mikea

So, this weekend I had a chance to take a ride and I was excited when the boat started right up. I went for a ride across the lake, a couple miles and stopped at the beach area. Threw anchor, unloaded the people, the chairs, and other stuff - and sat down for about an hour.

Got a call to head back for a couple more friends, tried starting the boat and .... nothing.

Turned the key and nothing, no starter motor. It seemed like the battery wasn't charged enough to turn it over - or something? I checked if I had left anything on (blower, lights, radio) and nothing was left on.

I got a friend to give me a jump and although the starter motor turned over, the boat wouldn't start?
Oddly, the starter motor didn't sound like it was making the engine turn over like it normally does.

I got a tow back to the dock and pulled the battery to get it charged up, but back at the ranch the battery appeared to be fully charged.

Not sure what the heck is going on. I imagine that the ignition switch, neutral position switch, and fuse are all okay, because the starter did turn over with a jump. (even though it didn't start the boat)

Perhaps, the starter solenoid is shot?

I'll go through the various tests shown in the manual, next weekend - but, I wondered if anyone else had experienced this type of failure in the past. Started right up on the first try, then an hour later - nothing.

I own a 2000 Seadoo Challenger 2000 – Sport jet M2 engine code shows it is a 2001 Model. Bought it new in summer of 2000, and have enjoyed it every summer up until this past year.

In the spring, I put the Seadoo Challenger in the water for the 1st time discovered a couple of things I wasn’t too happy about. The fuel gage wasn’t working and the boat smoked a lot more than it normally did over the previous 10 years of use. I figured I needed new plugs and a tune-up – but, had no idea why the fuel gage stopped working. I checked all the standard stuff that was easy to look at, but nothing stood out as a problem.

So, I put the boat on the trailer and took it to a local mechanic (said they were recent students at the Mercury Certified Mechanic school). After a couple of weeks , they contacted me and said I had to replace the fuel sending unit, in order to get the fuel gage to work. They replaced the fuel filter, replaced the spark plugs, and checked the timing (which was within spec). They also said that the Air Temp Sensor wasn’t working properly, and that was why the excessive smoking. The ECM was taking the air temp from the sensor and adjusting the oil/fuel mixture so that it was very rich (due to the air temp registering as though it was freezing outside). After waiting another week for them to get the fuel sending unit and air temp sensor, I gave up and told them I couldn’t wait much longer – and that I was buying the parts and bringing them over on Saturday for them to finish the repair.
When I arrived on Saturday, one of the technicians was no where to be found, and I got a call from the other telling me there was an emergency with his fiancé and he couldn’t be there. I located the other technician only to be told that he had to stay by the boat Fuel filling station, and that he couldn’t work on the boat either. I asked where my trailer was parked, and if I could borrow a screw driver and pair of channel locks. He said yes, got me the tools and the boat trailer. I installed the air temp sensor and the fuel sending unit myself in just under 1 hour – took the boat for a ride, and it started right up, the fuel gage worked again, and it ran great. Loaded the boat on the trailer, paid the bill, and left.

After a few rides, the rough idle returned at low end (in neutral throttle position). I did a lot of investigation online, and reading forums, and ended up replacing both the Engine Temp Sensor and Engine Temp Sender, located on either side of the engine block, hoping to improve the cold start low idle and smoking situation. The boat started right up, and didn’t smoke nearly as much, although the low idle was still too low (at about 700 rpm).

The initial ride went okay, but the next day on the return trip back to the dock, the boat wouldn’t go faster than about ½ the normal WOT speed. (5 weeks later, I found out that the ECM decided to save me, by putting the engine in the safe operating mode).

Fearing the worst, and not having the tools to correctly diagnose the situation, I began looking for a mechanic that had the proper equipment and I was determined not to go back to the guys I initially went to that couldn’t find the time to order the parts, let alone install them in a timely manner.

Totally frustrated at this point, I loaded the boat back on the trailer and took it to another mechanic that was recommended by my neighbor. I called and he said he was Mercruiser Certified, had a computer that could read the ECM, and he could look at the boat a couple days. He told me, that after that he would call me to tell me what he thought was wrong and how much to fix it.

After a week, I called him to find out that he had not gotten to it yet. He promised to get to it the next day, and he would call as soon as he knew what was wrong with it. A week later, I called him again. He said his technician took the boat out and agreed that something was definitely wrong. I asked if he could hook up the computer to the ECM and see if that would tell him anything. He said the technician had tried that but the computer wouldn’t read the ECM. I asked what he thought was the next steps then? He said he needed more time to diagnose the problem. I asked him to call me in 3 days. He called 3 days later, and he said the technician thought the ECM was bad, or one or more Igniters weren’t working because the engine seemed like it was only running on some of the cylinders. I asked if he had checked the Stator and the Trigger. After waiting all this time for the boat to get fixed, I had a lot of time to research and read about the all the problems people reported on the 240HP EFI Sport Jet engine. It was my opinion, that after not being able to read the ECM – all the technician was doing was guessing – the same thing I would have been doing. This was turning out to be a nightmare.

