Loss of power

kennydalglish

I hate to revive this link but unfortunately my issue original issue came back.  So that is now 2 sensors replaced that temporarily took care of the beeping and loss of power issue that are now no longer working.  I am starting to think the issue lies electrically ?  Waiting to put the boat back in the water for yet again more troubleshooting.

JoeStang

Yeah seems very suspect that you would have that many go bad. Maybe theres a short somewhere and its sending too much or too little power to the sensor and killing it? I would trace the wiring from the sensor to the ECU and make sure nothing is bad. Maybe even replace the pigtail that plugs into the sensor?

mattie

@kennydalglish

Hey Kenny,
What about something else altogether?
We had massive power loss in port motor last season. Alarms etc. Backfires. Ended up the fix was a new cap/rotor/plugs.....back to perfect. 2014 boat all Merc stuff.

I didn't know these newer electronic ignition boats still had cap/rotor.

Not likely the replacement TPS's are actually all failing on you. 

rasbury

Just had the same experience...night and day.

kennydalglish

Just an update.  Had my marina service guys hook up a laptop diagnostic instead of my mechanics ancient tool.  They said the TPS code was still there and they went ahead and cleared it.  Now just need to go down to the boat to give it a run and pray for no beeps.  Mattie,  Good advice.  about to replace my wires and plugs as well since they are due.  Replaced Cap and rotor last year.    Rasbury,  let me know details ??

kennydalglish

Joe,  I also ordered a connector that plugs into the TPS to replace in case one or all 3 of the pins are loose and becomes worse under vibration.

kennydalglish

I hate to say it but the saga continues.  Having a real good time with this boat that I bought last season.  Latest:  Marina mechanic hooked up real time laptop diagnostic and the beeps are being caused by no oil pressure at low RPM.  History:  Had total engine rebuild done last season at a cost of 6K.  Oil has been changed after break in period with 24W40 Mercruiser oil.  Oil Level is good.
What are the things you would check ?  In order of easiest to hardest ?

YYZRC

Oil pressure sender?

I had a 5.7 Volvo where the elbow between the block and the sender cracked. Readings went wacko and it leaked a tiny bit of oil. Pretty cheap part to replace. 

Grahamu

Not too many things to check, oil pressure sender first. Did they rebuild or change the oil pump during rebuild.

kennydalglish

Thanks Grahamu.  He replaced many things during rebuild but not the oil pump.  On a Mag 350 where would the oil pressure sender be located ? and is it accessible for normal people or only for small flexible people with tiny hands ?

Grahamu

Not sure I'll check the manual, probably on the side of the block.

Grahamu

Here is a YouTube link not sure if your engine would be the same.

Replace a Bad Block Pressure Sensor mercruiser 350 MAG Boat Engine - 8M6000623 - YouTube

kennydalglish

Grahamu,  looking at pics of my engine.  I dont think I will be that lucky.  May have to break out the manual.