ECM on Merc

[aaltamura]

Does anyone know why these fail?? or what life expectancy is??

 

[Don S]

Re: ECM on Merc

They are a small electronic device, therefore they fail for any number of reasons.<br />The life expectancy is till they die. Not trying to be flippant, but most will last longer than the engines they are on.

 

[highaltitude]

Re: ECM on Merc

it has been my experience that the ecm is a reliable component. depending on the year of the motor-i would be careful before replacing the ecm. thorough investigation is ALWAYS GOOD.

 

[aaltamura]

Re: ECM on Merc

I just replaced my engine and upon installation I was told I need a new ECM and fuel pump.

 

[bomar76]

Re: ECM on Merc

OK, we are not mind readers...<br /><br />What was the problem w/ the old engine?<br />What year was it?<br />What year is the replacement?<br />Was old engine EFI?<br />Who told you you need a new ECM?<br /><br />Just a wild azzed guess....did you replace an older carbed engine w/ a new EFI unit? <br />If so, you need an electric fuel pump and the ECM and assciated wiring.<br /><br />BTW,<br />The ECM's can be tested with the proper equipment....

 

[aaltamura]

Re: ECM on Merc

the boat is a 1997 sundancer..the new engine is a remanufactured long block after assembly of new engine, motor would not start...changed the electric fuel pump and would not run right so I was told the ecm needed to be replaced...to test it they swapped ecm from other motor and boat fired right up...what could have casued possible failure....before the engine was replaced the boat was running fine...I had warranty work done on the engine so it had to be pulled and reinstalled.....fuel pump and ecm were working fine before the work on the engine started

 

[Don S]

Re: ECM on Merc

Wow, a 97 sundancer.....whatever that is. NOW, what engine, Mercruiser? Volvo? what size, 3.0L, 5.7L 7.4L?????? Was it MPI, TBI???? Like Bomar76 said, we ain't mind readers here.<br /><br />Possible causes. Someone dropped it on the floor, hooked up battery cables backwards who knows.

 

[aaltamura]

Re: ECM on Merc

Searay sundancer...merc 7.4 mpi

 

[denniz]

Re: ECM on Merc

If you had to replace your fuel pump it was probably due to old fuel gumming it up. It probably did the same to your injectors.(My guess) putting a ecm on it will not fix that. (just my opinion, cant fix a boat with out seeing it first hand)

 

[tommays]

Re: ECM on Merc

i think you have 0 chance of getting the shop to admit they did anything wrong or they would have allready<br /><br />tommays

 

[aaltamura]

Re: ECM on Merc

What could they have done wrong....before the install...they were running the motor in the shop..I was told the fuel pump shorted out the ecm..is this possile?? tell me all you know on this...

 

[GL2238]

Re: ECM on Merc

I have 2001 26 Sundancer with 7.4 MPI B3. ECM has been replaced twice before while under warantee. Its I/O is sensitive to electrical disturbance. Any manual movement, i.e. moving the connector while power is on can cream it. Also if one of the contacts is dirty, engine vibration can cause sufficient arching within the connector to cause it to fail. I was told by a Merc mechanic to spray tuner cleaner (Radio Shack) on the contacts of the module I/O connector every 50 hours or so when used in salt water. He has not had any returns when this is done.

 

[tommays]

Re: ECM on Merc

the ECM is not directly connected to the fuel pump it would normally run a relay that would run the pump<br /><br />everything comeing out of the ECM is some form of solid state relay with no moveing parts and they can fail at any time i dont believe they use any type short circut protection on each output so a bad part or shorted connection could make it fail if it draws more current than it was rated for<br /><br />tommays