Evinrude 9.9 - Quiet Runner?


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Well-known member
Feb 24, 2023
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Cedar Lake, IN
Had this 9.9 kicking around for a year or so. Decided time to get it going. I had it running when first got it, but was leaking fuel. Changed all the lines, put a new pump and filter on it. First pull, nothing, 2nd pull and I swear.....it was running. So quiet though it was barely audible. Then it died. Another pull, same thing. I swear it was running! for all of 5 seconds, but so quiet. Now I got nothing. Yeah I know you probably all think I'm nuts.

Pulled the plugs. Clean, pretty much dry. Got spark. Should have compression, I checked it before. No start. These are the times that try my patience. Didn't figure it would run well without cleaning the carb and cleaning up the points, but weird it's now dead. I even sprayed fuel right into the plug holes.

Anybody ever have a motor act this way?
Well a couple hundred rock n rolls shows sure didn't do my ears any favors, but I can normally hear a motor running loud and clear! This is just Twilight Zone stuff here. After further thought, could the exhaust be blocked? I *think* the exhaust may come out around the prop, but don't really know. This is my first 9.9. It's a 1975 M/N: 10524C

Could this motor actually be super quiet? I had it running last summer and did not notice it being particularly quiet. With gas spewing out the side of the pump though it was a very shot test.
Is is CDI or points ignition? I always felt like I could get a small a small 2 cylinder points motor to run well at ridiculously low rpms.
It's there Pappy. 1975. Pretty sure it has points. I know they need attention along with the carb. She's throwing a decent spark though, 5/16"
Okay thanks.
1974-1976 9.9-15hp engines had a myriad of issues that resulted in several service bulletins. Most of which were aimed at the ignition side of things. On your particular system there was an ignition stabilization kit that has long since been discontinued and NLA that stabilized the mag plate and kept it from moving laterally. This is a probable cause of what you are seeing in fact I believe we just dealt with one of these in here not too long ago. When the mag plate moves laterally (side to side) the points gap changes radically to the point you may lose ignition. This MAY be the cause of what you are seeing and from your description it makes sense. You can retro fit later CD ignition onto this engine by sourcing a used engine or however you want. That is one avenue. This is not to rule out any other source of issues that can create this scenario. Basics first in this forum before we jump down any one particular rabbit hole but this particular one can cost a lot in new parts chasing it down only to find the proper parts are NLA.
Thanks a ton for all that info Pappy. Can this lateral movement be checked? Maybe by just trying to push it side to side? I don't have any money in this motor really, I got if from my Cousin Tom right before he passed away. It also has a busted upper thrust mount that is NLA as well. Sounds like this one may be a lost cause.

So am I nuts to think this motor was running, but super quiet? This is what puzzles me and if I never saw it, wouldn't believe it possible.
How much lateral mag plate movement is too much? Or should there not be any?

How much lateral mag plate movement is too much? Or should there not be any?
There should be virtually no lateral movement. That issue coupled with the broken upper mount would put that engine into a spare parts engine to me. They were not OMC's best effort compared to 1977 and later 9.9-15hp engines.
That's pretty much what I've been thinking. Been looking for another 9.9 or 15 to cobble to together to make one good one, but haven't had any luck so far. Can I check for that lateral movement without pulling the flywheel?
I can sell you a set of NOS Atom red ignition modules. this completely negates the issues with a sloppy plate as it take out the points and condenser (well you can clean the points and leave them in, just be sure to set the gap so wide they dont close). it uses a transistor, and completely transforms these into much smoother, easier starting motors IMHO. Ive done a ton of these conversions as i'm obsessed. interestingly, the green ones that are supposedly for briggs & stratton appear to be identical in output and timing, which makes sense since briggs basically have the same ignitions. the green ones are easier to find. this setup is superior to the CDI ignitions as well, i've never heard of an ATOM or sierra magnatune failing.
Easier with the flywheel off but knock yourself out..........................
Not following what you're saying. Seems like I'd be "knocking myself out" to pull the flywheel for no reason. it's not a big deal to pull it, just thought maybe it's a waste of time.
Not following what you're saying. Seems like I'd be "knocking myself out" to pull the flywheel for no reason. it's not a big deal to pull it, just thought maybe it's a waste of time.
Its just a matter of a $35 ebay universtal small engine puller, 3x 1/4-20 screws and off she comes. when they where newer you could just bear-hug it while rapping the loose flywheel nut with a hammer, but always hated doing that. you'd disconnect the point wire and attach it to the module. other end goes to a clean powerhead ground. thats it. you can splice in the stop switch if you like because these idle so low with the modules sometimes it won't stall, and choking it is annoying for harder starting after.
I have a flywheel puller. Just kinda like to avoid doing things the hard way. Like by taking off parts for no reason. When I get a chance I'm going to pull it anyway to dress and set the points. None of this seems likely to be the issue though.

Recap: When I got it it started up easily and ran OK, but was spewing gas out of the fuel pump. One year later I put new lines and a pump on it. Started right up again (I think) but is running almost silently. Did it twice and now won't start at all. Seems weird crap always happens to me. Nobody else.
spewing fuel out the pump, or out the gasket the pump sits on? either way it needs a replcement. if the boss mounting screws are loose, it will suck air and stall.
The pump housing was cracked, so I replaced it along with the gasket. I just don't get what the heck is going on with this damned motor. I swear it was running, but it was like listening to it run from a block away. I could barely hear it, but it was doing something.

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