Help With Searay alarm

[ppwhite]

I have 1999 searay 400 Dancer. with two 7.4 Horzions motors. It bought this boat in October of 2010 with the starboard motor blown. Number 5 piston was melted. I replaced the motor and got it running but I have two problems I cant figure out with the boat. First is a constant alarm. I have checked the tranny temp siwtch /Oil Siwtch /Coolant temp siwtch. I am traced the green back to the pcm that is grounding the alarm to turn it on. Everything checks out. I switched pcm with the port motor which has no alrams. I can not firgue this alarm out at all. Oil pressure is 45 psi engine temp is 160 f and tranny temp switch is open. Something is telling the pcm to turn the the alarm on. This boats computer has been changed from MEFI 3 to MEFI 4. I also have a code 81 injector circuit A and B low voltage code . Voltage is good checked each power wire to injectors with a headlight.Please help I need it ths

Paul
Port Engine serial # OL302958
Trasmisson Blue Tag Velvet 20-02-005
Starboard Engine Serial # OL302932

 

[Bondo]

Re: Help With Searay alarm

I have 1999 searay 400 Dancer. with two 7.4 Horzions motors. It bought this boat in October of 2010 with the starboard motor blown. Number 5 piston was melted. I replaced the motor and got it running but I have two problems I cant figure out with the boat. First is a constant alarm. I have checked the tranny temp siwtch /Oil Siwtch /Coolant temp siwtch. I am traced the green back to the pcm that is grounding the alarm to turn it on. Everything checks out. I switched pcm with the port motor which has no alrams. I can not firgue this alarm out at all. Oil pressure is 45 psi engine temp is 160 f and tranny temp switch is open. Something is telling the pcm to turn the the alarm on. This boats computer has been changed from MEFI 3 to MEFI 4. I also have a code 81 injector circuit A and B low voltage code . Voltage is good checked each power wire to injectors with a headlight.Please help I need it ths

Paul
Port Engine serial # OL302958
Trasmisson Blue Tag Velvet 20-02-005
Starboard Engine Serial # OL302932

Ayuh,.... Welcome Aboard Paul,...

Donno what's triggerin' yer alarms,...
Just wanted to mention,...
I'd venture a Guess that a lean condition caused the old motor to burn down...

Double, Triple check the boats fuel systems from tank vents to the fuelpumps....

 

[chaswor]

Re: Help With Searay alarm

Gear lube level?

I have 1999 searay 400 Dancer. with two 7.4 Horzions motors. It bought this boat in October of 2010 with the starboard motor blown. Number 5 piston was melted. I replaced the motor and got it running but I have two problems I cant figure out with the boat. First is a constant alarm. I have checked the tranny temp siwtch /Oil Siwtch /Coolant temp siwtch. I am traced the green back to the pcm that is grounding the alarm to turn it on. Everything checks out. I switched pcm with the port motor which has no alrams. I can not firgue this alarm out at all. Oil pressure is 45 psi engine temp is 160 f and tranny temp switch is open. Something is telling the pcm to turn the the alarm on. This boats computer has been changed from MEFI 3 to MEFI 4. I also have a code 81 injector circuit A and B low voltage code . Voltage is good checked each power wire to injectors with a headlight.Please help I need it ths

Paul
Port Engine serial # OL302958
Trasmisson Blue Tag Velvet 20-02-005
Starboard Engine Serial # OL302932

 

[ppwhite]

Re: Help With Searay alarm

Thanks for the help. No gear lube, inboards. Yesterday I switch the complete motor wiring harness from one motor to the other and the problems still occurs in the starboard motor code 81 and constant alarm. So far I have replaced all injectors and two different computers and wiring harness and the problem is still in the starboard. The marnia I am at cant hook there CDS Mercrusier scan tool up for 3 weeks because they are so far behind. I am lost with this thing. I was hoping DOn S would have some input on this. I would appreciate anyone that could give me any input on this . I hate not being abled to fix something.

 

[Don S]

Re: Help With Searay alarm

I have been looking, just haven't found anything. Your last reply made it even harder to figure out from here.

 

[Don S]

Re: Help With Searay alarm

Do you still have the alarm if you disconnect the main engine harness from the engine?

 

[fossill]

Re: Help With Searay alarm

Voltage is good checked each power wire to injectors with a headlight.