The next day I got a call telling me that the Trigger was not testing to the spec listed in the service manual, and that I should replace it. The Stator tested out as a good part. The igniters that were thought to be not working were okay after all. I verbally approved replacing the trigger, hoping that was what was wrong. That next weekend, I showed up to pick up the boat only to find out that the new trigger did not fix the boat, and that they had given up trying to figure out what was wrong.
The owner and technician said that this was the first boat they ever worked on that they couldn’t figure out what was wrong – the first time ever. I asked him what he would do if he owned the boat and the Certified Mercruiser repair guy told him that he could NOT figure out what was wrong with it? He told me, he would take it to the largest Seadoo dealer in the state, because they would be the only ones that might be able to figure out what was wrong. After searching for 45 minutes for my boat cover (which they never found and claimed I never left it with them), I paid the bill, hooked up the trailer, and left – very disturbed and upset.

I started calling around and researching, where I could go next.
Who could help me? Seadoo dealer I bought the boat from was no longer in business. Seadoo was no help at all and couldn’t even provide a phone number to Mercruiser. I tried contacting Mercury Marine directly in Wisconsin and was unable to get anyone to help diagnose the problem, or recommend a service provider. I guess the boat was too old and no one much cared anymore because it was no longer under warranty.

While thinking what my next move would be, I continued to research online and I came across a story about someone that had replaced a part with another bad part. Apparently, that possibility does occur and I hadn’t thought about that as possibly being the problem – up to then.

While researching more online, I also came across a diagnostic device tester that could read trouble codes. This company also sold a software package that could be loaded on your laptop, hooked up to your ECM, and you could diagnose various engine sensor readings. It was expensive ($500), but if I was going to keep the boat - I figured I better be able to diagnose and fix it – since I had yet to find anyone that demonstrated that they could do either.

Knowing that the last thing I did was replace the 2 engine sensors, I back tracked and replaced the Engine Temp Sender with the previous one that I had taken off – and lo and behold - it fixed the problem. The boat was no longer stuck in safe mode.

The engine started and ran like it had before, except the low idle was still @700 rpm.

I had read that the Throttle Position Sensor adjusts the oil mixture richness for cold starting. I hooked up my Diacom tester to the ECM, and read the idle speed and Throttle Position Sensor resistance. I adjusted the Throttle Position sensor by loosening the 2 mounting screws, and rotating it from the existing position. That brought the low speed cold idle up to 950rpm, and it sounded and idled much, much better with far less smoking.

The Diacom tester showed that the Throttle Position Sensor went from 0.04 volts to .22 volts – as I rotated it within the slot limits. I set it at .2 volts as indicated in the Service Manual. According to the service manual the lower the voltage value the leaner the engine will be running, and the higher the value the richer it will run. The odd thing was that the Throttle Position Sensor value changed as I rotated it only for a small part of the angular rotation, then it level off (didn’t change any more). I thought that this Sensor was like a potentiometer, and it should continuously increase or decrease in value as it is rotated with the limits of the slot.

I was concerned that the Throttle Position Sensor may not be functioning correctly, but I wanted to see if that adjustment made any difference in the idle and smoking. The boat started up nicely, idle was great, engine sounded good, and the low idle start up smoke was reduced.

I checked the oil tank level and saw that the large reservoir at the bottom of the boat, was a little low, so I unscrewed the cap and filled the reservoir, and screwed the cap back on.

Went for a ride and noticed that the small LED light on the fuel gage was blinking, ever so dimly, while speed was low. Then, as I increased the speed the LED light blinked faster and faster – brighter and brighter, then the alarm horn started beeping. That was a first time event. Never had a blinking light before.

Went back to the dock and reset the throttle position sensor back to where the low idle and smoking location was at (I had marked the location with a paint pen, just in case) – and took the boat back out.

The LED light didn’t blink and the alarm horn didn’t go off – but the engine idle seems way too low and the smoking exists. The spec says it should idle around 1000rpm.

I read that the alarm could be set off by the float in the small oil reservoir on the front of the engine. That makes sense; if the oil level gets too low the float would set off alarm and warn you to put in more oil. With the key on and engine running, I unscrewed the filler cap, and moved the float on the stick until the alarm horn went off. The float switch works, and the float works. It didn’t go off when I put it back in the reservoir and screwed the cap back on.

I also read that you need to be sure the caps are seated properly, and that you may need to bleed the air out of the system. I didn’t do that – didn’t know how to until I read the repair manual that I just purchased. I will consider that in the spring, because that was the last thing I did this year - before prepping it for winter and putting it away.

It has been a hell of a summer for boat problems. Glad to get away from it for a few months. Actually started thinking about selling it, which I really don’t want to do – especially once I get it fixed and running right again. But, this summer has got me worried about being able to get reliable replacement parts. The boat is going on 12 years old next year.

I’ve been thinking about what I should do in the spring. A replacement Throttle Position Sensor runs around $475 – which I don’t want to buy if I don’t need it.

The mechanical idle adjust position was set at the factory, and I have never touched or adjusted it. I wonder if I should just adjust that, and leave the Throttle Position Sensor alone?

I wonder if the oil alarm and the low idle are related.
The Throttle Position Sensor adjustment sure seems to have been the link between those 2 things happening.

Got any ideas?