j_k_bisson
Lieutenant Junior Grade
- Joined
- Oct 6, 2010
- Messages
- 1,082
Tried to continue in the original build thread to carry on the discussion of jetting this monster. There have been some performance issues that I was hoping to clear up. But before we get into the nitty gritty, I thought I would give a basic overview.
The motor was built in thread; http://forums.iboats.com/showthread.php?t=457212 The skinny is that the motor is a 1986 Johnson 200hp mid and lower unit. The block and rotating assembly is a 1990 Evinrude/Johnson 225hp. The ingition system is a 1987 Evinrude 200/225hp. The carberators are the wild card, no idea what year they are from. They are from year 1986 thru 1990 200 to 225hp Evinrude/Johnson.
The main issues I am having with the motor is at mid range 12-18mph in the boat in rough water the motor does not maintain speed. It either slowly increases speed untill it gets up on plane, or looses speed. While this is going on the motor is kicking like it is loading. Also the load speed hole shot is bogging.
Now to understand the motor have been installed and adjusted on the boat for motor height. That has been set to the most efficient height. The boat is a 1991 Bayliner Trophy 2002 walkaround. The boat I feal is not too heavy for this motor. I have adjusted the prop down to 15" x 15"P from a 14.3"x23"P. The motor ran great after I got it up to speed with the higher pitch prop. But getting there took for ever. The motor bogged completely with the higher pitch props.
Now the reason for this thread. I have been really investigating the carbs seeing they are the wild card here. I believe that the carbs are not properly jeted for the best prop I could be using. I want to increase the pitch of the prop to a 14.5" x 17"P prop. I was running this prop earlier in the last year season. I had to drop the pitch due to the motor really kicking at mid range speeds. The motor would really load with fuel. It would not stall but the plugs would carbon up allot. If the motor was shut down at this point, the plugs where drenched.
So I was thinking after the following investigation;
1986-87-88 225hp Evinrude had different jetting each year. The jet stayed the same between the years 1988 thru 1990. In 1990 the carbs changed along with the jetting. Also the part number for the carb bodies are the same for all these years 1986 thru 1990. Also the the carb rebuild kits are the same for the same years 1986 thru 1990.
So my thinking was I was going to change out my jets with my current prop and see what happens in the mid range. For the price of jets I was willing to play a bit.
Here is what I was thinking....
Current;
1987 Main; 62d, Mids; 14, Idle; 48
Proposed;
1988-90 Main; 62d, Mids; 47, Idle; 34
Now the questions;
1) Does anyone have or had a 1988 thru 1990 Evinrude/Johnson mounted on a 2300lb walkaround boat and what prop and performance characteristics do they experience?
2) What are everyones thoughts about swapping jets from year to year?
3) Are there any diffrences between the bodies/bore diameters on the carbs between 1986 thru 1990?
4) What are the risks on swapping the jetting thinking of lean idle and rich mids to the opposite?
5) Anyone ever thry this?
Let the disscussions begin..........
The motor was built in thread; http://forums.iboats.com/showthread.php?t=457212 The skinny is that the motor is a 1986 Johnson 200hp mid and lower unit. The block and rotating assembly is a 1990 Evinrude/Johnson 225hp. The ingition system is a 1987 Evinrude 200/225hp. The carberators are the wild card, no idea what year they are from. They are from year 1986 thru 1990 200 to 225hp Evinrude/Johnson.
The main issues I am having with the motor is at mid range 12-18mph in the boat in rough water the motor does not maintain speed. It either slowly increases speed untill it gets up on plane, or looses speed. While this is going on the motor is kicking like it is loading. Also the load speed hole shot is bogging.
Now to understand the motor have been installed and adjusted on the boat for motor height. That has been set to the most efficient height. The boat is a 1991 Bayliner Trophy 2002 walkaround. The boat I feal is not too heavy for this motor. I have adjusted the prop down to 15" x 15"P from a 14.3"x23"P. The motor ran great after I got it up to speed with the higher pitch prop. But getting there took for ever. The motor bogged completely with the higher pitch props.
Now the reason for this thread. I have been really investigating the carbs seeing they are the wild card here. I believe that the carbs are not properly jeted for the best prop I could be using. I want to increase the pitch of the prop to a 14.5" x 17"P prop. I was running this prop earlier in the last year season. I had to drop the pitch due to the motor really kicking at mid range speeds. The motor would really load with fuel. It would not stall but the plugs would carbon up allot. If the motor was shut down at this point, the plugs where drenched.
So I was thinking after the following investigation;
1986-87-88 225hp Evinrude had different jetting each year. The jet stayed the same between the years 1988 thru 1990. In 1990 the carbs changed along with the jetting. Also the part number for the carb bodies are the same for all these years 1986 thru 1990. Also the the carb rebuild kits are the same for the same years 1986 thru 1990.
So my thinking was I was going to change out my jets with my current prop and see what happens in the mid range. For the price of jets I was willing to play a bit.
Here is what I was thinking....
Current;
1987 Main; 62d, Mids; 14, Idle; 48
Proposed;
1988-90 Main; 62d, Mids; 47, Idle; 34
Now the questions;
1) Does anyone have or had a 1988 thru 1990 Evinrude/Johnson mounted on a 2300lb walkaround boat and what prop and performance characteristics do they experience?
2) What are everyones thoughts about swapping jets from year to year?
3) Are there any diffrences between the bodies/bore diameters on the carbs between 1986 thru 1990?
4) What are the risks on swapping the jetting thinking of lean idle and rich mids to the opposite?
5) Anyone ever thry this?
Let the disscussions begin..........
