'61 Evinrude 40HP Revving but not accellerating

[dirwin7]

Hi All,

First time posting here. I'm not much of a mechanic but I still know my way around. I just bought a boat with a 61 Evinrude Lark 40 HP motor on it. Here's the problem. I took it out yesterday and I had no real problems with it other than it seemed like it was revving too high the whole time. Today I took it out and I have this problem.

Background info: The shifting cable is bent so it shifts into forward no problem, but it has a problem shifting "backwards" into neutral or reverse, so I disconnected it and I was controlling the shifting manually.

When I started the motor it immediately went forward like it was in gear, but it went forward slowly. Then when I manually shifted into forward while at the same time having the driver shift the shifter in forward I didn't hear it "engage". It still went forward but it continued to go forward slowly. When it was given more and more throttle it just revved higher and higher but it didn't go any faster. The best way I can describe it is if you are driving a manual car and you have the clutch half way out, you'll go forward but not very fast, and no matter how much gas you give it it won't go any faster.

I shifted it into reverse, and it went into reverse, but again, not very fast at all, like it really isn't actually engaging, but just somehow sort of half way.

I took it out of the water and started it up in a trash can. The same problem occurs, even though I give it more and more throttle, it doesn't translate into more acelleration. When I was done with running it in the trash can the water was incredibly dirty with oil on the top of the water. I cleaned a bunch of old oil off the engine just a few days ago b/c I just bought it so it may be the remnants of that, but like I say it was really dirty. Also, if there was old caked oil on the engine, it must have leaked from somewhere.

Has anyone experienced similar problems? Could this be a lower unit issue? Is this a prop issue? I just don't get it. Any help would be greatly appreciated, thank you all so much.

Dan

[lindy46]

Sounds like you have a spun propeller hub. The hub has a rubber bushing (which you can't see) which is designed to "give" if you hit something. This protects the prop and lower unit. On old motors, the hub rubber can deteriorate and slip, causing the problem you're experiencing. You can check for a spun hub by removing the prop and scribing a line (waterproof magic marker) across the prop and hub. Replace the prop and run the motor to duplicate the problem. Now, remove the prop and see if the line still lines up. If it doesn't, you have a spun prop hub. A prop shop or Johnnyrude dealer can have the prop re-hubbed for around $40.

[dirwin7]

Thank you, I suppose my question would be then why is it going forward if it is in neutral, it shouldn't be engaged into gear correct? If it is a spun hub, then that should only effect it if it is in gear I believe.

The prop turns while in neutral with a bit of a scraping sound, and doesn't when it is put into gear if that is any help.

Dan

[bullcity101]

It sounds to me that your shifting linkage is out of whack. When it is "in neutral" it actually is in gear or at least trying to go in gear which is why you hear the scraping sound.

[boobie]

Look at the stbd side of the exhaust housing and you'll find a rectangular plate. Pull that off and make sure that the linkage has not slipped and is hooked up correctly.