Reduced RPM/Speed after new stator/flywheel

[grizzadms]

Due to an unfortunate factory defect on my 1998 Johnson 225 Ocean Runner, I had to have a new flywheel, stator, and flywheel bracket put on my motor. After these things were replaced, I noticed I was only getting 5000 RPM and 40 MPH when I previously got 5400 RPM and 43 MPH with a similar load at WOT. Not a big deal but I mentioned it to the repair shop and they happily said to bring it in and they would adjust some things. I am by no means a mechanic but they said the timing was already set to "max timing" so that could not be changed, but there was something else they said they could adjust. However, now the boat only gets 4800/4900 RPM and 37MPH. I know I could take the boat back to the mechanic and they will adjust it again (which I may end up doing). However, it is a pain to take off work, go to the marina, hook up the boat, drive it to the mechanic to drop off, then do the reverse to pick it up. I will call them and see if they will explain to me what I can adjust myself to possibly avoid the hassle of bringing them the boat again but I was wondering if any of you might have any suggestions. If there is something I can adjust myself, any tips will be appreciated.<br /><br />Thanks....grizz

 

[clanton]

Re: Reduced RPM/Speed after new stator/flywheel

I would do the timing as outlined in manual,check timing indicator with piston locateing tool to insure timing indicator is at top dead center, then check timing at 5000 rpms loaded engine. Throttle control should be at max throttle. Then mark flywheel and check all 6 cylinders. There is also a chance the new stator is wimping out. What was wrong with old flywheel and stator, bolts come out of upper bearing housing?

 

[grizzadms]

Re: Reduced RPM/Speed after new stator/flywheel

Clanton, How did you guess? That is exactly what happened.<br /><br />Not sure I have the proper tools or know-how to try what you suggest but I will bring it up to the mechanic. They supposedly adjusted the motor to "max timing" already and have been adjusting something else.<br /><br />Thanks for the suggestion.<br /><br />grizz

 

[captrich]

Re: Reduced RPM/Speed after new stator/flywheel

I had a similar problem on my Yamaha a couple of years ago and it was finally found to be a faulty high speed relay not letting max RPM's develop.The engine maxed out at 4400 vs 5400. <br /><br />Ps; it took most of the summer to find the problem. Good Luck!

 

[grizzadms]

Re: Reduced RPM/Speed after new stator/flywheel

Capt Rich,<br /><br />How did you did you diagnose that relay problem?<br /><br />grizz