1974 6hp Evinrude Fisherman WOT very very sluggish!

[Cebmike27]

Hi y’all,

I have a 1974 6 hp evinrude fisherman. Everything was working fine until this last weekend when I took it out. Starts just fine 2 pulls open choke. However, when I was coming back in to trailer the boat. The engine seemed to not run on WOT. While on WOT it seems to be sluggish very sluggish. I hear it want to kick up in RPMs. Like if something is preventing it from reaching its proper RPMs. but it feels to me like it is stuck. Back home I ran it inside a barrel and it seems just fine. Seems to me it’s when it’s loaded it does this. Not sure what’s going on. I’m thinking of doing a carb rebuild, Please let me know your thoughts. Thank you!

 

[F_R]

Well it ain't the carb.

Two much more likely items are it is running on one cylinder. --Or-- The shock absorber in the lower unit is broken. That'll make it seem like it is seizing up.

 

[racerone]

No shock absorber in the 74 model when it left the factory.

 

[OptsyEagle]

Run a cylinder drop test. Fire the motor up and let it warm up. With an insulated pair of pliers pull one spark plug boot at a time. If the motor stalls when you pull a boot it means the other cylinder was not firing or is very weak.

Could be as simple as a fouled spark plug or could be dirty points and possibly a few other things. My main guess is that only one cylinder is firing. These motors will run remarkably well on only one cylinder but with significantly reduced power at the top end. Good luck.

 

[racerone]

Replacement head gaskets are better quality.-----Not sure what year they went to the metal rings.-----Compression test should be done.

 

[Crosbyman]

heat related ??? coil…. condenser... poor cooling ???


http://www.leeroysramblings.com/OMC_6hp.htm

 

[F_R]

No shock absorber in the 74 model when it left the factory.

Oops, yer right. I knew I screwed that one up, just hadn't gotten around to fixing it yet.

 

[Cebmike27]

Took out the spark plugs and this is what they look like.

 

[racerone]

Does spark jump a gap of 1/4" or more on both leads, yes or no.------That procedure is a maximum voltage output test for the magneto.----And post the results of a compression test.-----Testing is your path to a quick resolution of motor issues.

 

[oldboat1]

This for testing the magneto (about $10 at an auto parts store):




Test with both plugs removed, and make sure the tester has a solid ground.

Use Champion J6C plugs, gapped to .030. You might be due for replacement plugs — can’t tell from the pic, but if there is any rust you will need to resolve that (might need a head gasket). When you suddenly began having issues, was the motor overheating?

 

[Cebmike27]

No overheating.

 

[Cebmike27]

This for testing the magneto (about $10 at an auto parts store):




Test with both plugs removed, and make sure the tester has a solid ground.

Use Champion J6C plugs, gapped to .030. You might be due for replacement plugs — can’t tell from the pic, but if there is any rust you will need to resolve that (might need a head gasket). When you suddenly began having issues, was the motor overheating?


I will start with replacing the spark plugs and see what happens from there. Will post results. Thanks for all the help!

 

[Tim Frank]

I will start with replacing the spark plugs and see what happens from there. Will post results. Thanks for all the help!

I have never understood why people with motor problems come in here, ask for advice, and then ignore it in the rush to buy some parts to throw at the problem.

Racerone has explained the obvious first troubleshooting steps. no purchases necessary as Auto Parts stores will usually lend the compression gauge and spark tester....although buying them is a great investment if you are going to continue with DIY repairs.

If you have no compression and/or no spark, why spend even $10- on new plugs until those issues are resolved?

 

[jimmbo]

I have never understood why people with motor problems come in here, ask for advice, and then ignore it in the rush to buy some parts to throw at the problem. confused:


If you have no compression and/or no spark, why spend even $10- on new plugs until those issues are resolved?

Perhaps they are not hearing the answer that confirms what they have already made up their minds on. Happens all the time

 

[Cebmike27]

I have never understood why people with motor problems come in here, ask for advice, and then ignore it in the rush to buy some parts to throw at the problem.

Racerone has explained the obvious first troubleshooting steps. no purchases necessary as Auto Parts stores will usually lend the compression gauge and spark tester....although buying them is a great investment if you are going to continue with DIY repairs.

If you have no compression and/or no spark, why spend even $10- on new plugs until those issues are resolved?

And there it is. I’m not ignoring what anyone is saying on here. You don’t know what I’m doing or about to do. Just because I said one thing does not mean that’s what I’m going to do. I guess even On these helpful forums there are people that still start drama. Leave the drama for Facebook, please.

 

[southkogs]

Leave the drama for Facebook, please.

Good advice for all.

There's some excellent diagnostic direction given here for future readers, so no reason for anyone to get their manifolds in a wrinkle. If you want to buy plugs and put 'em in - go for it. You asked a question, and had three pretty knowledgeable guys answer give you good advice. You really didn't acknowledge that advice - just decided to get new plugs.

Give the plugs a whirl and report back in. If it works, that's great! If not, you've got other stuff to try.

 

[Cebmike27]

New spark plugs put in. Ran the boat this morning. Everything seems to be working as it should.

I apprciate everyone’s help and advice.

 

[Tim Frank]

And there it is....... Just because I said one thing does not mean that’s what I’m going to do. I guess even On these helpful forums there are people that still start drama.

Indeed, you are correct.
None of us have any idea what you are going to do, have done, or any other symptoms or issues that relate to your motor other than what you post.

Not sure why you consider any of this drama.

Seems like you got a satisfactory outcome; that is good news!