Finally pulled my head..top cylinder ate a ring

[pnwboat]

Looks like the high speed winding is a bit out of tolerance but, keep in mind that the voltage will increase with RPM's. If your looking at documented voltage levels based on a running motor between 1000 - 4000 RPM's and checking them at cranking speed, your readings will be lower.

Try checking the stator charging voltage by putting the meter leads on each of the Yellow wires. The Red Positive lead on one Yellow wire, and the other Black lead on the other Yellow wire at 2500+ RPM's.

Standard torque value for the exhaust cover bolts which I believe are 1/4 X 20 is 8 FT LBs.

Are you sure your replacement tach is working? Try switching the selctor switch on the tach to a different setting and see if it starts to work.

 

[scout-j-m]

I'm glad you caught that. I actually did do the stator voltage test while running the motor. I stuck cranking in the label from habit of all of the other checks. For both windings I checked voltage at about 1200 rpms and throttled up to around 2500 while watching the meter. I will need to recheck but I think th low speed voltage stayed constant with the rpm increase and the high speed actually dropped some.

I believe I checked the stator charging leads as you mentioned and got the same reading as the other ways. As to the tach, I can't verify it is working since my old tach didn't work either. I bought this one in the spring New though. I can try changing the pole setting on the back to see if that helps.

 

[scout-j-m]

I rechecked the stator voltage output today. I had the motor idling at about 1200 rpms and the low speed voltage was the same as I previously posted. The high speed was also similar; maybe a few volts more. I gradually increased the rpm's and tested each winding again. Both voltages climbed although the high speed winding didn't get to the 130V minimum until about 2000 or so rpm's.

I rechecked the stator charging windings again as well. I tested as suggested with one of my meter's leads connected to each yellow stator wire and saw like 1. something volts at both idle speed and at 2500-3000 rpms. I also rechecked testing each lead to ground at both speeds and saw similar results. I then tested my meter on my lawnmower's stator output wire and saw 80V AC so I know that my meter is working properly when set on AC voltage. So I guess the stator charging winding is shot.

At this point, I am not sure what to do. Do I replace the stator since the high speed winding voltage is out of spec at lower rpm's (although still in the rpm range where it should still show a minimum of 130V) and since it doesn't appear to be producing any charging voltage? Or do I replace the switch box since it failed the bias test???? If both need replacing it is not an ideal situation, however, since this is a rebuild I want everything done right so it's not going to make me angry if I have to do so.

Oh, and as to the exhaust cover leak...I had torqued the bolts to 70 in lb per the factory manual. I bumped all the reachable bolts up to 100 in lb as suggested and still had leakage. Then bumped them to 120 in lb, which was as high as I was going to go, and still had leakage. I then removed as many as I could reach to get the top area to separate some and it doesn't appear the outer gasket is present. Don't see how I could screw that up but looks like I may have. If I can find the appropriate tools to get those bottom 4 or so bolts out then I can remove the cover and hopefully fix it.

 

[pnwboat]

Well at this point, you've pretty much verified that the battery charging winding in your stator is not working. Based on that, I would start by replacing the stator. Once that's done, re-check the Switch Box. If it's checks within tolerance, you should be good to go. If still not within tolerance, replace it.

 

[scout-j-m]

Thanks. I'm going to order the appropriate CDI Electronics stator today. Looks like the going rate is anywhere from $200-225. Hopefully shipping is fast so I can get it installed by the weekend and in the meantime I can work on that exhaust cover leak. If I get that squared away and am still waiting on the stator I may try to post a video of it running. When it's running on all cylinders, it sounds like a champ. Nice and smooth at 1100-1200 rpms in the tank. Even when it loses the top cylinder it's runs surprisingly good.

 

[scout-j-m]

I finally got the new CDI Electronics stator installed and fixed my exhaust cover leak. For the exhaust cover, I forgot the second gasket between the metal baffle and the cover! I have no idea how as I was always aware one went there.

As for the stator...I started and ran the engine for a fairly long while in a tub and never had the previous issue of the top cylinder losing fire. I have yet to do any tests on the switchbox to see if it now in spec but it is a good start.

The only issue now is that the new rectifier/regulator doesn't seem to be working. The tach still didn't work nor did I see any charging voltage. I tested the stator's yellow wires and saw 40V AC at idle speed and around 70V at fast idle when I connected my multimeter leads between them. Connecting each to ground didn't read anything. I tried plugging each one directly into the gray tach wire in the harness but got nada. Would I need to connect them together and splice that into the gray wire to get a tach signal? I think these cheaper rectifiers are just junk. I bench tested it when I got it and it failed the bias test. They sent me a new one which also failed the bias test. I haven't tried the newest one they sent on the motor yet though. Im hoping I can get a refund and then just go and buy the CDI Electronics one.

