20hp MErc PROBLEM(S)>>>???

[DPSchmidt]

This motor had not spark to start off with the owner told us the flywheel dropped the magnet out of it. So it ruined the pick-up coil. replaced it and starts up fine but runs very high.... Throttle is closed. If I spray down around the base of the motor it slows down. <br />Could the base gasket have a leak ask be sucking air? Does this gasket also keep water out of the top end>? <br /><br />Back to the flywheel... We put the magnet back in. It is a 1 piece magnet. how would you know where to put it back in? Does mercury sell a magnet kit? Whne we turn thew motor over it seems it is out of time but does run. I believe the magnet could be moved be 1/2" or so and we could be knocking ourselves in the head trying to figure this out.>?<br /><br />Thanks in advance<br /><br />Mercuy 20hp Ser# 5409543

 

[DPSchmidt]

Re: 20hp MErc PROBLEM(S)>>>???

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[DPSchmidt]

Re: 20hp MErc PROBLEM(S)>>>???

OK>... One more question....<br /><br />How do you replace the upper and lower seals?<br /><br />Do you have to split the cases?<br /><br />ok 2 questions...<br /><br />How do you get the spline off of the crank?<br /><br />Thanks...<br />

 

[NathanY]

Re: 20hp MErc PROBLEM(S)>>>???

First off if you dont have a manual you will need to get one before attempting any complex repairs.<br /><br />Now, what are you refering to as the spline?<br /><br />Yes you will have to split the case to replace the seals. If you are going to go that far and you have the money, you might as well replace the rings, and have a peek see at all the bearings.

 

[DPSchmidt]

Re: 20hp MErc PROBLEM(S)>>>???

The female splines are on the end of the crank..<br />To slip onto the drive shaft... <br /><br />How does it come off...<br /><br />I do have a clymer manual and it is not all that great... <br /><br />I am guessing that I have a lower crank seal leaking...<br /><br />Thanks

 

[dkondelik]

Re: 20hp MErc PROBLEM(S)>>>???

Mornin' DPSchmidt,<br /><br />Re. "one more question"<br />With the shift-shaft linkage disconnected, can you lower/drop the "leg" enough to view/access the crank-shaft/drive-shaft junction?<br /><br />let us know what you see. perhaps the selective application of lubrication (WD or penitrating oil), focused heat (from heat gun or prop torch) and judicious application of impulses (wack it with a hammer), can help free the connection.<br /><br />You'll want to replace that lower seal. The crank case must be "tight". if your not air tight, engine operation will surely suffer as it wont draw frm the carbs correctly, nor will it compress air/fuel mix into the cylinder at the designed rate. Will likely lead to catastrofic failure (over heat/melt-down piston/cylinder).<br /><br />Good Luck<br />HAVE FUN!

 

[alcan]

Re: 20hp MErc PROBLEM(S)>>>???

That spline/socket is the crank. It does not come off.