Stator check

[kmdfluker]

how does one check the stator to ensure its working. I have a miss under load after reaching 3800 RPMs, but depending on load can be even high RPMs

Changed everything, but stator.

 

[HighTrim]

Re: Stator check

Will need to know the motor you are referring to, model number? Maybe a little more background on what was serviced and why?

 

[HighTrim]

Re: Stator check

http://forums.iboats.com/showthread.php?p=1557055#post1557055

Ok went back to your previous posts, a 96 150 correct.

I am by no means an expert, but do not feel that your problem is the stator, although check it none the less. Is this the 150 commercial 60 degree eagle motor? I saw you are running the QL78YC plugs in her.

Have you rebuilt the carbs yet? Checked for fuel restrictions, anti syphon valve, etc...?

Get a vacuum gauge and hook it inline on the fuel hose before the engine, along with a clear section of hose. Take it for a spin, noting the readings and monitor the fuel flow through the clear hose.

Findings:

-Vacuum of less than 2 inches and air bubbles in the clear hose indicates an airleak into the fuel system
-No air bubbles and less than 2 inches indicates a bad fuel pump
-Vacuum over 4 inches indicates a restriction.

Sample gauge

"http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMEBTOX%3AIT&viewitem=&item=4610113711&_trksid=p3984.cTODAY.m238.lVI"

 

[HighTrim]

Re: Stator check

Another thought after thinking about it.

Could your problem be overheating caused by improper timing. At higher rpms the engine gets too hot because of pre-detonating and automatically shuts down by the thermistor in the engine block which prevents the motor from desroying itself when she overheats. Another issue may be water circulation being insufficient at higher rpms. Check your timing, referring to Joe Reeves instructions in the FAQ.

 

[kmdfluker]

Re: Stator check

High Trim

My engine model is a 150EXEUE.

I don?t see my last reply so I?ll restate:

The only carb cleaning I?ve done is with OMC spray. I do that at least once a year.
At the end of 2006 I used the spray and when it was time to take out the boat, which I didn?t run much after the carb cleaning, the engine started fine then stalled for a very long time while I drifted about. Finally started and that was it until 2007. My missing started first time out in 2007 and didn?t stop the entire year.

The miss is rhythmic like run miss run miss. Happens under load usually over 3800 RPMs. When I pull back under 3800 it immediately goes away. In fact it only happened once under 3800 RPMs when I had a full boat against the wind. If I push the engine it goes no bogging down. Note that if I really push it 4200-4400 RPMs and it happens I get a big bang in what appears to be the lower unit or it could be anything. Bottom line is you get the sense that the engine pauses then goes again. At the high RPMs I naturally pull back right away and it stops once I go slower.

I was also wondering about the overheating. In 2006 I did not change my water pump. I had fair pressure reading, but in late summer the engine would overheat on long trips do to water temp in bay, weed build up, and not enough pressure. I did change the water pump before 2007 and have very strong pressure again. NO more overheats. I did overheat a bunch of time in 2006 and engine warning would sound and I?d shut it down before it went into auto shut down and run at idle until it cooled down. What confuses me is my problem started right away in April. Water temps are very cold in NY in april and I was running less than 5 min when the first miss happened.

To me it just seems to be load related, Some days (not many) it would run fine up to 4000 RPMs. I even had days when it ran at 4500 RPMs. These days were calm no wind and by myself ? no load.

Also ? at the end of this year the engine would start I?d just idel at the dock 3 ? 5- 10 Min. Then it would stall and be very hard to start. Could my problem be related to the kill switch.

Full pump ? I had thought that and may have gotten bad advise that said when it goes it goes and you won?t run at all.

My biggest problem is the mechanic said it could be thousands of dollars to figure it out and recommended I run it until it really breaks then fix it. Of course I?d rather try to fix it.

Thanks any more thoughts.

