1973 Evinrude 9.5 Slow spd. adjustment

Rick.

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Hello All. Well i fired up my motor tonight. I have it running very well at slow speed. The manual says to back the adjustment screw out 3/4 turn and fine tune from there. My motor sneezed real bad at this setting and by the time I had it running well the screw was backed out about 1 1/2 turns. It shifts well into either gear and doesn't bog down. On previous engines I've always found that I've had to lean the adjustment but in this case I had to make it a lot richer. Is this OK or is it a sign that I didn't get the passage clean enough when I cleaned the carb.? I must also say that there was quite a bit of accumulated exhaust oil ( more than other motors I've run) in the barrel and it seemed to go through much more gas than my 9.9 would have in the same amount of running time. Thanks for any help or comments. Rick.
 

freddyray21

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

sounds like something clogged in there. when you cleaned the carb did you pull the welch plug and clean the small holes out under it? Might be the culprit if you didn't.
 

Rick.

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

No I didn't. I'm scared to as I'm really skeptical about getting the new one to reseal. It says to tap them with a punch but I just don't think it will seal right. I think I cleaned it real good though. I was careful to get every orifice I could and from both directions. Rick.
 

freddyray21

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

they actually seal very well. to get one out I use a real small straight screwdriver and just tap it lightly to go through the plug then pop it out. you will see three small holes. A single strand of wire will usually unclog them. They are pretty small, but essential for idle. I tap the new plug in using a drill bit just smaller than the plug. Use the end that does in the chuck against the plug get it centered and tap it in. I then for just the sake of it spread some seals all on the plug. Don't know if I ever had one leak.
 

tashasdaddy

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

adtually you are fine, 1 1/2 turn is the usual starting postion. for some reason in the 70's they did say 3/4 but we ended up turning them out.

Default Carb Needle Adjustments For Asorted Carb Variations by Joe Reeves
(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
 

F_R

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

The book isn't always right. If it runs well at 1 1/2 turns, leave it at that and don't be worrying about it. If the holes under the plug are clogged, it won't idle no matter what you set the needle at. In fact, I was doubtful that the book even says 3/4, but I looked it up and sure enough it does. That just doesn't sound right though.
 

tashasdaddy

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

my 71 50 ran great at 3/4 out, my little motors liked more fuel.
 

Rick.

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

Being doubted by a "Fleet Admiral" is just fine with me. This motor ran for the first time in many many years last night and I must say I'm very pleased. As far as the mounts go they are almost rock solid and I didn't get any exhaust leakage into the cowl either. When it was "sneezing" it scared me spitless but now I know what sneezing looks and sounds like. Thanks to all for your help. Rick.
 

tashasdaddy

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

now change the impeller if you haven't. no point in burning it up.
 

Rick.

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Re: 1973 Evinrude 9.5 Slow spd. adjustment

TD. You never cease to amaze me. How do you know these things? I've replaced points, coils , condensers, fuel lines, plugs, gear lube, etc. but the one thing I didn't replace........ actually it was back ordered and should be in soon. Question: If my 9.9 tell tale is called a Pee Hole, is the tell tale on the 9.5 called an A_ _ Hole. It is much bigger and shoots the water well beyond the barrel rim. Thanks, Rick.
 

nightstalker

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Dec 10, 2003
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Re: 1973 Evinrude 9.5 Slow spd. adjustment

We used a 72 or 73 9.5 Rude on our duck rig for years and it burned quite a bit more fuel than any of our slightly newer 9.9's. I think it's just the nature of the beast. By the way, that 9.5 was a great engine, I wish we still had it. Maybe someday we will, if we ever find the SOB who stole it.
Nightstalker
 
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