Problem with my port engine in my 2003 340DA.............

rgl1100 said:
Amazing thought but I have a few questions before I start tearing into this situation. Although the engine starter doesn't even crank when I depress the starter toggle on the dash, it will crank when I use the emergency cross over. If there was high resistance at the starter solenoid would this respond like this? It's very interesting that my mechanic said that the toggle doesn't seem to trip with low voltage but when 12v is placed on it it trips. Could this be caused by a short across the starter solenoid? If there was a short wouldn't the starter not even work? This scenerio is very very interesting and sounds like a possibility but I really don't want to start dismantling both engines if it's a long shot. Is there any way to test the starter solenoid without swapping it out. Is there a way to test resistance across the solenoid itself? What would a multimeter read if the solenoid was bad? Would it simply show continuity where it shouldn't be? Thank you so much for everyones continued thoughts on this matter. I keep obsessing about it and trying to figure out where to go next...........
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So my mechanic says, because of the tests he's done so far, it isn't the starter or the solenoid but he thinks it might be the starter relay. Can anyone tell me where the relay is located? Is it one of the cubes that sits next to the PCM?
 
I don't understand why he's not already pin pointed the problem. Check battery condition and connections first. As already pointed out, don't ignore grounds. Then go to ignition circuit and see what's delivered to the starter. Then work backwards from there. It sounds like you draw a lot of juice, do you smell or see anything that's gotten hot.
 
Rgl1100, Ok, so you're saying that if you use the "emergency parallel start button the engine WILL START AND STAY RUNNING???
If this is the case, you have a bad battery my friend.


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Kreole Kid said:
Rgl1100, Ok, so you're saying that if you use the "emergency parallel start button the engine WILL START AND STAY RUNNING???
If this is the case, you have a bad battery my friend.


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No. The engine will not run.....at all. What I am saying is if I simply press the port side starter toggle on the dash I get no reaction. No alarm. No crank. After a few seconds the circuit trips. If I then depress the emergency cross over toggle, along with the port engine starter toggle, the port engine will crank( not run) and then the circuit will trip. At no time has the port engine run since before any of this happened.
 
rgl1100 said:
I actually do have smartcraft in the boat and you bring up an interesting thought. Now, several times throughout the season I've had an "aft bilge" alarm that has gone off when I have manually pushed the "bilge" switch on the dash. I know it was wrong but I did not address it immediately because I have checked both the bilge floats valves and pumps in the engine compartment and they have both been fine. I also checked under the main floor and checked the midship pump which was fine. I did find that the shower and airconditioning sump pump was bad and replaced the entire unit. When this all happened I went down and made sure they were working correctly and they seemed fine. Regardless, lets just say for argument sake that there was a problem with the pumps. To my knowledge they wouldn't run on 5v anyway and I don't think they would affect just one engine if they were shorting. Am I thinking about this wrong?
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You are correct in your line of thinking. Those systems are separate (and are 12v).
 
Lazy Daze said:
You are correct in your line of thinking. Those systems are separate (and are 12v).
Click to expand...
So I'm still at square one on this engine problem. My mechanic talked with the guys at mercruiser and he texted me back they they couldn't shed any light on the problem or suggest any other tests be performed by him. He mentioned he was foing to try "one more thing" they suggested and if it didn't work the mercruiser guy with his diagnostics was going to try and "fit me in". I'm very discouraged and, I have to say, extremely disappointed with the expertise I'm finding in my area (Massachusetts). If I ever failed to figure out what was wrong with my systems after this long I'd be dropped like a hot potato. I've been looking at trying to find a good mercruiser mechanic in my area but what I'm finding is that the northeast has fewer due to the short season. I actually can understand this. Why would anyone stick around an area that provided steady work 3-4 months of the year. I know there's inside work to be done but I'd bet that the really good mechanics want to be where there's boating all year round. I'm frustrated and could really use some help...............There should be a quality, capable person out there who has the ability to solve this problem without having to haul the engine out and rewire it from scratch...............
 
rgl1100, Do what you gotta do but I don't think this requires a Mercruiser certified mechanic. Just a good mechanic should do. There's got to be some shops around with ASE mechanics that might be willing to go to your boat. Any of them should be able to find the problem.
 
Woody said:
rgl1100, Do what you gotta do but I don't think this requires a Mercruiser certified mechanic. Just a good mechanic should do. There's got to be some shops around with ASE mechanics that might be willing to go to your boat. Any of them should be able to find the problem.
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I agree Woody. I'm going to keep looking.
 
rgl100, your starter relays are in the engine room. They are likely all very close together. One for each engine, one for the emergency start crossover, one each main battery relay. There should be one for the genny somewhere too. Sometimes these are called solenoids and sometimes relays. They might be inside or behind the main engine room panel.

What are the readings on your main DC panel( in the cabin) amp and volt gauge when you use port side test button? What are they when someone tries to start the engines?
 
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I just came back from being away and went down to check the boat. The port engine now has almost every relay/connection removed. My mechanic has been trying to trace any shorts without luck. It actually doesn't look as though anything has been done since I left and that was 9 days ago.....Now I'm in a real bind. I talked to the mechanic and he states that he spoke with 2 other local mechanics and the local MERC mechanic who all say the only way to fix this is to trace the short. The thing is, even if I wanted to bring in someone else, the harness is completely taken apart. In order for someone to even try to help I'd have to put the whole thing back together and start from square one. I really don't know what to do but all I know is that I want this fixed NOW. Besides giving me the ultimate headache I've begun to ask whether all of this is worth it. This aggravation has been terrible, not to mention the costs. Couple that with the cost of gas I'm beginning to wonder if it's time to head towards a smaller boat or no boat at all.
 
