150 merc. high speed miss & bogdown

[power-manager]

I have a 1983 150 Merc. V6.Worked great 2 years ago, didn't use last year. Took it out this year and could'nt get above 2000rpm under load. Tore down carb's, they were very clean but flushed all passages anyway. Also changed spark plugs. Now I get up to 2700-3000 rpm and high speed miss. Timing light,in fresshwater tank, appears to be missing on all cylinders equally at high RPM ,no load, although may be measurement error.Any ideas?

 

[clanton]

Re: 150 merc. high speed miss & bogdown

You need peak reading meter or meter with DAV function to check stator and switch box output.IF you think fuel check main jet holder,just looked at one where the main jet holder was tighten so much that the holder was twisted and closed off the holes that feeds the main jet.

 

[power-manager]

Re: 150 merc. high speed miss & bogdown

Thanks for the feedback.I don't think it 's fuel because I was very careful in checking and reassembling all the carb's.Someone else mentioned the stator also. there is a low speed and high speed winding?Any idea how to check? Which wires, voltage level etc.

 

[clanton]

Re: 150 merc. high speed miss & bogdown

Stator low side red lead to blue sw box termial, black lead to ground, scale x 10 300/1000 rpms volts 210-310. 1000/4000 rpms 190/310 volts.<br />Stator high side red lead to red sw box termial, black lead to ground, scale x10 300/1000 rpms 20-100 volts. 1000/4000 rpms 140-310 volts. Output to coil red lead to + termial, black lead to - termial 1000/4000 rpms 180-280 volts. These specs are for peak reading meter or muiltmeter with DAV function<br />or adapter<br /><br /> This info came with a DAV adapter.

 

[hondon]

Re: 150 merc. high speed miss & bogdown

Take a very short and pain free look at the anti siphon valve on this thing. WHO KNOWS?Could be?

 

[power-manager]

Re: 150 merc. high speed miss & bogdown

Well,I finally fixed this thing. It turns out it was the stator. At high RPM the voltage on on of the high speed windings would actually go down with speed. I assume it has some shorted turns,probably from water geeting in there over time. Thanks for all the help, it was a dog.