GT 40 over heating at idle
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=41647
Printed Date: April-29-2024 at 5:53am
Topic: GT 40 over heating at idle
Posted By: scottyb1838
Subject: GT 40 over heating at idle
Date Posted: July-31-2017 at 8:27pm
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My GT40 engine in over heating at idle. I've replaced the water pump,thermosat 160 degree, checked water strainer and hoses. Anybody have any idea why I'm running hot? It cools down when I'm running down the water. 97 Ski Nautique gt40 engine. ------------- Scott Brasher |
Replies:
Posted By: fgroce
Date Posted: July-31-2017 at 8:37pm
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Hi and welcome to the forum. Have you replaced the impeller? Did you use the OEM brand.? The aftermarket one's may not hold up as well. Most people recommend changing them out every one to two years. Make sure you do not see any bubbles in the strainer, that will indicate a air leak. Make sure the gasket is not missing. Hope this helps. ------------- FGroce 88 Ski Nautique For 28 years Now 2002 Ski Nautique |
Posted By: scottyb1838
Date Posted: July-31-2017 at 9:09pm
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The water pump can as a whole assembly with a impeller. Strainer seem to be fine also put Teflon tape around to make sure no leak. ------------- Scott Brasher |
Posted By: 63 Skier
Date Posted: July-31-2017 at 9:45pm
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Not sure I understand your water pump comment in your last post. Running it on the trailer is a good way to see how the water flow is at idle. I suggest you use a "Timmy Tee" setup, which is ideal for running on the trailer and mimics the pull of the raw water pump when the boat is in the water. You can watch the water flow out the exhaust, see if you have decent flow at idle or only when rpm are elevated a bit. Checking flow at idle would be a good start. ------------- '63 American Skier - '98 Sport Nautique |
Posted By: swamp demon
Date Posted: July-31-2017 at 9:59pm
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Is the o-ring in the strainer. How about the elbows that screw into the strainer, they may need sealed. Check inlet side of tranny cooler ------------- Clear Lake,Indiana |
Posted By: fgroce
Date Posted: August-01-2017 at 11:23pm
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Since you replaced the entire RWP you did not put it in upside down did you. It is real easy to do. ------------- FGroce 88 Ski Nautique For 28 years Now 2002 Ski Nautique |
Posted By: KENO
Date Posted: August-02-2017 at 8:01am
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fgroce wrote:Posted By: fgroce
Date Posted: August-02-2017 at 8:30am
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Missed that later on. ------------- FGroce 88 Ski Nautique For 28 years Now 2002 Ski Nautique |
Posted By: MourningWood
Date Posted: August-02-2017 at 3:15pm
| Sounds like possible debris in the trans cooler or exhaust manifolds, a 'clog' that is overcome by the greater "at speed" cooling water amount. |
Posted By: TRBenj
Date Posted: August-02-2017 at 3:19pm
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Tee is not good for troubleshooting cooling system. Blockages will usually manifest themselves as overheats at speed, same as a failing impeller. Idle overheat is almost certainly a small air leak between rwp and hull pick up. Sounds like you missed it the first time, look at all those hoses and connections again. |
Posted By: KENO
Date Posted: August-02-2017 at 4:05pm
I'm kinda wondering what overheating at idle means? Are you boiling water or is it just heating up some? Numbers would be good to go by, like what it normally runs at, what it heats up to Also what led to the problem initially and what made you decide to replace the old pump In other words give a little more info
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Posted By: fgroce
Date Posted: August-02-2017 at 5:40pm
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I wonder is it really overheating or maybe a voltage issue at idling giving a false overheat? How about using an IR temp gun and checking the temperature. ------------- FGroce 88 Ski Nautique For 28 years Now 2002 Ski Nautique |
Posted By: scottyb1838
Date Posted: August-03-2017 at 4:44pm
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When Idling I will get 185 +. Normally runs 160. When I pulled the RWP groves had worn into the back housing and wear plate. I thought they would've been enough water getting by to cause the overheat. ------------- Scott Brasher |
Posted By: scottyb1838
Date Posted: August-03-2017 at 4:46pm
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Thank you. Should I pull off the hose and connection and re seal each? ------------- Scott Brasher |
Posted By: TRBenj
Date Posted: August-03-2017 at 5:06pm
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Pull off each hose and inspect for cracks along the length of the hose, damage from previously overtightened clamps, proper mating depth, and inspect for damage to the hard parts. Trans cooler is especially vulnerable to damage from overtightening. Strainer bowl needs to be TIGHT (so tight that you probably won't be able to remove it without a strap wrench) and obviously the o-ring needs to be in place and in good shape. |