1987 Yamaha 200 no power

avt13

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I have a 1987 200 yamaha that came on a boat I just purchased. The problem is no power. It won't go over 1400 rpm. I have changed the anti-siphon valve,drained the fuel tank, new fuel line from the tank on, new fuel filters,new fuel pumps, new spark plug boots,new plugs,and rebuilt carbs. I also bypassed the filters, primer bulb and motor connector. It starts OK and idles well. Tried the choke at open throttle and it wanted to die. I checked the spark and it seemed OK(jumped a 1/4" gap)except for all cylinders it cut out for about 3 or 4 seconds then would resume. Tried to disconnect the ground to the control unit to see if that would help and no joy.Any suggestions?
 

avt13

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Re: 1987 Yamaha 200 no power

Well I am still trying to chase down this problem. Any suggestions?
 

rodbolt

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Re: 1987 Yamaha 200 no power

test the compression. if that is ok you will need a peak reading multimeter to further test the ign. the 200 should not have cut spark on any plug. it was desined to operate on all 6 all the time. you may haave some ign issues.
 

Ray Neudecker

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Re: 1987 Yamaha 200 no power

Disconnect the white wire from the control unit to the CDI unit to be sure the control module is not the problem.
 

avt13

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Re: 1987 Yamaha 200 no power

I tried disconnecting the white wire and it didn't make any difference. I also tried to check the cdi with 3 different vom and couldn't get anything that looked like it should according to the manual, but I don't know if that is the cdi or the testers problem.
 

Ray Neudecker

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Re: 1987 Yamaha 200 no power

As Rodbolt said test compression first. If it is okay then start looking for an electrical problem. CDI failures for that model are extremly rare. The fire should be continous unless you have an electrical problem. Not sure there is any way to actually accurately test the CDI itself for the problem. First be sure that all of your ground connections are good with no corossion. Then test the stator and lighting coil with an ohm meter. If they test good that way they are normally ok. Unless you have a connection problem if it fires at idle it will continue to fire at higher RPM's.
 

avt13

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Re: 1987 Yamaha 200 no power

Well I finally got the time to check some things today. The compression runs 105-115 all cyl. I also swapped out the CDI and the control unit with known good units and have no change. I then checked the trigger and pulser coils and they are OK. I am beginning to wonder if a) there is no spark issue at all b) perhaps I didn't do the carbs properly.<br />when I rebuilt the carbs, my chiltons doesn't give the float setting for the dual float carbs so I set them at what I thought was close to what they were before. A very real possibility exists that I missed the mark on them. Supposedly this thing ran fine before it sat for the better part of a year so the carbs would have to be the first guess. <br />I really appreciate all the help you guys give, not only to me, but everyone else too.
 

rodbolt

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Re: 1987 Yamaha 200 no power

have you tested compression? also test the high speed charge coil. it should not have cut out the spark on any cyl during any testing the control unit, CDI, must remain grounded. does the audible alarm horn work? the white wire on the CDI is the kill circuit wire and may be removed for testing. be aware that engine shut off is almost impossible with the wire off.
 

avt13

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Re: 1987 Yamaha 200 no power

Yes, I have tested compression 105-115 all cylinders. alarm horn works, tried disconnecting the white wire, even tried a different control box with no improvement.I tested all the coils I could, all OK. Do you happen to know the float setting for the dual float carbs?
 

easygo0

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Apr 4, 2004
Messages
59
Re: 1987 Yamaha 200 no power

I belive 16 mm or 0.63in between float top to mixing chamber gasket surface is in range that would be needle valve in closed position that is from my yamaha 89 manual should be real close if not the same,make sure all air and fuel circuit passages are clean small strand of wire works for me .good luck
 

Ray Neudecker

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Re: 1987 Yamaha 200 no power

Seems time to try again on the carbs. When you have the carbs apart hook a piece of water hose to the intake and raise the water pressure until a stream is coming out of the seat about 12 inches. Shake the carb around. If at any time the stream deflects to the side, you still have a restriction there. More cleaning and blowing out with air until it does not deflect.
 

avt13

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Re: 1987 Yamaha 200 no power

Thanks guys, I will go to the carbs again! I appreciate all the help.
 

avt13

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Re: 1987 Yamaha 200 no power

OK so it took me a while to get to it but I finally got back to the carbs and what do you know, the top carb had some crap in it that was not visible at first look. Cleaned it again and now it runs good!<br />Thanks for all the advice.
 
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