High Maniflod temp on C-7

[Reveille75]

Our boat has been laying up for a few months and we were preparing her to go to the yard in Rockport, Texas. Coming back from the fuel dock we got an alarm and the gauge showed a intake maniflod temp of 175. Usually it runs about 75. We thought it could be an intake restriction so we took the air filter off completely. This also alllowed us to see if the turbo was free and it was. We started it up again and the alarm again went off. All we can think is it must be the aftercooler but the engines only have 500 hours on them and don't smoke. Am I missing something?If anybody has any ideas I'd like to hear them.
David

[JD5652]

I would check the sensor or the alarm itself. Make sure you check the ground as well as many alarms and sensor fail "safe" in that if they lose the ground, the alarm will actuate.

[CaptD]

yours are a little more complex than mine but check your water supply as it is likely after being laid up you have a restriction... start with aftercooler and work backwards...500 hrs you are due for aftercooler and heat exchanger service... also impeller parts can travel and clog cooling...good luck.

[Reveille75]

JD:
I think you may have something but we don't know where the sensor is so we'll have to wait until morning to get the Cat guy on the phone. Capt D we checked the impellor and we are getting raw water circulation. What makes me think it's electrical is the way the temp fluctuates with the rpms.
I'll let you know how it turns out. I appreciate your thoughts.
David

[reel fishy]

Have your heat exchanger and raw water system cleaned. The C9s in the Cabo I run were clogged pretty bad at 250hrs. We noticed the problem as our temp was normal at idle and increased as you throttle up. It was very uniform and would slowly increase every time we got up to speed. The boat was purchased used and it sat a lot before my boss bought it. If you pull the raw water hoses off and look at the exchanger tubes you see white crap all over the place. Our mechanic cleaned the system with diluted muratic acid. Cats run absolutely perfect now with normal temps.

[Elite Diesel]

Impeller, Maybe aftercooler dirty.
Screen under the boat may be dirty.

[Reveille75]

Reel Fishy:
You hit it on the head. We took a hose of and looked in the cooler and there was white stuff all over the tubes which I guess is a result of the boat not being started in a while. We are going to try the muratic acid treatment and see waht happens.
David

[Questsportfishing]

I do not know why they started leaking at 600hrs but that was really wierd that they would take a dump and start leaking.. good to have good cat mechanics! "If it's not a Cat...it's a dog...!"

[Reveille75]

Quest:
Please tell me that you found the leaks while at the dock and not planning to go fishing.

[perfectscore]

that is stopping raw water intake, is the raw water valve opened all the way??