Reply
Visitor

Re: C7 High Heat Air Intake Alarm

upon dismantling the engine I have discovered a random rust pattern but very similar in each cylinder from 2" to 0 at the top of the cylinders and now must rebuild, install a factory reman or re power. Was it an aftercooler failure that caused your problem? Was the rebuild less $ and did you sleeve the block or find oversize pistons and rings? Did you completely dismantle the block before removing it. Did you have to buy a new head?
Contributor

Re: C7 High Heat Air Intake Alarm

It was close to 900 hours.  This engine still burns about 12 % more fuel after the rebuild.  Soot is not an issue since the rebuild except a very small amout upon acceleration.  I'm either at 600 RPM or 2300 Rpm.  Very seldom in between, I do go WOT for about 45 seconds on ocassion to "Blow it out".  It was my starboard engine and no water in the oil.

Visitor

Re: C7 High Heat Air Intake Alarm

The history of this C-7 has in it a head replacement at about 900 hrs said to be caused from a carbon build up on the intake valves, I have 1977hrs on the engine now. Before the high heat warnings occured the engine burned about 12% more fuel and would smoke a bit more than the starboard. The cockpit deck would get soot on it when running from 1100 rpm to 2000 rpm. Just wondering if you had the same issues before your cracked head was diagnosed and if it was the port engine. How many hours were on your engine when this happened? Did you have water in the oil? 

Contributor

Re: C7 High Heat Air Intake Alarm

Cracked cylinder head.  Required engine haul that was not easy and a total rebuild.  Had to strip engine to the block, attach plate to block to barely clear getting it out.  Floor deck can be removed IF you don't have a tower.

Visitor

Re: C7 High Heat Air Intake Alarm

did you find out what was causing the problem? I have the same issue except I have not checked the sensor yet.

New member

Re: C7 High Heat Air Intake Alarm

Need to clean the aftercooler core. Maybe aftercooler was clogged up by carbon,.

Super Contributor

Re: C7 High Heat Air Intake Alarm

Engine has all the symptoms. Carbon on intake air temp sensor, high intake temp right after starting, and smoke on acceleration.
Contributor

Re: C7 High Heat Air Intake Alarm

Wow,  That's scary and you sound pretty sure its the problem.

Super Contributor

Re: C7 High Heat Air Intake Alarm

One or more of the intake valves is leaking, allowing hot gases back into the intake. The cylinder head will need to be replaced.
Highlighted
Contributor
Accepted Solution

C7 High Heat Air Intake Alarm

At startup within a minute or two I get a High Heat Intake Air Alarm.  I replaced the sensor to no avail but it did have quite a bit of carbon buildup on the old sensor.  In the beginning I could shut down and it would reset after one or two attempts and run fine.  It also bogs down and blows black smoke in the range of 1100 to 2000 RPM then catches up with the port engine and runs fine.  Right now I'm not operating it until its resolved.  I do have a call in to Alban Cat in Savage, MD awaiting a response and hopefully will be back boating shortly.  Any ideas on this problem I can try in the meantime?  Will post results once mission is accomplished.