1993 Johnson Evinrude "ET" 90 degrees CV Service Manual, P/N 508285, Page 343Get this manual
4931Remove the high pressure port O-ring 5032Remove the trim-down relief valve and springrs1l33Clean and inspect the components of the trim-down pump relief valveReplace the rubber sealif necessaryThe seal can be easily removed from the valve with your fingernailPress new seal in place with the ridge facing out5 134Remove the spring from the expansion relief valve
53 135Remove the expansion relief valve core5436Remove the expansion relief valve seat55137Clean and inspect all the components of the expansion