CarMech1969
Regular Contributor
Well boys - looks like my 1988 Johnson 90 just ate a piston.
Funny thing was it acted up for a bit on the lake, and then ran normal again.
Anyhow, I decided to pull the spark plugs, and discovered that all were at about 0.035 except for what I believe is cyl #4 (port side lower). It was at less than 0.020.
I checked for rod play using a dowel and there was none. So I thought it must have sucked in a washer or something, and decided to pull the port head.
Yep, edge of the port side lower piston has come apart, and the glorious little dents all over on the inside of the cylinder head.
It still had good compression despite all this (120 PSI on all, except for the damaged one which has 115) so now I am rather actually thankful that my old Johnny got me home instead of leaving me stranded. Still started and ran perfect when I flushed it out on muffs yesterday evening.
Was wondering how feasible it would be to try and slap another piston in there and call it fixed.
Any comments or advice on this matter is welcome.
Thanks for reading!
CarMech1969
Funny thing was it acted up for a bit on the lake, and then ran normal again.
Anyhow, I decided to pull the spark plugs, and discovered that all were at about 0.035 except for what I believe is cyl #4 (port side lower). It was at less than 0.020.
I checked for rod play using a dowel and there was none. So I thought it must have sucked in a washer or something, and decided to pull the port head.
Yep, edge of the port side lower piston has come apart, and the glorious little dents all over on the inside of the cylinder head.
It still had good compression despite all this (120 PSI on all, except for the damaged one which has 115) so now I am rather actually thankful that my old Johnny got me home instead of leaving me stranded. Still started and ran perfect when I flushed it out on muffs yesterday evening.
Was wondering how feasible it would be to try and slap another piston in there and call it fixed.
Any comments or advice on this matter is welcome.
Thanks for reading!
CarMech1969