1984 Mercury 150 Black Max ,smoke & little water threw pump

Dodger1

Recruit
Joined
Dec 5, 2009
Messages
4
Just bought and had it started, but only had the ears on it, it pumped but
It was not like I wanted,does it take more pressure with the ears?and it smoked some?could that be the oil from sitting for couple months?It cranked right up,but had these couple Questions.
 
Last edited:

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Re: 1984 Mercury 150 Black Max ,smoke & little water threw pump

Knowing the engine history would help; possible issues:

1. Bad fuel
2. Varnish in fuel system caused by lack of operation
3. Water pump impeller damaged due to sitting up if that applies
4. Water pump impeller damaged due to usage and being worn out
5. Carbon laden combustion chambers due to lack of cleansing and years of usage.
6. Dirty sparkplugs
----------------

You have to decide what you want to do.

A tank of fresh fuel using Merc's finest 2 cycle engine oil and about 1 16oz can of Sea Foam (at Autozone or others) per 5 gallons (2 for 10 gallons)_of fuel to start and a couple hours of blasting around the lake and your performance and smoking issues should be under control. Then, when you get home, put in a new set of sparkplugs and the next time you are at the lake it should be a piece of cake.

The engine should have thermostats and a thermal overload alarm. If you get into problems during your run-in then stop and go get a water pump repair kit and install it......or better yet, before you make your run, install the kit and be done with it.....best idea.

With those three things accomplished, you should have your problems solved. On the Sea Foam, once you have cleaned out the carbon and crap from your engine, 1 oz per gallon of fuel (fuel oil mix) is the recommended maintenance ratio and the engine likes it. Money well spent .

Balls in your court.

Mark
 

j_martin

Admiral
Joined
Sep 22, 2006
Messages
7,474
Re: 1984 Mercury 150 Black Max ,smoke & little water threw pump

Knowing the engine history would help; possible issues:

1. Bad fuel
2. Varnish in fuel system caused by lack of operation
3. Water pump impeller damaged due to sitting up if that applies
4. Water pump impeller damaged due to usage and being worn out
5. Carbon laden combustion chambers due to lack of cleansing and years of usage.
6. Dirty sparkplugs
----------------

You have to decide what you want to do.

A tank of fresh fuel using Merc's finest 2 cycle engine oil and about 1 16oz can of Sea Foam (at Autozone or others) per 5 gallons (2 for 10 gallons)_of fuel to start and a couple hours of blasting around the lake and your performance and smoking issues should be under control. Then, when you get home, put in a new set of sparkplugs and the next time you are at the lake it should be a piece of cake.

The engine should have thermostats and a thermal overload alarm. If you get into problems during your run-in then stop and go get a water pump repair kit and install it......or better yet, before you make your run, install the kit and be done with it.....best idea.

With those three things accomplished, you should have your problems solved. On the Sea Foam, once you have cleaned out the carbon and crap from your engine, 1 oz per gallon of fuel (fuel oil mix) is the recommended maintenance ratio and the engine likes it. Money well spent .

Balls in your court.

Mark

A water pressure gauge on a V6 merc is indispensable. There is such a hellacious amount of fire in that compact engine that it cannot survive cooling system failure very long. With a pressure gauge, you get used to what it normally does, and go looking for trouble if it isn't right, preventing damage.

They're always smokey on cuffs, and often smokey at idle on the lake. Normal.

hope it helps
John
 

Barnacle_Bill

Admiral
Joined
Feb 8, 2004
Messages
6,469
Re: 1984 Mercury 150 Black Max ,smoke & little water threw pump

I use to have the same motor and fought those 2 problems for a long time. Even tried running synthetic oil. Rebuilt carbs and fuel pump, even tried an electric pump just for testing. It still smoked A new impeller improved the idle water flow a little. I started paying more attention to identical motors and they all did the same thing. I concluded its just the nature of that particular beast. Do all the things Texasmark said and keep on fishing.
 
Top