I have had the exact same problem!!!!!!! My engine would actually just die while running with the port engine fuse switch tripping for no apprent reason. The dealer even kept the boat for a week and couldn't duplicate it. What I almost did was override the breaker by holding it down to see where the short was but I never did that. Ultimately what happened was when we were checking connections, there is a big fuse on top of the starter that I believe is 25 amp and it is basically just sits behind the starter wire. It is square with a connection that allows it to be secured with the starter wire. When I accidentally blew that fuse trying to jump the starter, we replaqced it and tightened all connections and (knock on wood) all has been good. It took me almost 2 months of trial and error to figure this out. I agree with the concept that it is a bad connection or it is grounding out somewhere in the circuit. It acted like a dead short on my boat and it was also the port engine. Just my 2 cents for what its worth



rgl1100 said:
I just came back from being away and went down to check the boat. The port engine now has almost every relay/connection removed. My mechanic has been trying to trace any shorts without luck. It actually doesn't look as though anything has been done since I left and that was 9 days ago.....Now I'm in a real bind. I talked to the mechanic and he states that he spoke with 2 other local mechanics and the local MERC mechanic who all say the only way to fix this is to trace the short. The thing is, even if I wanted to bring in someone else, the harness is completely taken apart. In order for someone to even try to help I'd have to put the whole thing back together and start from square one. I really don't know what to do but all I know is that I want this fixed NOW. Besides giving me the ultimate headache I've begun to ask whether all of this is worth it. This aggravation has been terrible, not to mention the costs. Couple that with the cost of gas I'm beginning to wonder if it's time to head towards a smaller boat or no boat at all.
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Eauty,

This is so interesting. Do you think there's anyway I might be able to call you to discuss this. I'm xtremely frustrated right now and could really use some advice. Your problem sounds identical to mine. Originally, the boat ran for a short period before tripping the breaker/fuse on the port engine. Eventually, nothing would even come on (even the low oil pressure alarm that sounds when you depress the starter switch). However, the port engine would crank(not start or run) when the emergency crossover was depressed. It would only crank for a few seconds before the fuse/breaker would trip as you described. According to my mechanic the starter is OK but perhaps the starter and that fuse are two separate entities?................Thank you for your reply. Perhaps we could talk.--Robert
 
Robert, this is a link to a picture (below) of the solenoid switch that is located under the big plastic "Mercruiser 8.1" cover, then under the EIM. If you're standing in between the engines facing aft, right at the diamond plate used as a step down, your port solenoid is just aft of your oil filter. Again, you have to take the black plastic cover off or take out two of the three bolts and rotate it around to get clearance to unscrew the nuts that hold the EIM down. I was a little nervous changing mine for the first time, but as long as you kill the power at the box on the bilge wall, you shouldn't have any concerns with shorting anything out. This particular solenoid should be available at your local marine store. I can get them from Aftermarket Marine down here for $14.95 all day.

I would TRY this, because the symptons that you are describing, minus the breaker tripping, are definitely symptoms of a faulty solenoid. I hope this helps ya buddy:thumbsup:

http://www.amarket.com/images/im106s.jpg
 
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Robert,

I've just gotten caught up on your complete thread. Sorry to hear of your frustrations.

I had a "starting" issue on my port engine that took one year to finally diagnose, but unlike yours it did not involve tripping breakers and the low oil pressure beep always came on when the toggle ignition switch was placed in the "run" position. Intermittently, when this switch was pushed further to engage the starter motor I'd hear a click but the engine would refuse to turn over.

It turned out to be the large ground post on the engine block itself was corroded. I had cleaned the negative posts on the batteries, but did not notice that the black ground wire went from the battery to this post on the engine block itself. Once the ground wires were removed, everything cleaned up and dialelectric greased - no more issues.

Just something else that you can do yourself. It's a long shot, but worth the few minutes to try it.
 
I looked up the part I replaced on my boat and it is called a 90 amp fuse and it is on page 3A-8 of the service manual #33. you can find that service manual online. That fuse sits on top of the starter and is held in place along with the cable from the battery to the starter. I blew that fuse jumping the starter to try and troubleshoot the engine when it died, and since I replaced that fuse the trouble has stopped. Maybe I had a weak fuse or a bad connection, but either way it fixed my issue.
 
Just read all of the replies. Awesome. I will try all of these things. I'm determined to fix this engine!!!
 
Kreole Kid said:
Robert, this is a link to a picture (below) of the solenoid switch that is located under the big plastic "Mercruiser 8.1" cover, then under the EIM. If you're standing in between the engines facing aft, right at the diamond plate used as a step down, your port solenoid is just aft of your oil filter. Again, you have to take the black plastic cover off or take out two of the three bolts and rotate it around to get clearance to unscrew the nuts that hold the EIM down. I was a little nervous changing mine for the first time, but as long as you kill the power at the box on the bilge wall, you shouldn't have any concerns with shorting anything out. This particular solenoid should be available at your local marine store. I can get them from Aftermarket Marine down here for $14.95 all day.

I would TRY this, because the symptons that you are describing, minus the breaker tripping, are definitely symptoms of a faulty solenoid. I hope this helps ya buddy:thumbsup:

http://www.amarket.com/images/im106s.jpg
Click to expand...
Bruce,

Is there anyway you could tell me the part number of this solenoid. I'm having trouble locating it (not the part on my boat just the part number)
 
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