All,
I recently purchased an aluminum boat with a 1972 Johnson 25 hp motor - model# 25EL72R. I thought I was getting a good deal for several reasons, spending less than $500 for boat/motor/trailer.
The seller was a pawn shop and knew nothing about the motor, so I went into this project assuming that the motor had been sitting for quite a while. At first I bought a new gas tank, and fuel line. I attempted to start the motor and it started and ran for a few seconds. I did not want to run it longer because it was not hooked up to cooling water. I then took the boat to the boat ramp to try to take it for a test ride and the motor would not start. Long story short, the fuel pump had given out and that started a long list of repair and replacement of parts. To date I have rebuilt the fuel pump and carburetor; replaced fuel line/tank; replaced the plugs, plug wires, coils, points and condensers. Bad news, the motor still won't idle.
I rent a compression tester (like I should have done in the first place, I know) and the compression in both cylinders is 60psi. I squirt some oil into the cylinders and the compression goes up to 75psi. I am assuming now that it has bad rings.
After removing the cylinder head and the bypass cover I see that the rings are not fused to the piston and the cylinder walls show no sings of scoring. Also, the cylinder head and gasket look fine. My question now is should I break into this engine and replace the piston rings?
Taking the motor as 1/3 of the sale price of the boat and considering all of the ultra-cheap-sourced parts I've replaced, I currently have about $365 in the motor. I think that I could get away with just replacing the piston rings, head gasket, intake gasket, bypass gasket, top and bottom crank seal and the oil/vacuum lines spending only about $100 plus all of my time and labor.
It seems good to me because good used 25 hp motors are running in the $800-1000 range, which is out of my range. Are there any surprise costs I will definitely incur when breaking down this engine? Are there any other parts I should absolutely replace or just ones that show excess wear?
If it's not obvious; money, time and passion are three good things to have and 2 out of 3 ain't bad. Thank you for reading my post.
I recently purchased an aluminum boat with a 1972 Johnson 25 hp motor - model# 25EL72R. I thought I was getting a good deal for several reasons, spending less than $500 for boat/motor/trailer.
The seller was a pawn shop and knew nothing about the motor, so I went into this project assuming that the motor had been sitting for quite a while. At first I bought a new gas tank, and fuel line. I attempted to start the motor and it started and ran for a few seconds. I did not want to run it longer because it was not hooked up to cooling water. I then took the boat to the boat ramp to try to take it for a test ride and the motor would not start. Long story short, the fuel pump had given out and that started a long list of repair and replacement of parts. To date I have rebuilt the fuel pump and carburetor; replaced fuel line/tank; replaced the plugs, plug wires, coils, points and condensers. Bad news, the motor still won't idle.
I rent a compression tester (like I should have done in the first place, I know) and the compression in both cylinders is 60psi. I squirt some oil into the cylinders and the compression goes up to 75psi. I am assuming now that it has bad rings.
After removing the cylinder head and the bypass cover I see that the rings are not fused to the piston and the cylinder walls show no sings of scoring. Also, the cylinder head and gasket look fine. My question now is should I break into this engine and replace the piston rings?
Taking the motor as 1/3 of the sale price of the boat and considering all of the ultra-cheap-sourced parts I've replaced, I currently have about $365 in the motor. I think that I could get away with just replacing the piston rings, head gasket, intake gasket, bypass gasket, top and bottom crank seal and the oil/vacuum lines spending only about $100 plus all of my time and labor.
It seems good to me because good used 25 hp motors are running in the $800-1000 range, which is out of my range. Are there any surprise costs I will definitely incur when breaking down this engine? Are there any other parts I should absolutely replace or just ones that show excess wear?
If it's not obvious; money, time and passion are three good things to have and 2 out of 3 ain't bad. Thank you for reading my post.