Either way, I am going to install my knockoff brand tiny tach this week and get in the water by this weekend. I'm really happy the way it runs in the tank, especially compared to prior to the rebuild. It starts so easy and runs very smooth. Hopefully it performs as well when under way on the water.

 

[pnwboat]

Well sounds like you are at least moving in the right direction.

Some of the aftermarket rectifiers have different wiring set up. What really makes it confusing is that the wire colors are the same as the original rect./reg., but they mean different things. Example.... the black is normally ground, but on some of the aftermarket ones, that is actually the "Hot" lead or the positive battery lead.

Good luck!

 

[scout-j-m]

I am going to diagnose it more when I get the chance. I need to recheck to see if I have continuity between the tach wire on the harness at the motor and the sugnal wire at the tach itself. I know power and ground is good at the tach since the backlight works.

Is there a way to test the tach whether it be a bench test or to hook it up to my mower or something just to ensure it is not a dud?

Also, since it didn't work when I connected the tach wire directly to either stator yellow wire I was wondering if the other yellow wire was supposed to be connected somewhere rather than just hanging. Possibly to ground?

 

[pnwboat]

I think that checking continuity of the tach wire from the motor to the tach itself would be a good starting point.

Not sure about bench testing the tach. I would imagine any small engine stator that has a battery charging winding will work. Just remember not to hook it up to the ignition system winding as this has high voltage and I'm not sure your tach would like it. You can google "bench testing a tach" and there are some folks that use a standard battery charger, but I would be hesitant of doing that. I would be more comfortable using say a D-cell or maybe a 9v battery just for a second or two instead and see if the needle moves at all. I'd hate to let the "magic smoke" out of my tach. LOL! If you know what I mean.

 

[scout-j-m]

Good news and bad. The bad is that the new stator turned out to have not fixed my loss of spark issue. I lost it this afternoon while running the motor for about 10 minutes doing rectifier tests. I didn't do another test on the switchbox but I guess now I don't have to. I'll order the new CDI Electronics box tomorrow and will probably go ahead and get a new trigger while I am at it. The trigger is cheap compared to the switchbox plus then I will essentially have a totally new ignition system to go with the rebuild.

The good is that the rectifier actually does appear to be creating DC voltage on it's red output wire. It was a little hard to do on my own but I was seeing about 13V at idle and about 13.5 at fast idle which was about 2000 rpms. The tach still didn't work though. I verified that the power wire and ground wires on the back of the tach were good but didn't get to the continuity test. I also verified that the tach was set on the 12 pulse setting (I'm assuming this aftermarket stator still produces the same pulse number?). I checked the AC voltage on the gray wire right where it comes out of the rectifier and saw 4 or 5 volts at idle. Seems low but I don't really know what I should see there.

 

[pnwboat]

Yes the replacement stator has the same number of poles (12) as the old one. You can also temporarily run a wire from the Gray wire on the Rect./Reg. to the tach, or do as you suggested and check continuity. Which ever is easier.

 

[scout-j-m]

I ordered the switch box and trigger late last night. Hopefully they will make it it by the weekend.

I also got home a little early today and I went ahead and checked the continuity of the tach wire. It did have continuity between the rectifier and the end at the tach itself. I then warmed up the engine and ran a jumper from the tach signal wire to one of the yellow stator leads and the tach worked! So it appears my rectifier/regulator is working to convert the AC to DC to charge the battery but the gray output wire is just dead. Not ideal but considering it was $35 I'll take it. I'll just tap into one of the yellow leads and tape off the unused gray wire.

I'll post back when I get the switch box and trigger on.

Edit: At least I thought it was creating DC voltage now. Just tried it and didn't have any luck. I think I screwed up my multimeter the other day though somehow. I'll just have to borrow one and retest.

 

[scout-j-m]

The new switchbox and trigger are finally installed. It was harder than I thought it would be because the new CDI parts have incredibly long wires (which is a good thing) and made it difficult to get everything connected and tucked away and also making sure the trigger rotated with causing its wires to contact the flywheel. I ran it on muffs and seemed to work fine and keep fire on all cylinders at all times. I also retested the rectifier/regulator and it does appear to be functioning correctly. I reved it up slightly and was able to get the voltage output to climb to around 13.3V (at 2k rpms maybe?) so hopefully at WOT it doesn't run up to some voltage that is out of spec and too high. The tach wire coming out of it still doesn't work though so I cut a yellow lead off of my old stator (remember the charging windings weren't working anyways) and am going to make an inline t-fitting to connect between the stator and rectifier and split a yellow lead up to the gray wire in the motor's wiring harness. I probably need to recheck my static timing but other than that I should be able to take it for a lake test and start the break in.

 

[pnwboat]

Looks like you're all set to take it out.....finally! Good luck.

