots of used parts are available for those if you know where to look.
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I have a fasttwin too. Not currently running right, but at full throttle it just flies
 
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