Paul
Port Engine serial # OL302958
Trasmisson Blue Tag Velvet 20-02-005
Starboard Engine Serial # OL302932

Not too sure what the service manual says in your case, but just a heads up, test lights around fuel injection electronics is bad news. A proper volt/ohm meter is the way to go to avoid "frying something".

 

[911S]

Re: Help With Searay alarm

Don't know if this will help but I had an alarm that I couldn't figure out just like you. Ended up being the built in depth sounder shallow water alarm was bad and was triggering the alarm.

 

[Fireman431]

Re: Help With Searay alarm

HAve you cleared all the old bad codes from the computer? Is it possible that the alarm is being triggered by the computers memory from the blown engine?

 

[dubs283]

Re: Help With Searay alarm

when you say you checked the temp/oil switches, how so??

have you tried swapping any of em with the port engine to see if the problem moves??

 

[ppwhite]

Re: Help With Searay alarm

Thanks for all the help. I have cleared the codes with a mercruiser scan tool and code 81 keeeps returning. If i disconnect the main engine harness alarm does go away because the ecm grounds the alarm so i am just taking the ground side away from the alarm. As far as checking each switch i checked the ohms verses the psi or temp acccording to the chart in the mercruiser manual. This is a crazy problem . i really need a mfei 3 to Mefi 4 pin chart for ecm. I was hoping somebody experienced the same problems.

 

[dubs283]

Re: Help With Searay alarm

and you get this same code 81 even with swapping the ecm's??

 

[ppwhite]

Re: Help With Searay alarm

That s correct code 81 stays with the motor. I have swapped ecms wiring harness and sensors.

 

[dubs283]

Re: Help With Searay alarm

don't know if they're long enough but you may try connecting the port side boat harness to the stbd engine harness

just sounds like you have done everything enginewise - could be a boat harness issue

 

[muc]

Re: Help With Searay alarm

I Ran your serial numbers on mercnet. Sorry to say this boat has been a problem child. Might be best to ask your dealer to get the TAM involved. This problem was last covered under warranty in 2009. It froze the CDS at that time and it looks like Merc replaced the mefi3 to mefi4 harness to correct it. Have you swapped the complete elec harnesses from motor to motor? It might be worth the effort. Looks like every thing else has been replaced at one time or another. In 2004 it was #6 that had water on top of the piston and got a new long block. Its hard to tell for sure because I think the serial numbers might have gotten mixed up between the two engines. Looks like this boat has had one long block, one valve job, two closed cooling kits, two sets of new style exhaust manifolds and two mefi4 upgrades plus some other stuff under warranty from 2000 to 2009. This would be a fun problem to track down, trouble will be trying to find somebody willing to pay what its going to take.

 

[ppwhite]

Re: Help With Searay alarm

Muc thanks for all the research.I did the same thing about 4 weeks ago and just shook my head. I really appreicate very thing you did. Listen to this. After i did all this above I installed a mefi 3 computer and the boat ran great. No codes no alarm.Installed the mefi 4 and all this comes back. I am not sure where to go here possibly get 2 mefi threes with stock programing . Merc wants 1400 they said they might be able to get one for still . I need two of them. Where to go from here any idea?? Listen is crazy. If you look at the history all this started when they put the Mefi 4 in this boat. Any info helps

 

[Don S]

Re: Help With Searay alarm

After i did all this above I installed a mefi 3 computer and the boat ran great. No codes no alarm.Installed the mefi 4 and all this comes back. I am not sure where to go here

I may be stupid for asking this, but why don't you stick with the MEFI 3 ECM if it works ??????????????
Why did you go with the 4 to begin with?

 

[muc]

Re: Help With Searay alarm

Mefi4 installed long before he bought boat.

 

[Don S]

Re: Help With Searay alarm

Mefi4 installed long before he bought boat.

Good point.

I guess the question still stands, why not use the MEFI-3 instead of fighting something that just doesn't work on that engine. Granted, it would be nice to know what is actually causing the problem, but at what expense. Backing up to MEFI-2 would be impossible with the connectors setup for 3 and 4. I know the pinout is different between 2 and 3.

 

[ppwhite]

Re: Help With Searay alarm

Mefi. 3 is not mine i borrowed it.from boat with same motor.the mefii 4 was installed a while ago i want to get rid of the mefi 4 and jumper harness.i need to find where to get mefi 3. I want reputable person you never who u r dealing with on the internet now.days.i.have not.read anything good about mefi 4.