I have a 1993 90hp johnson v4 motor I need to order a piston i am trying to figure out if it has been bored out. there is a 030 written on the piston does this meen it is .030 over?
Thanks for the info I found it in the johnson catalog but it says it is for a 1985 johnson 115 hp I guess it does not matter and I should just order the same part number that is in there?
That depends on the cylinder condition. If needed added dia, you are at the end of the journey unless you manage to find a 040 oversize.. Do not order until your machine shop has had a look at it!!
The cylinder walls dont look bad i was going to hone them and they should be good. you cant catch a finger nail on it or anything
I also looked up the part numbers the 0393328 is for a 1985 115 hp .30 over and the part number for the motor that I have is a 0396588 for a 1993 90 hp .30 over and it does not look like they cross does anyone know why?
Thanks for the info I found it in the johnson catalog but it says it is for a 1985 johnson 115 hp I guess it does not matter and I should just order the same part number that is in there?
The supercession chain is 0393328 to 0396588 to 5006669. This means they are interchange. Unless your supplier has really old inventory, you will likely end up with 5006669, the most current part number.
BTW is the piston in the picture the actual one that you will be replacing? I just dont want you to assume they are all the same, somtimes not all cylinders are bored during a rebuild or repair.
Looks like the pictured piston crown is starting to pit/delaminate. Some of the sharp edges on the piston are starting to round off. That cyl may be running lean or may be running hot.
no thats not the piston I am going to be replacing but good point about not assuming they are all the same size. I am going to measure them and make sure I was just trying to see if they are interchangeable. thanks for the info.
