Topic: 1972 Evinrude High Speed Miss – Antique Outboard Motor Club,Inc

This topic has 22 replies, 9 voices, and was last updated 5 years, 1 month ago by dan-in-tn.

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February 8, 2019 at 7:27 pm #166391
bobw
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US Member
While out running my ’72 Evinrude 25hp yesterday, I noticed it had developed a mid to high speed miss. It idles well and is smooth up to about half throttle and then develops what sounds like an ignition miss. I had previously installed new points, condensers, coils, wires and plugs in my restoration project last year. I pulled the flywheel today and checked things out. I found the #2 cylinder points a little wide at about .025 and during that process noticed I had foolishly installed the magneto cam upside down during my restoration work. I’ve made those 2 corrections and ran a quick spark check – I’ve got hot blue spark at 1/4″ gap. I don’t see any sign of spark grounding on the plug wires or mag plate. Could those 2 errors alone have caused the high speed miss or anything else I should double-check before I close the mag up again?

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."
February 8, 2019 at 8:13 pm #166392
frankr
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US Member
I’m very surprised it ran at all with the cam upside down.
February 8, 2019 at 8:14 pm #166393
bobw
Participant
US Member
So was I.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."
February 9, 2019 at 6:43 am #166416
billw
Participant
US Member - 2 Years
Sure sounds like ignition was probably the issue, with all that being wrong! However, if it still doesn’t work, or starts to misfire down the road, be advised that those engines are somewhat prone to failing head gaskets and getting water on the spark plugs, especially if it is, or was, a s salt water motor.

While on the subject, the 22 cubic inch OMCs are so prone to seizing up during storage that I have been fogging mine out every time I finish running one. I can’t even count how many 22 cubers I have seen die of internal corrosion. Such a shame; as they are great motors.

Long live American manufacturing!
February 9, 2019 at 8:03 am #166418
durco
Participant
US Member
If you have not cured your problem then check for armature plate wear/play. If the plate has wear, the motor will not stay in tune at the full range of rpms, as the point gap will continuously change……..
February 9, 2019 at 9:37 am #166426
bobw
Participant
US Member
Thanks guys. This was a salt water motor in its previous life but during the tear-down, I found the block to be in good shape. I replaced all the powerhead gaskets as part of the restoration including the head gasket.

I’ve also been fogging this motor after every use, as I had heard they were prone to internal corrosion.

I’ll be sure to double-check the armature plate for any play, but I suspect the points and cam issue were the problem. Still can’t believe it ran at all with the cam upside down. That at least explains why it was so hard to start!!

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."
February 10, 2019 at 11:43 am #166525
fleetwin
Participant
US Member - 2 Years
Well, I am not convinced this is actually an ignition miss….You mention the engine idles and runs at WOT OK…. So, the miss/rough running is occurring at mid range speeds, correct?
Have you checked the throttle cam pick up adjustment? It will run rich at midrange if the cam pick up is retarded, it will sound like an ignition miss….
Keep in mind these engines are not the smoothest running engines, since the recirculation system was added and overboard drains eliminated….I just don’t want to see you spend hours trying to fix an engine that may not be “broken”.
I too, am surprised the engine ran at all with the cam upside down…
Perhaps those two issues will solve your rough running/missing issues….
February 10, 2019 at 6:57 pm #166589
PugetSoundBoater
Participant
Would this internal corrosion issue effect my 1981 Johnson 25hp J25RCIM? Is that a 22 Cu In motor?

I fogged it after the end of the season 2017. I use it in salt water and barrel flush it after every time i use it with Salt Away.

"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson
- This reply was modified 5 years, 2 months ago by PugetSoundBoater.
February 10, 2019 at 8:55 pm #166597
bobw
Participant
US Member
Fleetwin – I probably didn’t articulate the problem well. The miss was starting at mid-range and continued up to WOT. I did check the throttle cam pickup and it was spot on. I adjusted the points and installed the magneto cam correctly so I think that will take care of the problem. Haven’t had a chance to run it again yet but should get it done later this week.

Still can’t believe I put the cam in wrong – it has TOP noted on it for a reason!! Reminds of the old joke about how some people need to have the bottom of their Coke bottles or can labeled “Open Other End”.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."
February 11, 2019 at 5:40 am #166614
billw
Participant
US Member - 2 Years
Pugetsoundboater, yours is not the 22 cuber in question. I think it is 32, if memory serves me. Anyway, they didn’t seem to be as prone to the problem of locking up in storage; although I did see a few of them blow a head gasket and misfire, due to water on the plugs. If that were the case, it would definitely lock up in storage! The blown head gaskets would sometimes come after an overheat, but not always.

Long live American manufacturing!
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