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can't get points gap right

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Billhein94

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I am tuning up a 75 25HP (25502B) and I just replaced the points and condensers, but I can't seem to get the points adjusted to .020. They will not open that far with the adjustment screw. I had to push them open with my finger to get like a .019 gap and that was as far open as I could get them then I torqued down the screw to keep them in place. I move the plate around a couple of times and it appears to be holding. Out of curiosity, I put the flywheel back on and had good spark nice and blue jumping almost half and inch. Did I do something wrong or should I just roll with it?
 
The part number of the points must be 580148... is it?

The flywheel key on the crankshaft must be lined up with fiber portion of the point when setting... is it?

Set the points so that a .020 gauge will slide thru but a .022 will not.

The points should be able to be set easily... if yours won't open beyond .020... you're doing something wrong, you've got the wrong points, something!
 
Are the points OEM? I had some recently (posted in another thread) with the same issue. Could only get 0.008" gap. I was in a hurry, so I bought some Sierra points off of Amazon and they set perfectly. I checked the PN and the OEM were the right number, just not the right dimensions. When I posted, others had seen similar.
 
joereeves said:
The part number of the points must be 580148... is it?

I points were part of a kit that I got from this website

The flywheel key on the crankshaft must be lined up with fiber portion of the point when setting... is it?

The points are lined up with the "set" position on the crank. . .plus that is were the points are open to there fullest potential.

Set the points so that a .020 gauge will slide thru but a .022 will not.

I can't get them bigger than .016 unless I force them open.

The points should be able to be set easily... if yours won't open beyond .020... you're doing something wrong, you've got the wrong points, something!
Click to expand...

I've watched plenty of videos and am following the service manual. I thought this should be pretty easy.
 
What happens if you back the cam screw out one full turn.----And you tighten the hold down screw BEFORE using the cam screw to set the gap.-----That hold down screw does have that special washer after all.
 
Well----I have only been working on motors since about 1968.----It is a special , thin plain washer.-----Used on that magneto from about 1950 to 1986 or so.
 
Well----I have only been working on motors since about 1968.----It is a special , thin plain washer.-----Used on that magneto from about 1950 to 1990 or so.---Part # is 510208.
 
I wasn't questioning you about the washer, I was just letting you know that I don't think one was there when I took off the old points. Maybe whoever put these on originally didn't know that they were necessary. .is that what is causing my troubles??
 
There have been numerous recent reports of defective 580148 OMC points that won't adjust properly. Return 'em.

Yep, since 1950. No problems till recently and a new mfr.
 
So, I didn't get a chance to check on the points, but my compression tester came in the mail so I decided to check that out instead. I got around 75 on one and about 80 on the other. That was quite a bit lower then I was expecting. I walked away from the motor, trying to decide what my next step is and how far down the rabbit hole I want to go. Is it worth pulling off any covers and replacing gaskets? Could the reed valves have any effect on this, or should I just commit to a complete tear down? I also have a 18 HP that is in pieces right now. . I might check compression on that one and maybe shift my focus.
I had the 25 HP running OK last year there were just a couple things I want to fix. The more I dig, the more I want to fix. It has potential, just not sure how much effort I want to put into it.
 
Reed valves have nothing to do with compression in the cylinders when testing.----Remove bypass covers to have a look at pistons / rings.
 
Correct.----Just a simple gasket to make if they tear apart.----Hardly any money involved with a great amount of information gained.
 
I am not a mechanic, but am willing to learn. I appreciate all the help. I am liking it so far. I just lack the experience to do anything complicated, but am willing to try
 
Part of the oil recirculation system.-----Worked on my 20 HP 1975 model ( Canadian marketed ) yesterday and made sure hose / nipples were clean.-----Not a vacuum hose !
 
racerone said:
Those points and that washer were used from 1950 t0 1990 !!
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What are you all mad about? You said the magneto was used from 1950 to the 90s. I simply pointed out that Magneto was only used from 73 on. Since I am sure you know that a 1975 25 hp uses the low tension magneto not the Universal Magneto.
 
Billhein94 said:
but my compression tester came in the mail so I decided to check that out instead. I got around 75 on one and about 80 on the other. That was quite a bit lower then I was expecting it.
Click to expand...
Try your tester on the lawnmower, chainsaw, other motor, one you know runs. It might be a crap Mail or fed tester.
The first one I ordered through Amazon gave readings of 70ish, on an 8hp that runs well. Sent it back & got one from an auto parts store. It read 115 on the same engine.
 
flyingscott said:
What are you all mad about? You said the magneto was used from 1950 to the 90s. I simply pointed out that Magneto was only used from 73 on. Since I am sure you know that a 1975 25 hp uses the low tension magneto not the Universal Magneto.
Click to expand...

Nobody mad here. Check it out, the parts book here at marineengine says the 1975 25 hp with Lo-Tension mag continued to use the old 580148 points set

http://www.marineengine.com/parts/j...=25502B&manufacturer=Evinrude&section=Magneto
 
Last edited:
Forget it !!-----The basic magneto was used from 1950 to 1990.----The last models ( 22 cubic inch ) of these in 20 / 25 HP just moved the coils away from under the flywheel.-----They used a driver coil under the flywheel.----And there was room for an A/C lighting coil or battery charging coil.-----Other than that the mechanical pieces of the lo-tension and high tension magneto were the same.
 
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