496 Hi Temp Question
08-30-2011, 09:16 AM
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496 Hi Temp Question
PLEASE HELP!
I have a 2005 496 I just bought with 100 hours that keeps alarming high port manifold temp but only when the boat is run wot. I found a ton of sand in the manifold and heat exchanger but cleaned boat, replaced the raw water pump as well as the manifold temp sensor but still have the problem. On the hose at idle it appears to have less water coming out of the port exhaust but considering its the farthest from the pump I would imagine it would be normal.
Should I just remove both manifolds, risers, and the heat exchanger and have them cleaned ultrasonically or do you guys have any ideas of where to check. I really want to enjoy my new boat but this is really becoming a pain!
Thanks!
I have a 2005 496 I just bought with 100 hours that keeps alarming high port manifold temp but only when the boat is run wot. I found a ton of sand in the manifold and heat exchanger but cleaned boat, replaced the raw water pump as well as the manifold temp sensor but still have the problem. On the hose at idle it appears to have less water coming out of the port exhaust but considering its the farthest from the pump I would imagine it would be normal.
Should I just remove both manifolds, risers, and the heat exchanger and have them cleaned ultrasonically or do you guys have any ideas of where to check. I really want to enjoy my new boat but this is really becoming a pain!
Thanks!
08-30-2011, 09:58 AM
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What is your water pressure?
Also, how do you hook the hose up? Muffs on the drive? I have nada few friends with Bajas in which the T flush fitting in the engine compartment between the drive and SWP gets gummed up with sand/debris, and will overheat alarm only at high speeds.
Also, how do you hook the hose up? Muffs on the drive? I have nada few friends with Bajas in which the T flush fitting in the engine compartment between the drive and SWP gets gummed up with sand/debris, and will overheat alarm only at high speeds.
08-30-2011, 10:34 AM
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I do not have a water pressure gauge on the boat, I do however plan to add one over the winter.
I am flushing it with muffs and also blocking the low water pick up with the Mercury adaptor.
I am flushing it with muffs and also blocking the low water pick up with the Mercury adaptor.
08-31-2011, 12:03 AM
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Try swapping your exhaust manifolds and risers to the other side and see if the overtemp issue follows the move. This will tell you if the problem is in a particular manifold and riser or whether its in the raw water system feeding the exhausts.
Best Regards,
Ray @ Raylar
Best Regards,
Ray @ Raylar
08-31-2011, 01:50 AM
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Hello
Take off and clean the starboard drain system. There`s a little plastic ball that should seal from water getting in to the manifold before it has gone trough "around" the motor. A part of the water is getting out directly trough the starboard manifold and then you have much less water to cool the rest of the engine and port manifold will get hotter than starboard. Had same issue just cleaned it up and promblem solved.
Part nr 3 in this picture
http://www.mercruiserparts.com/Show_...lbow+and+Riser
Take off and clean the starboard drain system. There`s a little plastic ball that should seal from water getting in to the manifold before it has gone trough "around" the motor. A part of the water is getting out directly trough the starboard manifold and then you have much less water to cool the rest of the engine and port manifold will get hotter than starboard. Had same issue just cleaned it up and promblem solved.
Part nr 3 in this picture
http://www.mercruiserparts.com/Show_...lbow+and+Riser
09-01-2011, 08:39 PM
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Hello
Take off and clean the starboard drain system. There`s a little plastic ball that should seal from water getting in to the manifold before it has gone trough "around" the motor. A part of the water is getting out directly trough the starboard manifold and then you have much less water to cool the rest of the engine and port manifold will get hotter than starboard. Had same issue just cleaned it up and promblem solved.
Part nr 3 in this picture
http://www.mercruiserparts.com/Show_...lbow+and+Riser
Take off and clean the starboard drain system. There`s a little plastic ball that should seal from water getting in to the manifold before it has gone trough "around" the motor. A part of the water is getting out directly trough the starboard manifold and then you have much less water to cool the rest of the engine and port manifold will get hotter than starboard. Had same issue just cleaned it up and promblem solved.
Part nr 3 in this picture
http://www.mercruiserparts.com/Show_...lbow+and+Riser
Thanks for the help!
