Impeller Base Plate Leak

This is a 1989 6 HP 2 stroke. Thought I had a seal leak in lower unit. Did pressure test and the leak appears to be a gasket under the plate that the the impeller housing bolts to. All the bolts are out. Gently tried prying this up and it doesnt seem to want to budge. Don't want to damage it so I need help. Will it eventually pop loose with enough pressure? Is the seal what is holding it in place? Special procedure? Sorry. Still new to outboards. Pic below. Thanks for the help.

Get a sharp knife with a thin blade that you no longer have use for. Lay the sharp edge along one of the narrow edges, where the gasket is. Now tap the back of the blade so that it goes into the gasket, you only need to go in 1/4 inch. Remove the blade and proceed to do the same thing around the rest of edge. The shifter will also come out as you remove the plate. the plate has a thin wall in the water pump area on the bottom side. If it is badly corroded-- replace it. There are also two seals in the plate, just below the area that the drive shaft goes through. They are easy to replace, and you probably won't require the bushing. It is already in the plate if you needed it.

Yeah strong possibility it's already corroded out on the underside and that's why it's leaking. Probabably needs to be replaced anyway. It's about $50 at Boats.net or a little more at your local Yamaha dealer.

-Mike







http://www.boats.net/parts/search/Yamaha/Outboard/1989/6SF/LOWER%20DRIVE%201/parts.html

Update: I did get base removed. Actually, it is in really good condition. The gasket just blew a hole. Got everything cleaned up, replaced seals and getting to reassemble. One question though. The shift lever did come out just as mentioned. I noticed at the end, there are a couple of notches, I'm guessing each notch represents a gear, forward, reverse, neutral. I had to shift into first gear to get lower unit to drop loose from motor. Now, I am confused as to how far I should push shift lever back into position. I'm trying to avoid problems when I go to reattach lower unit. In other words, if I settle it into first notch, what gear am I in? Will it let me push it further than that? Does it matter? Hoping to reassemble tomorrow. Any help here greatly appreciated. Oh, and how much grease should I apply to spline when I go to reassemble? I know...more than one question. lol I just don't want to tear this down again by making a dumb mistake.