Engine Overheating or What?

[Royboy]

Hi, I am a real novice when it comes to Outboard engines. I have a 35 HP (although the paper work says it is a 26HP) Mercury. I had it serviced this year and the gent at the Marina suggested I remove the Oil system I had as it was quite old and parts were no longer available. I said ok and now I have to mix my oil with the gas. Not a problem except now I have the warning noise that appears to come from the throttle control area. The guy at the Marina tells me the engine must be over heating and I need to change the lower unit or something. Does this make sense to you pros? Thanks.

 

[funpilot]

Re: Engine Overheating or What?

The warning horn is the overtemp buzzer. It's telling you to reduce throttle until the engine cools, and then limp home.<br /><br />The lower unit has a water pump, called an impeller, which looks like a rubber starfish. The arms can get brittle, wear down, and worse, break. If the pump can't circulate the water to the power head, it heats up to much. These motors are water cooled. There is a thermostat in the upper cylinder head and a sensor pick up for temperature which is wired to the warning horn. It sounds to me like your mechanic suspects that the pump (impeller) needs to be changed.<br /><br />Some of the people here service their impellers once a year, some less often. It is cheap insurance.<br /><br />Good luck!

 

[Royboy]

Re: Engine Overheating or What?

Originally posted by funpilot:<br /> The warning horn is the overtemp buzzer. It's telling you to reduce throttle until the engine cools, and then limp home.<br /><br />The lower unit has a water pump, called an impeller, which looks like a rubber starfish. The arms can get brittle, wear down, and worse, break. If the pump can't circulate the water to the power head, it heats up to much. These motors are water cooled. There is a thermostat in the upper cylinder head and a sensor pick up for temperature which is wired to the warning horn. It sounds to me like your mechanic suspects that the pump (impeller) needs to be changed.<br /><br />Some of the people here service their impellers once a year, some less often. It is cheap insurance.<br /><br />Good luck!

 

[Royboy]

Re: Engine Overheating or What?

Thanks for the fast response. Is this something I can do my self or do I have to take the boat to the mariana and have it fixed. I probably should buy myself a manual. Thanks again and have a nice day. vathinman@yahoo.com

 

[funpilot]

Re: Engine Overheating or What?

I dunno Royboy,<br /><br />It depends on how comfortable you are with tools. You do need a manual to review the job first, and on some of these motors, getting at the impeller can be tough if it hasn't been done for a while (corrosion, stuck bolts, etc.) Why don't you check out a manual at the library, or buy one on this site, and decide if you can tackle this? Doing these kinds of tasks can be a good way to learn and gain confidence in your motor.<br /><br />Good luck

 

[halfpint1]

Re: Engine Overheating or What?

you can get a manual for you motor at marineengine.com but it will take about 3weeks to arrive. Make sure you have the correct ID#s for your motor.They offer a manual package that includes the service manual,parts catalog,and the maintenance manual but it costs somewhere around $80 to $90 which includes S/H.These manuals are informative but you better have some mechanical abilities before you try doing the work yourself.

 

[KCLOST]

Re: Engine Overheating or What?

Hold Up!!!!!<br /><br />When you or whoever removed the oil injection system, was the oil alarm system removed also???<br /><br />There are leads going to the oil tank on the engine, and the pump itself....<br />If they are still connected, your alarm will still sound if no oil is present...<br /><br />It's going to be an intermittent "beep, beep, beep" for oil problems.. An overheat alarm is a constant "beeeeeeeeeeeeeep". Which alarm are you having?

 

[Royboy]

Re: Engine Overheating or What?

Originally posted by KCLOST:<br /> Hold Up!!!!!<br /><br />When you or whoever removed the oil injection system, was the oil alarm system removed also???<br /><br />There are leads going to the oil tank on the engine, and the pump itself....<br />If they are still connected, your alarm will still sound if no oil is present...<br /><br />It's going to be an intermittent "beep, beep, beep" for oil problems.. An overheat alarm is a constant "beeeeeeeeeeeeeep". Which alarm are you having?

 

[Royboy]

Re: Engine Overheating or What?

Now you have me thinking. I am not real sure exactly what I heard, “beep beep or the constant beeeeeeeeeeeeeeeep”. I am almost certain it was constant. I am going to check out the wiring to see if are still connected. The guy at the Marina seemed extremely positive that it was a heating problem. I really appreciate the attention to my problem. I will keep you advised.

 

[Royboy]

Re: Engine Overheating or What?

I am going to have the local Boat gent pick up the boat and take a look at the my problem. I fired it up Sunday and I have a nice stream of water coming from the top of the engine. Also I did not get any noise but of course I did not leave it running very long. I really appreciate all the inputs and will let you all know the final outcome. Royboy