Black Max 150 maintenance?

[Clyde]

I have a very good running 1989 black max 150 merc on my Pro Craft. I have changed the plugs and lower unit oil. The oil injector has been disconnected for a long time. I have known this boat and engine since it was new. Even though I have only owned it for a little over a year. What sort of maintenance do i need to keep up with. When do the thermostats need to be changed. Just looking for tips to help keep a good engine good. Thanks

[NBR]

I have the same on a1989 Astro which came from the same molds as your Procraft. I do the normal winterize stuff and every second or third year I have the carbs/fuel system gone over and a new water pump impellor installed.

I didn't fish much this year with the first time out in early Sept. Motor ran a bit poor and on the third trip out it shut down and was hard to restart. With the weather starting to get too cold for this old guy I decided to put the rig to bed for the winter. When I took the plugs out the lower on the lowest left side (viewed from the back looking forward) was badly corroded so I hope that the new plugs solve the hard start issue.

I don't like to jump a post but does anyone have a clue to the corroded plug? It was really bad but the others looked fine.

[Clyde]

I have done the water pump also I forgot to add that. I have not done anything to the carbs though.

[Mike 12345]

I have a 91 Black Max 150 on my ProCraft. I change the spark plugs twice a year, and have the water pump (impellar) changed every other year (new lower unit lube necessarily comes with that).

I need to have the carbs cleaned/serviced this winter.

Use Sta-Bil Ethanol treatment in your fuel (or your brand preference).

Other than that, I don't do much. I fish during the winter, so I don't officially "winterize", but since the boat must stay outside, I make sure it is well covered and either trim the motor all the way down or cover the lower unit completely with plastic bags and tie them off so no water gets in the lower unit and freezes in the winter.

Runs like a champ.

[Clyde]

Thanks Mike. Where on old hickory do you fish. I been fishing there about every week end. PM me I always like to talk to other folks fishing the lake.

[GLADES]

I have a 1984 Mercury 150 Black Max. I usually change the impeller annually or when I notice a decrease of water pressure on my WP gauge. The rubber can dry rot. Also, never start the engine without water. It only takes a split second and the impeller is toast. I replace the fuel lines, bulb, and have the carbs cleaned, adjusted, every two years. The lower unit oil, every year. Plugs 2-3 years. A couple of bucks spent each year will prevent poor performance or expensive repairs. Pull the prop off now and then and check for braided line wrapped around the prop shaft. A well maintained Mercury 150 will last for many years. They are one of the best engines ever made IMHO.

[backseatk]

impeller and lower unit oil every year, fuel pump every other, carbs 3yrs or less, plugs-power tune every year