Water Temp Gauge Prob

[dorelse]

Ok, taking my 'new' '96 Glastron GS-185 w/3.0L Mercruiser out for my the first time.<br /><br />I've noticed and issue with the temp gauge. When we're moving at a decent speed, the temp gauge reads the correct engine water temp, 135-150 degrees. When stopped, or moving slowly, the gauge immediately tops out, and bounces around erractically.<br /><br />I know that it can't be the correct temp as its boucing a lot, and even from a cold start it jumps right to the Max position. Get the boat moving, and it reads correctly. <br /><br />I know that it was maitained well, and has very few hours on it, could a broken impeller cause this? <br /><br />Any ideas? I'm new to I/O's, and did search, but didn't find anything I thought I could start with in the Search results.

 

[tommays]

Re: Water Temp Gauge Prob

http://www.tflx.com/tech.html <br /><br />this site will tell you how to trouble shoot a guage problem<br /><br /><br />tommays

 

[dorelse]

Re: Water Temp Gauge Prob

Thanks for that. A bigger concern of mine is this: Could the gauge flakiness at idle is telling me that no water is getting to the motor, or that not enough is pumping through etc? <br /><br />These instructions aren't going to help with that, as well as if that gauge reads correctly at speed, then why wouldn't it work properly at idle?<br /><br />Any thoughts?

 

[jeff13601]

Re: Water Temp Gauge Prob

You would know if no water were getting to the motor. You probably have an impellor problem or some type of blockage

 

[tommays]

Re: Water Temp Gauge Prob

even from a cold start it jumps right to the Max position<br /><br /> based on your description you guage is not working correctly <br /><br /><br />you may need a water pump ,thermostat ,water hoses ,ect and if you dont have a service record for the boat you would be much better off just replaceing them so you no what kind of shape there in<br /><br /><br />you boat is right at the age were most of the rubber parts ,drive bellows ,exaust bellows ,ect are really at or near the end of there recomend life <br /><br />they get OLD even if the boat is not used<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=24;t=010458#000000 <br /><br />i hold some kind of record FOR letting it go way to LONG and not damageing anything<br /><br />BUT i owned the boat new ,the drive was never left trimed up ,allways compleatly covered, the water pump never saw a dry second ,and the hours are very low<br /><br />BUT there is no way it would have run through the 2005 season without several disasters that would have cost me thousands of dollars if i had tryed to get one more year out of the rubber<br /><br />tommays

 

[dorelse]

Re: Water Temp Gauge Prob

Ok, had it on the water again today...beautiful day in Iowa. @85 degrees, light winds...nice.<br /><br />Anyway, gauge is still jumping all over the place, but I can put my hand on the motor. Its very warm, can hold my hand on the valve? cover for say 20 seconds without issue, but not forever. No overheating temp alarm, and ran the engine long enough (an hour) for it to have definitely needed some type of cooling. <br /><br />So its being cooled, definitely. Need to start checking the gauge now, ran the wires, seem to be fine, guess only the sender or the gauge are left.

 

[Don S]

Re: Water Temp Gauge Prob

Well, if you can hold your hand on it for 20 or 30 seconds, then you are running between 160 and 170°. <br />HOWEVER, impellers and bellows and other rubber parts don't last forever, but lucky for you they are not your problem.<br />Your problem sounds like a sender acting stupid, and intermittently which makes it a bear to find.<br />If you can afford it, replace it. But make sure the electrical wiring is in good shape first. Not only at the sender but at the temp gauge also.<br />You are also one of the lucky ones. There is a Mercruiser service manual for both your engine and drive online.<br />Save the links and use them and read them and save them to your computer for future reference (If you have Adobe Acrobat 6 or newer)<br />When you go to the links below, and find the index, just move your cursor over the page to find the links to the different sections. The cursor will change.<br /><br /> Engine Service manual #13 <br /><br /> Alpha I Gen II Service Manual #14

 

[dorelse]

Re: Water Temp Gauge Prob

Thanks Don S, appreciate the links and have already saved them to my iBook. Thanks again!