MD7 overheating

[Rob Hindman]

My MD7a is overheating under load. The thermostat and impeller have been replaced. I noticed a corroded water line before the pump and a dripping leak from the buttom of the muffler. I know that neither problem is desirable. Could either or both of these problems lead to overheating? My mechanic won't be able to look at the boat until late next week. Thanks for any ideas or information.

[Jim Lewis]

My MD7a is overheating under load. The thermostat and impeller have been replaced. I noticed a corroded water line before the pump and a dripping leak from the buttom of the muffler. I know that neither problem is desirable. Could either or both of these problems lead to overheating? My mechanic won't be able to look at the boat until late next week. Thanks for any ideas or information.

Does the temperature gauge cycle while under load? If so
chances are there is blockage from corrosion. Normally
removal of the exhaust manifold and cleaning out will help.
If you have alot of silt in your area that may be causing
the problem. If your engine has the original type muffler
replace as soon as possible, for it will only get worse and
cause more corrosion in other areas where it drips....good
luck. Email if you have any questions. Jim



Sailonthesea@aol.com

[BOB]

AT THIS TIME OF THE SEASON, START WITH THE BASICS, CHECK YOUR RAW
WATER INTAKE, THE FLOW COULD BE REDUCED DUE TO MARINE GROWTH WHICH IS WHY IT IS RUNNING HOT UNDER LOAD

[Joe Valinoti]

My MD7a is overheating under load. The thermostat and impeller have been replaced. I noticed a corroded water line before the pump and a dripping leak from the buttom of the muffler. I know that neither problem is desirable. Could either or both of these problems lead to overheating? My mechanic won't be able to look at the boat until late next week. Thanks for any ideas or information.

My suggestion is to take the discharge hose off of the pump and make sure there is a large volume of water coming out. Do this with a cold engine and don't run longer then a minute. Then, with the engine at operating temp. pull the discharge hose from the engine going into the exhaust and also check for water volume don't run for more then 30 seconds. If there is plenty of water, then pull the manifold and check for blockages.



vwman@coastalnet.com