Re: Johnson 1988 impeller trouble
Water pump service:
1. remove prop
2. disconnect shift linkage under the bottom carb.
3. remove the trim tab (scribe a mark across the edge so you can get it back like it was).
4. remove the retaining bolt up in the trim tab cavity.
5. remove the other retaining bolt from the bottom side of the antiventilation plate.
6. remove the four retaining bolts from the perimeter, just above the antiventilation plate.
7. pull the lower unit off.
the shift rod height is adjusted by screwing it in or out, so don't twist it or else it won't fit when you put it back.
8. Two hex-head screws hold the water tube guide to the pump housing...there's a rubber grommet needs replacing, inside the guide.
9. Four hex-head screws hold the water pump housing down.
10. Slide the old impeller off the drive shaft.
11. Slide the new one on. Slip the woodruff key in place just before the impeller covers the keyway.
12. Put a new housing gasket in place.
13. Grease the inside of the housing (trailer axle grease is fine), and shove it down onto the impeller while turning the driveshaft clockwise with your hand. Don't use any kind of tool on the driveshaft splines.
14. Fasten the housing back on.
On reassembly:
* put molly lube on the drive shaft splines (but not on top, there's not enough clearance).
* the rubber o-ring just below the drive shaft splines -- you need that.
* put omc gasket sealant (or some kind of anti-sieze) on the retaining bolts -- or else corrosion will set in & it'll be a ***** next time.
* use 3m #847 or permatex #2 on the joint between midsection & lower unit.
www.ishopmarine.com has 847 -- permatex is way harder to clean off there next time around. Some guys just leave it bare, it doesn't have to hold water.