 

[kmdfluker]

Re: Stator check

High Trim

I don't kniow where to review this:

Joe Reeves instructions in the FAQ

 

[CharlieB]

Re: Stator check

I've run into a similar problem twice,

re-adjust the shift cable so as to put just a little more pressure into FORWARD gear and re-test.

What may be happening is that when you get FULL LOAD the shift dog fails to hold and 'bounces' out of gear.

This progressively gets worse until you end up replacing the shift slider and forward gear.

Hopefully the cable adjustment will get you by another couple of years.

 

[kmdfluker]

Re: Stator check

Charlie B

Thanks for the input,

I made that adjustment already and no change.

The thing that bothers me is the loud banging noise it makes when it happens at high speed, which makes me lean to the lower unit. I wonder if I?m past the point of no return on the clutch. How would I know that?

Will it get progressively worse and then just not stay in gear?

I wonder if the noise at high speed is a backfire. The first time it happened WOW what a bang - sounded like I hit something in the water.

At the lower RPM?s it is like a prop slip -

All I can say is this is pain staking. So many possibilities and local pros telling me to wait until it brakes (doesn?t run) then fix it.

Or should I just get a new one???

 

[HighTrim]

Re: Stator check

Well a miss and a loud bang, like hitting a log, are 2 totally seperate things. The way you descrbe it now it does sound like a clutch dog. The lobes of the dog are precisely machined edges, and when these edges start to wear or round, and you increase the rpms, the pressure of the gear against the dog forces them apart, causing it to jump out of gear, then the shift cables tension forces it back in, giving you the sensation that you hit something.

This is usually caused by improper shifting by the operator. When shifting, ensure that you make deliberate quick shifts. Slowly shifting into gear causes the edges of the dog and gear to bang against one another, wearing them down.

Testing the prop to be spun is quite easy. Simply draw a line across the hub and prop, or use the cotter pin as a center line, run the motor until you hear it "slip", then check if the lines are askew. If they are no longer lined up, the prop will need to be re hubbed, much cheaper than buying new. Or if the prop is in poor shape, may want to invest in a new one.



You may very well have more than 1 demon that you are trying to chase.

 

[kmdfluker]

Re: Stator check

OK

I've checked the prop a number of times and thats not it, because that's what it felt like from the begining. It just seems like the engine is pausing and I went in the electrical way first.

So this miss under load could be the shift/clutch dog. OK I've only had the bang 2 times because I don't push it past 4000 RPMs much. I just run up to 4000 if it misses I pull back if it doesn't I stay there. Only during a few test I ran it past 4000 and 2 of the times I got the bang.

Why don't I get this bang at lower speeds?

I use the boat with a lot of starting and stopping - fishing in channels and creeks so I can see how this might put wear on the DOG.

I did adjust the shift cable once this past year on the recommendation, but I had no change. Maybe I went in the wrong direction. How do I make sure?

If the DOG is the problem how can I make sure? Is it an expensive repair?
or do it yourselfer?

Thanks for all your help!!!

 

[HighTrim]

Re: Stator check

You will need to drop the lower. Inspect the dog and gears for wear and rounding. It is definately a job you will want a manual to do. You will also need a few specialty tools, such as a big pair of snap ring pliers.

It only does it a high rpm because that is when more pressure is applied to the dog and gear, causing them to jump apart if the machined edges are worn.

 

[kmdfluker]

Re: Stator check

High Trim

Ok - so at the lower speeds whats happening? Just slipping in and out like a prop slip or miss vs the bangggg at high speed???


I think I'm moving away from electrical to the DOG. I guess I can take the lower unit off and have it checked out somewhere.

Another tid bit is this engines lower unit, since day one, has had some H2O in the lower gear oil. Maybe thats also contributing to the problem. I have had some seals changed on the shifter, but only held up for a year both times.

Thanks for your help !!!!!!!

 

[HighTrim]

Re: Stator check

If that is the case, you may want to look into getting a used or rebuilt lower unit then. Check ebay.