Merc Sportjet 120 No spark

[jetdriven]

Re: Merc Sportjet 120 No spark

Since you have a digital meter, it should read correct voltage on the 0 to 750 scale. I think the stator is bad. You're welcome for the help. Good luck.

 

[clanton]

Re: Merc Sportjet 120 No spark

You need a peak reading meter to check stator output, regular meter reads low. Trent can tell you how low. You say you are checking green/yellow and yellow/green leads. I have a red stator in my hand has 2 yellow wires, 1 green/white, 1 white/green. Merc manuals I have looked at do not show green/yellow, yellow/green. The first thing to check is the stator output with wires disconnected. Connect the meter leads between the 2 wires, close to 100 volts at cranking rpm with peak reading meter.

 

[tonym302]

Re: Merc Sportjet 120 No spark

thanks clan. It may be white with some grime on it. but it is the red stator.<br /><br />what kind of meter do i need to test this? what should the readout be on a regular meter?? <br /><br />and do i have to disconnect the yellow wires when i test it??

 

[clanton]

Re: Merc Sportjet 120 No spark

Only disconnect the 2 wires you are testing. The 2 yellow wires are for charging the battery. Watch my post on peak reading meter, Trent will post numbers to convert AC readings to peak meter readings.

 

[clanton]

Re: Merc Sportjet 120 No spark

Muitiply the AC reading by 1.414 this should be close to what a peak reading would read.

 

[jetdriven]

Re: Merc Sportjet 120 No spark

Hey Tony,<br />If you still have the manual that came with your digital meter, it will tell you how to calculate the ac voltage riding on a dc circuit. If you look at the equation, you'll see where that factor of 1.414 is coming from. So, if your stator was good, you should be reading about 120-130 volts on your meter. <br />I think you've got a baked p-stator!

 

[kenimpzoom]

Re: Merc Sportjet 120 No spark

If you have only 16 volts out of the stator, it is dead or the magnets in the flywheel are messed up.<br /><br />Have you checked the resitance between the wite/green and green/white wires? That should give you a good indication of stator condition.<br /><br />Ken

 

[tonym302]

Re: Merc Sportjet 120 No spark

i turned my meter to ohms and with nothing attached, it reads 1.0 i hook up the green and white wires and the readout doesnt change. does this mean there is no resistance in it?? <br /><br />Another question, how the hell does this flywheel come off?? i tried a puller with a lot of force with zero luck.... i tapped the center bolt and still nothing.... any tips?

 

[kenimpzoom]

Re: Merc Sportjet 120 No spark

To test the ohm meter, turn it to ohms and without touching the leads together it should read infinate ohms. If you touch the leads together it should read zero ohms.<br /><br />Now put one lead on the green/white and the other lead on the white green and it should be about 600-800 ohms. If it reads 1 ohm, the stator is fried.<br /><br />As for the flywheel, jetdriven can help more as he had the same problem. I think he got his off by tighntening up the puller, use a prybar to gently pry up one side, and then LIGHTLY tap on the big bolt on the puller. Dont hit too hard or you will destroy the bearings.<br /><br />What is too hard???? I dont know.<br /><br />Ken

 

[tonym302]

Re: Merc Sportjet 120 No spark

thanks ken, can i whack it with a 5lb sledge?? This boat is starting to really test my patience!!

 

[kenimpzoom]

Re: Merc Sportjet 120 No spark

I ve wanted to sledge-o-matic my Sport Jet many times!!!!<br /><br />Have you looked at www.sportjetworld.com for any info. They have a forum dedicated to our beloved Sport Jet.<br /><br />Also, jet driven and row home on this board have Sport Jets.<br /><br />Good luck, Ken

 

[jetdriven]

Re: Merc Sportjet 120 No spark

The flywheel...I used a harmonic balancer puller with Grade 8 bolts screwed into the flywheel. The bolts that come with the pullers are not strong enough. I tightened the center bolt of the puller with an impact wrench to about 250 ft-lb of torque. Even all this force may not be enough to break it free. Striking the puller bolt was the only way that I could get my flywheel off. This a desperate act and is never a good idea. Striking the bolt alone did nothing for me. Somewhere on this forum I read that someone used a prybar to lift one side of the flywheel while striking the puller's center bolt. The force of the prybar with the striking did it for me. I put a very thin coating of anti-sieze lubricant on the shaft before reinstalling the flywheel. You need to torque the flywheel nut to 90 ft-lb.

