1984 150 troubles

[gogono2]

I have just acquired a free 1984 Mercury 150 outboard and Im in the process of replacing and rebuilding the obvious. After cleaning and rebuilding the carbs there is fuel leaking foward from the air intakes. Is this normal? Also will a bad "black box module" keep the plug wires for firing? Thanks

 

[j_martin]

Re: 1984 150 troubles

I have just acquired a free 1984 Mercury 150 outboard and Im in the process of replacing and rebuilding the obvious. After cleaning and rebuilding the carbs there is fuel leaking foward from the air intakes. Is this normal? Also will a bad "black box module" keep the plug wires for firing? Thanks

Welcome to the board.

Fuel leaking under what conditions?

Many things will keep the plugs from firing.

I suggest you get your hands on a factory service manual. It has all the detailed information you need.

hope it helps
John

 

[gogono2]

Re: 1984 150 troubles

Thanks for the reply. I do have a manual but dont have any testers to check electronically. I have replaced the stator, plugs, and rectifier. all other wires and connections look normal except for the black box module (dont know the functional name) where a wire is coroded from top to bottom with no insulation. Im hoping a new one will make it fire but was not sure if an inoperable one would keep it from firing.

The fuel leaks out of the air intake when i prime the bulb. Of course none is being consumed during start attempts because there is no spark.

It sat unused for 10 years and was operating fine before that period of time.

Thanks
Shane

 

[j_martin]

Re: 1984 150 troubles

I have no idea what you mean by a black box module? What is it connected to. What color wires are on it? Where is it mounted? Can you find it in the diagrams in the book?

It's likely either a shunt type voltage regulator, or an "advance" module.

John

Thanks for the reply. I do have a manual but dont have any testers to check electronically. I have replaced the stator, plugs, and rectifier. all other wires and connections look normal except for the black box module (dont know the functional name) where a wire is coroded from top to bottom with no insulation. Im hoping a new one will make it fire but was not sure if an inoperable one would keep it from firing.

The fuel leaks out of the air intake when i prime the bulb. Of course none is being consumed during start attempts because there is no spark.

It sat unused for 10 years and was operating fine before that period of time.

Thanks
Shane

 

[gogono2]

Re: 1984 150 troubles

Well, for some reason the manual actually calls it the "black box module" in the bold print but then calls it the idle stablizer. It sits atop the block just below the stator and terminates at the distributor plates. Hope that clarifies a bit.

Thanks
SHane

 

[ufm82]

Re: 1984 150 troubles

If fuel leaks out when you pump the bulb, you may have a float stuck somewhere and the fuel is coming out of the carb bowl, you may have a gasket pinched on a bowl seal, you may have a leaky fitting at a hose on the carb or other leak. Although you said you just rebuilt the carbs, anything can happen. A pin could slide or a gasket could shift or get pinched. You have three carbs I would think?

Strip off as much as possible to gain visibility and pump the bulb. A leak should be pretty evident if you have the thing as naked as possible.

UFM82

 

[gogono2]

Re: 1984 150 troubles

thanks, that helps. although i know my way around a car, Im new to boats motors. When I took the plate off for the first time I saw a good amount of oil and gas and just wondered if this was a result of flooding.

 

[j_martin]

Re: 1984 150 troubles

Well, for some reason the manual actually calls it the "black box module" in the bold print but then calls it the idle stablizer. It sits atop the block just below the stator and terminates at the distributor plates. Hope that clarifies a bit.

Thanks
SHane

You can safely discard that module. It can kill the ignition, and it can also fail in a way that way overadvances the timing, grenading your powerhead. Maybe that's why Murkery discontinued the part number.

If the book calls for initial WOT timing of 19 degrees, set it to 23 degrees without the module.

What it's supposed to do is advance the timing a few degrees if the idle falls below 700 rpm. If the engine is in decent shape and tune, it should idle reasonably without it.

ufm82 is helpin' ya with the carbs.

hope it helps
John

 

[gogono2]

Re: 1984 150 troubles

Thanks, I havent even tried to start it with it disconnected. If it works it will save me about 200 bucks.

Shane