90hp merc buyers checklist

[bcbob]

I'm going to check out a 89 Merc 90hp o/b and wanted to know what I should be looking for. The engine is not on a boat but I will be able to here it run. I'm going to do a compression test on it but I don't know what other items to check. If any one is a veteran at this or has gone through a similar process, your input would highly regarded. Thanks

 

[trevorcday]

Re: 90hp merc buyers checklist

In addition to compression:<br />1. check for spark on all cylinders, <br />2. peek in each spark plug hole looking for any signs of a melted piston crown, <br />3. take out bottom lower unit drain screw and look for water, metal particles and milky oil, <br />4. spin the prop while watching the tip of the prop shaft for runout (should be none visible)<br />5. Make sure that the lower unit gets good engagement in both forward and reverse (especially reverse)<br />I'm sure there's more but that is all that comes to mind right now.

 

[Red De Braal]

Re: 90hp merc buyers checklist

One more thing check the Tilt/Trim - All the way up and all the way down. If you need to replace it BIG BUCKS !! The trim motor should sound smooth and steady.<br />Good Luck Red !!