 

[tonym302]

Re: Merc Sportjet 120 No spark

jet, i will give it a try tomorrow. so air gun it to 250, pry one side, then whack the center bolt?? thanks guys...

 

[wakataka]

Re: Merc Sportjet 120 No spark

Tony - <br />I got mine off (after several hours) using a harmonic balancer puller with grade 8 bolts, penetrating oil, a propane torch, and finally a hammer. It was a real struggle. I tightened the puller as tight as it would go, filled the "well" in the flywheel center with penetrating oil, and let is sit for about an hour. When it still wouldn't budge, I gently heated one quadrant near the center of the flywheel with a propane torch. You don't want to overdo it and cook the stator, but the heat can help draw the penetrating oil into the joint and also, if you heat on one side only, it will tend to expand the diameter of the center hole. After three tries with heating, tightening, oiling, and waiting, it still wasn't coming off. I finally had to hit the top of the puller with a hammer. I used a 2 pound ball peen and hit it rather gently. About 4 blows did it. I understand that you can damage the bearings if you whack it too hard. Good luck!

 

[tonym302]

Re: Merc Sportjet 120 No spark

OK, I hate to resurrect an old topic, but I finally got the flywheel off. Stator magnets were all rusted and had shavings/junk on them. plus teh magnets on the flywheel detached and were stuck on the stator. I replaced the flywheel and tried for spark. Nothing. I checked the volts across the gree/yellow wires from the stator and got only 64-68 volts while cranking the motor. Someone commented that it should be like 150-180. I also checked the resistance between the stator wires and the meter showed no change from when the wires were disconnected (infinite??) <br /><br />I assumed the stator was no good and ordered a new one today. <br /><br />Comments?

 

[jetdriven]

Re: Merc Sportjet 120 No spark

I think that you need a new stator. The voltage reading with the new stator on a regular voltmeter should be about 120-130, or 180 on a peak reading meter. <br /><br />Good luck.

 

[tonym302]

Re: Merc Sportjet 120 No spark

Ok guys, I received my stator. and it has 2 yellow wires, 1 red/white stripe and blue/white stripe bound together with a 3 cyl label on it. Then there is a solid blue, and a solid red. see pic<br /> http://www.mustangmods.com/data/2200/dsc00008.jpg <br /><br />On my red stator, I have the 2 yellows. Ok, now the issue, I have 2 greens (solid and white striped) that plug into 2 more green wires that run into what appears to be a regulator/rectifier/ballast of some sort. Opposite end of thie regulator box, a blue and blue /white striped wire connect to a blue and blue/white wire on the main ignition box.<br />see pic. you can folow the blue wires back to the regulator box.<br /> http://www.mustangmods.com/data/2200/dsc00007.jpg <br /><br />Can I unplug the regulator box thing and just hook up the 2 yellows, and 2 blue wires?? Cuz the blue and blue/white striped matched up to the stator. I bought the stator from SeilerMarine.<br /><br />See the pics linked.

 

[jetdriven]

Re: Merc Sportjet 120 No spark

This stator http://www.mustangmods.com/data/2200/dsc00008.jpg photo isn't a red stator. Is this your old stator? If it's your new one, it looks like it works like the original black stator did, that is, without any type of adapter. The red stator needs an adapter to go between the switchbox and the stator. Sorry, I'm a little confused about whether you have a red merc stator or a new black aftermarket stator.

 

[kenimpzoom]

Re: Merc Sportjet 120 No spark

Are you sure they gave you the correct stator? I would ask SeilerMarine about it. I have asked them several questions and they quickly answered them.<br /><br />Red stators by Mercury only have four wires (two yellows, one white/green stripe, one green/white stripe).<br /><br />Not sure about the CDI/Rapar stators you have.<br /><br />Regards,<br /><br />Kenneth Oyler

 

[tonym302]

Re: Merc Sportjet 120 No spark

Thanks guys, I have a red stator in there now, and this is the one that I think is faulty. I ordered a new one from Seiler and the one in the pic is what I got. <br /><br />Hey Jet, can I take that adapter out of there and just run the blue wires together, and the yellows?