No speed, Technical ?

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• Apr 27, 2004

• #1

Okay I can not find a flywheel for my engine. Its a 1982, 40 Hp merc. Although the 3 magnets left were chipped and one broken in half, I evened them up and glued them in my flywheel, on both sides. Engine ran great at home, so I took it to the river. Engine continued to run great in the river but I only got it up to 10MPH at WOT. I messed with the timing some but still no speed. I put the timing light on both plug wires and both had spark. So what could be the problem here? If I am missing some magnet would the engine run alot slower?, does anybody know how many magnets belong in this flywheel?. Should I look at some other part?. Thanks for any help, Bryan

 

Z

ZmOz

Captain

Joined

Aug 13, 2003

Messages

3,949

• Apr 27, 2004

• #2

Re: No speed, Technical ?

The magnets shouldn't have anything to do with it. What size boat is this on, and what is your normal WOT speed? Are your RPMs where they are supposed to be?

 

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• Apr 27, 2004

• #3

Re: No speed, Technical ?

the boat is a older 16 foot tracker deep V. I have had the boat up to 27 MPH at 5200 RPMs. Today Running in the water the RPMs are around 5000 WOT, I kicked them up to 6000 for a second and got the speed up to 13 MPH

 

K

kd6nem

Chief Petty Officer

Joined

Jul 25, 2003

Messages

576

• Apr 27, 2004

• #4

Re: No speed, Technical ?

Spun prop hub?<br />Does the motor SOUND like you really have that many RPM's? (Could the tach be fooling you?) Same prop?<br /><br />OR: Forget to untie from the dock, bring in the anchor, or take the boat off the trailer? <br /><br />Same RPM's should accomplish about the same speed unless the power is not getting to the water somehow.

 

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• Apr 27, 2004

• #5

Re: No speed, Technical ?

I would have to say no to the spun prop hub. Reason bieng I was running this boat last week at about 25 MPH, but was running very inconsistant, missing and eventually would run off one Cyl. When I pulled the flywheel to check on things, I noticed the Magnets were detached from the flywheel and broken up. It does sound like the RPMs are correct as far as I know.

 

K

kd6nem

Chief Petty Officer

Joined

Jul 25, 2003

Messages

576

• Apr 27, 2004

• #6

Re: No speed, Technical ?

Hmm, I have no idea then. If the motor is turning full rpm's, the prop is the same, power is actually delivered to the prop, only other thing I could imagine were the things I mentioned tongue in cheek- like towing the dock or trailer (ie: some external drag). Something about this picture I'm not seeing.<br />If the rpm's are really up there then they must not be getting to the prop somehow.<br /><br />Did those magnets do any other damage when they came out?

 

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• Apr 27, 2004

• #7

Re: No speed, Technical ?

As far as I can see the Magnets did not break ant other part. I do not know how many magnets should be in the flywheel. One guy told me if I do not have enough magnet, I will have a shorter weaker spark. I have been looking at some photos of flywheels and noticed the magnets go all around, and all have is 2 that seemed whole but were chipped and one that was cracked in half.

 

K

kd6nem

Chief Petty Officer

Joined

Jul 25, 2003

Messages

576

• May 4, 2004

• #8

Re: No speed, Technical ?

Hey WLD, ever get it figured out?

 

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• May 4, 2004

• #9

Re: No speed, Technical ?

No not yet. I did finally find a flywheel, I hope it is the correct one. The flywheel I am waiting on has magnets all around, where mine has about 2 1/2.

 

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• May 6, 2004

• #10

Re: No speed, Technical ?

Got my flywheel in today, Unfortunatly for me wrong one, so back to the search.

 

W

Wildlifedesigner

Seaman Apprentice

Joined

Sep 3, 2003

Messages

47

• Jun 7, 2004

• #11

Re: No speed, Technical ?

Well I finally got me another flywheel that matched Thanks to Norhern outboard.<br /> Took it to the lake yesterday and moter ran pretty good, at 5000 Rpms I got it up to 25 MPH, I am sure I could get more speed once I can get it to plane correctly.<br /> So I would say that the cracked magnets actually lost thier Magnetism? What do you think. This flywheel also only has two magnets, they do not go all the way around the inside.