Heat Alarm

[chipster]

I have a 1994 OMC jet in a Boston Whaler, the heat alarm goes off after about 15 minutes of running time. The water is clearly pumping throught the engine and can be seen exiting the rear housing in a healthy stream of water. I have flushed the engine after every use and feel very confident the engine is clean. Has anyone a suggestion where to look or what steps to take? Dealer is of no help since he states OMC is no longer in business and he can not get parts if needed.

 

[12Footer]

Re: Heat Alarm

First, find a new DEALER. He is trying to sell motors.<br />I would replace the impeller and t-stat,even if it pumps water, if it hasn't been changed in the past year or so. Impellers are a normal wear item, and as such,should be in the "planned maintainance" book.<br />See how the alarm acts with a new impeller.<br />If it still goes into alarm, check the sender.<br />I know it sounds backwards (in both time and price-wise), but I wanna hear you got it back on the water.

 

[hondon]

Re: Heat Alarm

From your post I am guessing that this is a cross V OMC with a san leandro factory or ordered jet conversion.If so this jet pump sometime doe's not provide sufficient water to the water pump to push the poppet valves in your t stat housing off their seats thus creating an overheat with plenty of water comming out the pee hole.San Leandro makes a fin for the shoe of your jet that might help.

 

[chipster]

Re: Heat Alarm

Hondon<br /><br />Can you give me more spacific information regarding the fin you describe in your message. How can I identify if I have the unit you describe, whrer can I purchase one, and how much will it cost? The unit is a 115 OMC twin v motor with, I believe an OMC jet drive, at least it has an OMC logo on the rear out put housing.

 

[rmeyer33]

Re: Heat Alarm

Chipster -- I just purchased a 1994 Boston Whaler Rage 15 and I have the same issue. I can run for about 30 minutes and them I get the horn. Today I turned it off and back on and the horn went away. Just like you stated, the engine is spraying a good stream of water out. Please let me know if you found a solution and I'll do the same. I plan on getting the actual temp of the engine the next time it does this to find out if the sensor is bad. <br /><br />Thanks.<br />rmeyer@tmg-mad.com

 

[chipster]

Re: Heat Alarm

rmeyer33 - I found the problem to be the thermostats. The parts cost approximately $50 however, the task was difficult due to the location of these parts on the lower rear of the engine block. I found it necessary to remove the rear seat/deck cover which simplified the process. It was necessary to use a mirror to locate the popit valves and springs after the cover was removed. Suggest you visit the parts counter and look at their parts book to better understand the location of the parts.

 

[rmeyer33]

Re: Heat Alarm

Chipster -- Thank you very much for the reply. It will save me alot of time and guessing. I will be replacing the t-stat this week. Thanks again.