454troubles

I purchased a new 39'Cruisers express in 2000.Unfortunately it has a pair of 454 7.5 fuel injected engines. It only has 650 hours on it. I recently had to replace the starboard engine. Then I reolaced a lot of the port engine oil coolers ,,risers ,,manifolds ,heat exchanger and on and on. Here is my problem The buzzer alarm keeps going of from( I even replaced the buzzer alarm ) f. I have switched all 7 sensors. I even installed a new battery. Nothing seems to help Can anyone out there shed some light if they have had similar experience. I live in Florida and even installed a "fresh water flush " system in it years ago. It is driving me crazy Any comments I do not even know if this is the correct forum to be in

3pointstar

I'm not a mechanic - my first inclination would be to check ALL of the fluid levels - the outdrive and the depth sensor have caused me more "heart attacks" than you can shake a stick at - only to learn that I incorrectly set the depth alarm and was a little low on outdrive oil. Since it looks like you replaced a number of components - you may have inadvertently omitted or incorrectly connected sensor wires -- It may be less expensive in the in long run to have someone with a scanner - scan the engines and see if they are throwing an error code.

sorry I couldn't be more help

3pointstar

BUP

iTrader: (9)

First and foremost what in the heck engine brands do you have, then what ecms are used. 39 ft cruisers used a array of engine brands from Crusader, to marine power to Mercruiser to Volvo and so on plus what engine did buy for replacement and from whom and new or used ??

also what type of alarm --- beep beep or a solid Beeeeeeeepppppppp

much important info is missing here and have no idea how one would even guess whats wrong with your app

2. is whats your engine serial numbers ?

3 is in most 39 ft cruisers do not have outdrives so the gear oil bottle would not be the issue unless you have outdrives I/O s.

4 is how about scan of the engines instead parts changing - that's one way to find the source of the problem

5. Prob possible could be a general 1 or a general warning 2 alarm in which would mean --- trans temp high and or low fluid pressure or low motor oil pressure, . even if your gauges read normal. Try changing out the senders for these. This would be my guess without knowing any of the important info that is missing plus not a scan for the engines.

BUP

iTrader: (9)

if you bought a I/O programed ECM engine repower - and you have inboards with a tranny then your problem is the ECM wrong ecm calibration from I/O to inboard application. The ecm use a specific calibration for ignition and propulsion set ups. So if they do not match there will be alarms.

SO YOU BETTER KNOW WHAT YOU BOUGHT FOR THE REPLACEMENT ENGINE and is it CALIBRATED FOR YOUR EXACT PROPULSION AND IGNITION SET UP ???? If not you will have a alarm all the time and depending on ECM guardian mode will be set limiting RPMs - again GUARDIAN MODE depends on which ECM you have for the 454 s and or the repower

I see this a lot from owners whom buy brand new engines from Michigan motors or repower centers and are clueless about the ecm calibration needs to match the propulsion set up of their app . See this once per week during full blown boating season... Very common from the end user and marine shops whom are not properly trained. when buying repowers from where ever -- new and used

454troubles

Well first I am new at this. They are Mercs 454 7.4l MPI fuel injected Gen VI-29. I have switched all sensors from the good engine to this one I even switched the ECM. . Still buzzing. Anyone got any ideas where I can purchase a engine analyzer so I can retrieve the codes

dereknkathy

If it didn't buzz before you replaced the engine and buzzes after, you have something hooked up wrong. Best chance is having alarm wire on gauge sensor.