165 MERC cooling question

[Big Guy]

I own a 1987, 165 HP Merc with four cylinders. Is this the "470"? It runs on the very warm side of the gauge. Too close to the red zone for comfort, but still in the cool zone. This thing has the water cooled voltage regulator as well. I live in Vermont and this boat will never see salt water. Does the means exist to convert the system to full fresh water cooling versus the closed loop system?

 

[Don S]

Re: 165 MERC cooling question

Yes, it's a 470, No, there is no way to convert it to raw water cooling.

Have you replaced the impeller in the outdrive lately?

 

[achris]

Re: 165 MERC cooling question

Or had the heat exchanger cleaned, or check the thermostat, or checked the exhaust elbow for blockage?

 

[Big Guy]

Re: 165 MERC cooling question

When I drained the heat exchanger for winter there was a piece of an impeller vane that came out. This problem existed the entire season last year. but as long as it stayed out of the hot zone I looked the other way.

Is it true that I can convert this over to an alternator system versus the stator system quite easily. Will I need to change out the voltage regulator as well?

 

[Don S]

Re: 165 MERC cooling question

Is it true that I can convert this over to an alternator system versus the stator system quite easily. Will I need to change out the voltage regulator as well?

The conversions aren't really that hard to install, and the regulators are built into the alternaors. The water cooled regulator gets eliminated or at least disconnected and not used. Personally, I would pull the front pulley and remove the stator, that way when (not if) the magnets come loose from the pulley, they don't hang up on the stator and break things. The pulley is NLA, so you would be searching for new one if it got broken.

 

[Big Guy]

Re: 165 MERC cooling question

Okay good to know. My charging system does charge, but not very well at an idle. I expect to have to replace the stator eventually because that seems to be the pattern with those things. I would rather eliminate the issue sooner than later in this case. Thanks for your help.