1983 Johnson 115 hp not coming up to full power

[DeepCMark58A]

Had an issue last fall with the motor losing power than not running. The boat has a built in tank so I replaced the fuel filter, the fuel pump and fuel filter. The motor would not start. I suspected an issue with the fuel pick up so I went and bought a 6 gallon can and plumbed that in the motor starts and runs. I put the boat in the water and the cold start is better, the low idle is better. When I put the boat the to full throttle it not not stumble at all it is running about 1500 rpm lower than what it ran in the past. Not sure what the issue is.

 

[racerone]

You must know that these V-4 crossflow engines are famous for broken rings.---Post the compression numbers.---Easy and no beer tokens needed to do that.----And make sure there is strong spark ( 3/8" gap ) on the 4 leads.

 

[DeepCMark58A]

You must know that these V-4 crossflow engines are famous for broken rings.---Post the compression numbers.---Easy and no beer tokens needed to do that.----And make sure there is strong spark ( 3/8" gap ) on the 4 leads.

Yeah I have begun looking for the compression tester, have not seen it since the move.

 

[DeepCMark58A]

Went into town to see if the hardware store had a compression tester, no luck. How ever the owner went in the back and got his personal to let me use. There is a reason you pay extra and shop locally.

 

[DeepCMark58A]

Well did not really need a compression tester, pulled the 4th plug, the electrode was smashed flat. Question is a 1983 Johnson worth rebuilding? Or have rebuilt I should say.

 

[racerone]

Take head off and have a look.------Some folks can not / will not accept that these are fine motors and worth rebuilding.-----Many shops no longer work on these simple motors.-----And having a shop as your servant can be expensive.----Your decision.----A new 115 HP technical marvel might set you back $12,000 beer tokens or more.

 

[DeepCMark58A]

Take head off and have a look.------Some folks can not / will not accept that these are fine motors and worth rebuilding.-----Many shops no longer work on these simple motors.-----And having a shop as your servant can be expensive.----Your decision.----A new 115 HP technical marvel might set you back $12,000 beer tokens or more.

Thing are a little different in rural MN lots of shade tree mechanics. I would prefer to have it rebuilt I love the smell of 2 stroke in the morning.

 

[racerone]

Every town used to have someone who could do that work.-----If it was the only motor I had it would be rebuilt " in house " ---- boring , honing and fine fitting is simple to me.

 

[DeepCMark58A]

Every town used to have someone who could do that work.-----If it was the only motor I had it would be rebuilt " in house " ---- boring , honing and fine fitting is simple to me.

The odds of me learning how and doing it right on the first try are pretty small, I prefer to pay the people that know what they are doing to do it right, well worth the $. The boat and motor are 1983 what would have been a corvette to me when the boat was built when I was 17 it would have been a dream to me, to me it is worth getting rebuilt if possible.

 

[racerone]

Ask around your local boating community.---Or buy a rebuilt powerhead and install it yourself.----These motors are famous for broken rings.-----Anybody doing this work will have done a few of them !

 

[DeepCMark58A]

Well I am unable to find a willing mechanic, a new powerhead is about $2800. I am stopping to look at a 115hp Mariner tomorrow.

 

[racerone]

No surprise to me that shops are not willing to take this job on.

 

[DeepCMark58A]

No surprise to me that shops are not willing to take this job on.

I was told don't do it for what it costs I will be better off buying another used .

 

[racerone]

There are different opinions out there.------A rebuilt 1983 V-4 is a very good motor.-----You have to know how to start them.-----Uses more fuel than a new 4 stroke.-----Does not require $100/hr shop support.