 

[scout-j-m]

I was able to take the boat out this morning for about an hour and a half. I started out by warming it up what I thought was good and it was running pretty smooth from my test tank adjustments so I drove it for a few minutes down the lake at the break in procedure recommended 3500 rpms. I then tried my best to adjust the idle mixture screw and idle to achieve the smoothest forward idle speed at 750 rpms I could but it wasn't very easy. Part of it was that it was damp and rainy this morning I just didn't have much patience lol. After getting it close as I could I ended up with the screw set to about 1 1/3 out. I then cruised around the lake at 3500 rpms varying it anywhere from 3000 up to 3700 for the next hour like was recommended. The next stage of the break in says to run 3/4 throttle with occasional WOT bursts so I tried that a few times but at WOT it only achieved 4200 rpms and 34 mph on my phone's gps. Prior to the rebuild I never knew my rpm's, however, I did gps my WOT at 40-42 mph on days it was running good. My load was the same as always the only difference was that prior to working on the motor it had a hydrofoil installed which is not currently on there. Not sure if that made a difference or not. I always read they never really worked. Also of note my filter stayed full, the throttle butterfly was open all the way, and the bulb was hard.

I plan on taking it out again tomorrow and installing the hydrofoil just to see what it does.

I also double checked my prop and it is a 16 pitch 3 blade aluminum one. My boat is a 17ft aluminum bass boat. I think the bottom width at the transom is 48" which is a little skinnier than the modern alum bass boats which is possibly why it squats down in the water more than I feel like it should. So I was thinking I may need to go down in prop pitch...although it would take a mighty big pitch drop to get me from 4200 rpms to say 5000 which is the middle of the recommended WOT range.

 

[scout-j-m]

To add to this, I also hooked up my multimeter to the positive ignition wire and a ground wire up under the dash. At 3000 and above rpms it was showing about 15.5 V. Was that too high? I was thinking the regulator side was supposed to regulate the output to ~14V. I had also read that any problem with the rectifier/regulator can affect the ignition system performance at WOT. Just a thought I wanted to add until someone chimes in.

I'll snap some pics of my boat this afternoon so yall can get get a good idea of what I have.

 

[pnwboat]

I don't think I would purchase a prop just yet. Put some more hours on the motor before you do anything. Make sure the motor is trimmed up to it's optimal position for maximum RPM/speed. Not having the hydrofoil will probably affect the way the motor needs to be trimmed for maximum speed. Do you have hydraulic Tilt/Trim?

Doesn't look like the regulator is doing the best job of regulating the DC voltage. It really shouldn't go above 14.5 VDC, but 15.5 is not a show stopper. Yes if the Rectifier/Regulator has failed, then it can affect the ignition voltage output of the stator. You can temporarily disconnect the Rectifier/Regulator and see if it has any affect on WOT RPM.

 

[scout-j-m]

Thank pnwboat.

I do have power tilt/trim and utilized it to achieve my results from above.

I will get around to taking it back out on the water one day after work this week and will try unhooking the rectifier to see if that makes any noticeable difference. I also will try removing the tinytach knockoff I have wound around one of the plug wires just in case. I also do need to redo my static timing as I believe I set it to 32 deg at cranking speed with the LU disengaged by disconnecting the shift linkage.

I need to still take a couple pics of my boat to post here. Maybe I can get some video on my next trial to post here too.

 

[scout-j-m]

The plan is to take the boat out tomorrow afternoon after work. I am going to play around with disconnecting the rectifier as stated above and verify/set the wot timing dynamically on the water. I'll take off that tinytach too just to eliminate it as a cause (even though not sure how it could hinder it).

But I had one last thought I wanted to throw out there beforehand. The new CDI Electronics switchbox, had two black/yellow wires coming from it. The directions state one is the kill wire and the other is for a rev limiter, if equipped, but doesn't state what to do with the rev limiter wire. I assume tape it off. I currently just have it hanging there though as it is a female connector and has the rubber bullet connector cover insulating it from any ground contact. Anyways, my kill wire from the wiring harness is a male plug but had a small extension of wire with female ends going to the old switchbox's kill wire. I left that extension which means I connected the male lead from the new switchbox to the motor's wiring harness (confused yet? lol). So the gist of all of this...is it possible the rev limiter switchbox wire is connected to the ignition kill wire from the harness and if so would the ignition system even work or on the flip side would it even matter?

 

[pnwboat]

I don't think it matters whether Kill Switch wire and Rev limiter wire from the switch box are reversed. I would bet that if you took an OHM meter and measured between the two ends coming out of the Switch Box, you would probably read a dead short. If you do, then there is no difference. If you don't see a short, then I might consider reversing the wires.

Make sure that the carburetor butterfly is pretty close to the horizontal position when you're at WOT too.

Hope all goes well with your test!