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KAD43 Jacket Water Temp at 195 and sometimes higher

soundnav

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"One of my KAD43's runs co

"One of my KAD43's runs consistently hotter than the other - especially when carrying a large group of passengers (20+). I have verified the temp at the thermostat housing with an IR thermometer.

A couple of questions:

Can an improperly timed injector pump / or an excessive fuel issue cause a diesel to run hot?

If so, how do I adjust the injector timing or the amount of fuel being metered to the injectors?

Some history:

Dockside at idle, both engines are at about 100 degrees. When running at 3,000 rpm's, the port engine temp is around 195 - and with a load of passengers, the temp slowly creeps up toward 200 degrees. All is well on the starboard engine - it consistently runs at 180 - even with a load of passengers.

I've been through the raw water and fresh water cooling systems on the port engine more than once and have found nothing.

I have swapped, cleaned or replaced the following:

thermostats (replaced, swapped)
heat exchanger (cleaned)
aftercooler (cleaned)
raw water impeller (replaced)
raw water pump (replaced)
fresh water pump (replaced)
hoses and hose clamps (replaced several)
belts (replaced)

Prior to this, a breach in the head gasket was allowing combustion pressure to pressurize the fresh water system and then caused coolant to be vented into the bilge from the expansion tank. The head gasket was replaced last off-season (head gasket replacement was done by Volvo certified tech).

After replacing the head gasket, the fresh water system is maintaining the proper amount of coolant but the engine continues to run hotter than normal.

I have inspected all components of the raw water system from the thru hull intake up to and including the exhaust riser (heat exchanger, hoses, fittings, strainers, etc...). FYI - the boat is set up with thru hull pick-ups and does not use the outdrive pick-ups.

I have also installed a piece of clear hose at the raw water output side of the heat exchanger and have a steady, solid stream of water there."
 
Are you running a cabin or wat

Are you running a cabin or water heater off that engine?
 
"No - nothing extra is install

"No - nothing extra is installed on the port engine.

In fact, it is the starboard engine that has the power steering pump and fluid cooler (this is the engine that runs at or around 180 degrees under all conditions - even high rpm with a load of 20 or more passengers)."
 
"Do you know if both engines w

"Do you know if both engines were installed about the same time, or has one been replaced or worked on? On thing you could look at are the internals of the riser of each engine. Have the same number of water jacket tabs been bent into the same position? These are variable on installation and have the effect of slowing etc the waterflow in order to lift the working temp for diff climates. Worth checking"
 
HAve you shot each engine with

HAve you shot each engine with laser temp guage to check if slightly corroded wiring is giving you a reading that is slightly off reality?
 
"Thanks Bill - it looks like t

"Thanks Bill - it looks like there were a number of problems here.

Initially, it was a head gasket problem as the exhaust gases were pressurizing the coolant system. Once that was fixed, the affected engine still appeared to run hotter than the other but did not overheat.

After checking things out with an IR temp gun, I eventaully decided to swap the leads to the temp gauges back at the engines. The problem then remained with the same temp gauge indicating either a faulty gauge or as you have suggested - a problem in the wiring.

This entire process was compounded by my being paranoid about the overheating engine and its apparent running hot even after I spent a considerable amount of my severely limited funds trying to cool things down a bit.

The boat goes back in the water soon so I'll have a chance to see what's up in about a week or so.

Thanks for your post."
 
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