1998 SeaDoo Sportster 1800 Elecrtical Questions

[cmhaagva]

Bought this boat with a blown engine. Worked thorough those issues. Had the boat out a few times.

Holy S... This things moves!!

The Speedo, fuel gauge do not work at all. Oil LED is intermittent. Sometimes it on, sometime not. Half tank oil. (oil level is fine, ALL lines replaced and bleed which should have no effect anyway)

I am a seasoned field service technician for large CNC and laboratory equipment. I know how to read a print and a DVM.

I have tried the obvious, jiggle all of the connections and look for corrosion on connections, loose/broken wires in the harness.

I have a print for the boat that I can read and understand.

Before I start Ohming out wires and spending money on replacement components, are there any ways to test if the components have failed? The wiring harness in general looks good. Resistance readings for the sending units, proper voltage, etc?

Are these variable voltage or grounding units? The manuals/prints are a little vague. Are there any common failure items? The Tachs on both engine work fine. All of the gauges have cracked lenses.

I see most things run through the MPEM but suspect these issues are outside the influence of that component.

Detailed suggestions appreciated.

Thank You.

 

[Dr Honda]

First... Welcome to our forum.


OK... it always helps when the person working on the boat knows how to use tools. So, lets start at the beginning.

1) The "Oil" light on our boats is kind of dumb. it will illuminate with other issues. (like an over temp)

2) Does your buzzer work? It should sound when the light comes on.


The reason I ask about the buzzer, is it can help with knowing what is tripping the alarm. Also... when you see the light come on... is it in any special condition? (bouncing, full throttle, so on)

Generally, if the oil tank is half full... your low oil warning shouldn't sound. But, those senders do go bad once in a while. SO... since you know you have oil, I would short the wires together right at the oil tank, and see if that makes the light go out.

 

[cmhaagva]

Dr Honda

Thank you for the input.

I am un-familiar with the expected behavior of the buzzer. From what I read, it does not seem to respond the way the manuals describe that it should. Sometimes I insert the DESS and have two clear beeps. Other times nothing. The boat always starts.

I took the boat out three times and the oil light would come on briefly during some of the rides but no beeps. This last time out, I was running a river with a current. Went down stream, the oil light would flicker on and stay that way for awhile. No sounds . Then it would go out. Off and on for awhile. Went back upstream and the same thing. Never seems to be related to fast, bumpy or slow. As I was pulling the boat to the ramp (bout 1 1/2 hours run time), I got a fast beep, beep, beep. I was under a bridge with moving water, 2 kids and trying to get the boat to the ramp. I do not remember if the light was on. Just got close and pulled the lanyard. Sound was not present when I plugged it in later.

It has been raining here so I have not been able to get more specific info. Will do this weekend.

 

[cmhaagva]

Dr Honda,

I thought I would start by trying the obvious, I added oil to the tank...and went on a 5 hour ride with no alarm. In retrospect, the tank was closer to 1/3 full than 1/2. Still I was nowhere near danger of running out of oil. Guess the sensor reading level is a little higher than I expected.

Moving on the fuel sensor--can I ohm it out o see if it is working?

Is the speedo sensor a magnetic pickup?

Do these gauges normally fail?

 

[cmhaagva]

Update

I was able to find information on testing the fuel sensor in the addendum to the service manual.

The sensor tested dead. Installed new $250 sensor and the fuel gauge is working.

Tested the magnetic pickup on for speedo and found no voltage. When I removed the sensor from the boat the potting was cracked. Replaced sensor and tested prior to installation and found a variation in voltage as it should do. Installed in boat and found no reading on the Speedo. Checking part numbers I found that the incorrect speedo was installed in the boat. Ordered a replacement Speedo.

Will update as things progress.

 

[Dr Honda]

Let us know how the new speedo works out.

 

[cmhaagva]

Let us know how the new speedo works out.

Installed the new Speedo and had the boat out yesterday. It works great. I am guessing that someone swapped the original Speedo when there was a problem and gave up when that did not fix the problem. I have included the tests I used which were copied from section 9 of the wiring/addendum for this boat. The oil sensor checked out OK when I tested it.

FUEL LEVEL RESISTANCE
mm (in) (W)
full 299 and more 11.8 and more 0 ± 2.2
7/8 272 @ 298 10.7 @ 11.7 17.8 ± 2.2
3/4 247 @ 271 9.7 @ 10.6 27.8 ± 2.2
5/8 220 @ 246 8.7 @ 9.6 37.8 ± 2.2
1/2 194 @ 219 7.6 @ 8.6 47.8 ± 2.2
3/8 162 @ 193 6.4 @ 7.5 57.8 ± 2.2
1/4 130 @ 161 5.1 @ 6.3 67.8 ± 2.2
1/8 86 @ 129 3.4 @ 5.0 77.8 ± 2.2
empty 0 @ 85 0 @ 3.3 89.8 ± 2.2

To verify speed sensor, use a voltmeter as follows:
– Disconnect speed sensor from inside the bilge.
– Provide 12 Vdc to the sensor. Connect the +
wire to the PURPLE/YELLOW wire and connect
the - wire to the BLACK wire.
– Connect the voltmeter (+) probe to the BLUE/
PURPLE wire and the (-) probe to the BLACK wire.
– Slowly turn the paddle wheel. You should read
a voltage variation with the voltmeter.

I also took the time to install a Humminbird HDR 650 depth sounder. I potted the transom mounted transducer on the inside of the hull, on the flat spot, next to the bilge pump because I did not want it hanging off the hull risking damage. This is also the lowest point when the boat sits in the water. After cleaning the spot thoroughly with Acetone, I used polyester fiberglass resin mixed with a small amount of glass microballoons to make a runny paste then added enough hardener to cure at a slow rate. It worked very well. Much to my surprise, the deep water everyone is running at top speed averages 2-4 feet. I did several checks by dropping the anchor over the side. It takes accurate readings right up to a foot below the keel which is exactly what I wanted it for.