Voltage Regulator Test Sport Jet 90

[TOOSTROKIN]

Ok heres the deal. I finally found the firing problem on my 94 sport jet 90 when i replaced the stator. Fired up fine. Now it is not charging the battery. Volt meter reads 12.2 volts with motor off. After running a while with volt meter hooked up and about 4000-5000 rpm on the water no increase in voltage and actually starts to drop in 10-15 minutes to around 11.7 volts. Is there a test for the voltage regulator operation? Thanks.

 

[kenimpzoom]

Re: Voltage Regulator Test Sport Jet 90

http://www.geocities.com/kenimpzoom/KensSeaRayder-SportJet90.html <br /><br />Did you check the ohms on the yellow wires on the stator. I doubt it is bad, but try it just in case. It should be 0.6-1.1 ohms yellow to yellow, infinite to ground (my stator has zero ohms and charges the battery fine, but my meter may not be that accurate).<br /><br />As for the voltage regulator:<br /><br />1 Ohmmeter on R x 1 scale<br />2 Disconnect all regulator wires<br />3 Between red wire and either yellow wire, should be continuity connected in one direction, and no continuity when the leads are reversed.<br />4 Repeat with other yellow wire should be continuity connected in one direction, and no continuity when the leads are reversed.<br />5 Between either yellow wire and the reglator housing, should be continuity connected in one direction, and no continuity when the leads are reversed.<br />6 Repeat for the other yellow wire<br />7 Between the two yellow wires, should be continuity connected in one direction, and no continuity when the leads are reversed.<br /><br /><br />Be aware that I tested my voltage regulator and the reading were confusing, but it still works fine.<br /><br />Ken

 

[TOOSTROKIN]

Re: Voltage Regulator Test Sport Jet 90

Thanks i will try that now. Will let you know what i find.

 

[TOOSTROKIN]

Re: Voltage Regulator Test Sport Jet 90

Ok. Here is what i got. I started the test with the stator check. I have what appears -0- ohms between the yellow wires from the stator. Shows a dead short. ohm meter buzzes when i connect it to these yellow wires. I tried the voltage reg test and could get no continuity from the yellow wires to the reg housing and no continuity between the regulator yellow wires either. Now im confused. Should i have voltage on the two yellow wires on stator while cranking. If so what should the voltage be while spinning over.

 

[Capt Ken]

Re: Voltage Regulator Test Sport Jet 90

Lets make this simple. With the engine running, you should have somewhere in the 20's Volts AC between the yellow wires coming from the stator. Noticed I said AC not DC. Stator produces AC voltage. If the voltage is not there, then the stator is bad, if the voltage is there, regulator is bad. Simple, easy!!!

 

[Capt Ken]

Re: Voltage Regulator Test Sport Jet 90

BTY, after reading all your posts since last month, just remember, the two most common problems with these units are failure of stators and failures of rev limiters. Rare for the CDI's and trigger assembly to fail. Have had a 90hsp 94 Sport Jet in the boat stable for several years and just put a 120 in one last week and test ran it yesterday. Big difference in power.

 

[TOOSTROKIN]

Re: Voltage Regulator Test Sport Jet 90

Yea I have heard there is a big difference in the power of the 120 upgrade. Btw did you have to change the impeller? Back to the stator test. I do have voltage on the stator across the yellow wires. At cranking around 25 or so. Running it goes up to 60-70 volts at 4000 rpm. Thats AC voltage. So i guess the stator is operating properly. I am going to replace the regulator monday. Thanks.

 

[Capt Ken]

Re: Voltage Regulator Test Sport Jet 90

The boat I repowered was already a 120 so hopefully it was already a 120 jet. Now it was orginally a 90 but they had a bunch of problems when it was new so the dealership installed a 120 and replaced the engine hatch. Now did they install a different jet? Who knows!!! The boat I picked up for almost nothing and the new block assembly came from E Bay.

 

[kenimpzoom]

Re: Voltage Regulator Test Sport Jet 90

I think you have to change out the gears to convert to a 120. The swap would fit, but you wouldnt get any higher top speed cause the 120 would just hit the rev limiter. But the holeshot would improve dramatiacally.<br /><br />I honeslty think you could buy a boat with a 120 cheaper than you could convert your 90.<br /><br />Ken

 

[highaltitude]

Re: Voltage Regulator Test Sport Jet 90

have you checked for the recall on that ignition system

 

[funpilot]

Re: Voltage Regulator Test Sport Jet 90

If I remember correctly, the impellers on the 90 and 120 are the same, but the gearing is different.<br /><br />The 90 is geared 1.14:1 and the 120 is 1.0:1.<br /><br />good luck,<br />funpilot