Stator rotated. Will this effect timing?

[dpal]

I have a 93 40 hp Mercury outboard 4 cyl. I am trying to sinc,link, and set timing according to book. Not working quite well. I noticed the stator is rotated CCW about 60 degrees from what the merc manual shows.
(see pictures). Will this cause a false timing signal as I use a timing light on the fly wheel mark?

I realize the trigger is the main timing advance part. I am wondering if the charge capacitors in the ignition unit may not charge or discharge at the right time causing a delay or something in the #1 coil. This might cause a timing light to be misread?

The second picture is my current stator position.

Thank You for your time.

 

[dpal]

Re: Stator rotated. Will this effect timing?

Mounting Rotation of the stator did not change the timing.

 

[j_martin]

Re: Stator rotated. Will this effect timing?

ditto. What's not working well?

edit ding ding ding..... light went off.

When the stator was changed, did a long screw get put in that interferes with the trigger motion?

Ask me how I would know about this.

John

 

[turbinedoctor]

Re: Stator rotated. Will this effect timing?

We need more details as to what led up to replacing the stator and doing the link and sync. Is this a fresh rebuild, just a new stator or what. What exactly are you seeing when you are doing what?

 

[CharlieB]

Re: Stator rotated. Will this effect timing?

ditto.

Ask me how I would know about this.

John

LOL

A LOT of us can make this same statement. LOL

But I'll admit, most of the time I tell them 'Don't ask!' It covers a LOT of personal embarrassment. Some could be candidates for the other board, 'Stupid Human Tricks.......'

 

[dpal]

Re: Stator rotated. Will this effect timing?

The following was from a post about 1 year ago. The link and sinc will not set to factory specs (timing) with out causing the idle RPMS to be to high. Rebuilt carbs, fuel pump, Plugs, good fuel, primer solinoid, and swift kick on the tire did not help. According to the book pictures the stator was rotated a number of degrees and the wiring harness run incorrectly (but worked). I think mercury had a recall and it was replaced under warrenty in 1994.


I have been running this engine with the timing described below because I cannot find a solution. It runs and cranks fine until you run it hard down river before shutting down to get the trailer. Crank it up to load on the trailer and it will not stay running until I full throtle around for a second like blowing it out.

http://forums.iboats.com/showthread.php?t=307952

I have a 1993 Mercury outboard 40 hp ELPTO 4 cyl 2 cycle. This motor is new to me and was running good the 2 times I have had it out on the water except for some sputtering at around 10 mph. I ordered a factory manual so I could check all adjustments. I first noticed the carb linkage wasn?t allowing full throttle while on the trailer. I did not look while running on the water but the RPM on the water is reaching about 5300 at about 29 mph (gps). That seamed average to me for a Pro 17 bass tracker. The motor was idling in the water about right below 800 RPM ? but will not start without choke for a second hot or cold. Now, here?s my problem. Compression equal at 125 psi. I checked the timing using the starter method and it was set to about 6 ATDC, the book said 2 BTDC - 2 ATDC. At full throttle 32 BTDC using the starter method with spark plugs removed. When I set up the timing per the book, I get a high idle situation of 1000-1100 out of the water on water muffs. The carb butterfly valves are closed with no linkage touching. The book says 600-700 RPM in gear in the water. My question is can anyone tell me from experience the difference in idle RPM out of the water and then in the water. I am wondering if the prior owner or tech set the timing lower to achieve a lower idle. It is about 1 hour to the nearest lake to test and I would rather try to get it right at home. Sorry for the long post but I know how important setup info can be.

 

[dpal]

Re: Stator rotated. Will this effect timing?

Next post from last year

Update:
The RPMs on the water is about the same. Makes for noisy shifting into forward. I have rebuilt the carbs, indexed TDC for #1, changed spark plugs, rebuilt fuel pump, adjusted idle screws and checked choke enricher for leaks. The only way I can reduce the idle rpm is to back off the throttle arm screw which places the timing at about 6-8 degrees ATDC at idle.

I did notice I have a lot of play in the trigger under the flywheel. I can move it up and down and in and out about 1/8" or more. It has no play CW or CCW.

Any suggestions are welcome.
Thanks

 

[CharlieB]

Re: Stator rotated. Will this effect timing?

So, if I understand correctly, you are asking what is the CORRECT idle timing?

The book is using the range 2 BTDC to 2 ATDC as a STARTING point to get the motor running.

Idle speed is set by retarding idle timing once the motor is running and the carb idle mixture is perfected.

Idle speed once on the water will be anywhere from 100 to 150 RPM less than on the hosebecause of the additional back-pressure of the water column in the exhaust passage, for this reason idle mixture must also be perfected once on the water, then final idle speed may again be adjust with final idle timing.

 

[sschefer]

Re: Stator rotated. Will this effect timing?

Regarding stator positioning. The stator can be mounted at any position that causes a flywheel magnet to pass over it at the correct time. It does not affect timing but it does affect spark strength if it is off by 1 screw hole in either direction.

Check the output of the switch box at the + terminal of any coil. If your DVA equipped multimeter shows 200+ volts, your stator is aligned correctly. If it shows less than that by a significant amount then rotate the stator one screw hole in either direction and it should cure the problem.

 

[dpal]

Re: Stator rotated. Will this effect timing?

What will the long screw cause the trigger to do and how will it effect the timing?

I do not remember if there was different length screws. If it will cause the timing to cause the high idle RPMs only, I will pull the flywheel again. I did not see anything wrong or binding with the trigger at the time.

Again, the only way for me to lower the idle RPMs below 1100 is to set the timing until the RPM is about 800 in the water. Thats 4-6 degrees ATC difference from specifications.

 

[sschefer]

Re: Stator rotated. Will this effect timing?

What will the long screw cause the trigger to do and how will it effect the timing?

I do not remember if there was different length screws. If it will cause the timing to cause the high idle RPMs only, I will pull the flywheel again. I did not see anything wrong or binding with the trigger at the time.

Again, the only way for me to lower the idle RPMs below 1100 is to set the timing until the RPM is about 800 in the water. Thats 4-6 degrees ATC difference from specifications.

Initial timing is only a reference point so the engine will start. The motors do not have an idle adjustment like you might find on a car, you use the initial timing to set idle speed.

Basically, if the engine likes 4-6 degrees ATDC (retarded and normal) to run at 800 RPM that's fine. Once my engines are running on all cylinders I set the idle to 800 on the hose and then only concern myself with WOT timing from that point on.

 

[dpal]

Re: Stator rotated. Will this effect timing?

Thanks for the info guys, I will do some more checking.

 

[j_martin]

Re: Stator rotated. Will this effect timing?

The trigger rotates with the throttle linkage. That linkage usually has some springs in it. If a screw for the stator protrudes through the mount and interferes with the travel of the trigger, it can prevent it from moving as it should, either failing to full advance, or failing to come back to the retarded position for idle.

Things to check.
Binding in the trigger. The above said screw can do it. The harness from a trigger has to be tied down, usually in one spot quite a ways away from where it comes out of the stator mount. It must be free to move the full range.

Binding in the throttle linkage, preventing one or more carbs from returning to full closed.

Air leaks. This would be found by running it hard, (you said after that is when the symptoms manifest), then at idle spray a fine mist of water around the carb bases or any other possible intake or crankcase leaks.

hope it helps
John