Need help diagnosing Evinrude 9.5 problem

[crosbyman]

try a good decarb… can’t hurt to clean the innards

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[titantn]

quote rjoynt:

The high speed needle is a non-adjustable jet. It is located just inside of the front of the carb down towards the bottom. There is a bolt head in front of it. You can drain the carb by removing this screw before winter or when you are done with it for awhile. When you cleaned the carb, did you take off this part of the carb?

Yes I did pull the carb apart there. I pulled that bolt out too, but didn’t know there was a jet in there. I thought it was just a drain.

[jeff-register]

Many carbs have "Fixed jets" for the high speed part of the carb. Look in a service manual for the correct number on the jet to match your altitude of where you live. There is a tiny number stamped on the jet hopefully, I know Mercury has I.D. numbers. You may have the wrong jet size.

[fleetwin]

Yeah, these engines don’t have a lot of power/top RPM….They start easy, idle nice, and are smooth, but aren’t going to win any races….
Try to take a video of the engine running on the boat if you can…

[seakaye12]

Yes; it’s a 9.5 ….and yeah they aren’t real power-houses…..but they should run really nice none the less…..sure sounds like the OP’s engine still has issues.

I know the ignition system has been worked on and worked on again…..but is there ""ANY** chance that it’s currently running on one cylinder? All it takes is a bit of grease on one of the points 🙂

[garry-in-michigan]

We had a 9.5 horse Evinrude Sportwin show up at one of our meets that started and idled fine, but would not plane the boat. It turned out that the insulating sleeve on one of the shorting switch wires had slid back and whenever the magneto was advanced past start, the stop switch wire shorted against the engine block. . . 😀

[titantn]

A quick followup. I finally had time and good enough weather to go for test on the lake. She started easily and ran great. I really didn’t have a lick of trouble. It’s true it’s not the most powerful engine – I expected a little more from 10hp, but it did run smooth, start easy, idle easy, etc. My next issue to tackle is that the prop is dinged up and not in the best shape. Maybe a little improvement on the prop will help propel me slightly faster. Thanks again for all of your help.

[crosbyman]

maybe I missed it….. what was the basic cause of all this grief….coils carb wires crud, ……? …and tell it to that original mechanic who had no faith in oldies 😆

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[outbdnut2]

quote fleetwin:

Yeah, these engines don’t have a lot of power/top RPM….They start easy, idle nice, and are smooth, but aren’t going to win any races….
Try to take a video of the engine running on the boat if you can…

Yeah – these 9.5s were rated at the powerhead, as were the Mercury 9.8s. I’ve found these two motors perform about the same, and the Johnson 9.9s rated at the propshaft from the late 1980s and the Merc 9.9s from 1986 up will plane boats and run circles around the 9.5s and 9.8s. I’ve had them all on my 14′ aluminum rowboat for comparison.
Dave

[Mumbles]

Two different beasts here. The 9.5’s are trolling/fishing motors while the 9.9’s (detuned 15’s) were designed to get you somewhere in a hurry.

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