1975 Evinrdue 25hp

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Hello everyone.

I acquired a new to me, 1975 evinrude 25hp. Replaced the coils on it after I brought it home and replaced the water pump. When I viewed it, it idled ok in a tank.

I had to mess with it a lot to get it to idle the way I wanted it to, after that took it out to test it out.

It is running like garbage when put into gear, I could get out and swim faster than it pushed my 15 foot alumacraft. Seems like it is not getting enough gas.

(1) Seems like it is not getting enough gas, will not rev very high, therefore will not get up to speed.

Carb issues? Points Condensers?

Has good compression, really strong seems like, except when put into gear it jugs bogs down and seems to have no get up and go or power.

Other than that the motor seems to be in good condition, its pull and electric start.

Any and all input is greatly appreciated. Thank you.
 

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Have you rebuilt the carb? Assuming your running new gas since you got it idling good. Have you verified you have spark on both cylinders? Sometimes it will idle fine on one cylinder, but when you try to get up and go, it'll do what you're experiencing.
 
Are you judging the compression by the feel of it when you try to pull start or did you actually test it? It's possible it has great compression numbers, however, the cylinders may not be within 10-15% of each other. This would contribute to a rough idle. I'd warm it up, pull both plugs, ground the plug wires and do an actual compression test.

If this checks out, I'd then check the spark, then mess with the carb last.
 
I will pick up a compression tester this weekend, have to wait till after the 1st. Kind of on the govt boobie being a disabled veteran and all that jazz.

So I will pick up the tested this weekend some time and will do that as well as check to make sure I have spark.

I'm kinda bummed about the motor. I'm quite certain that the previous owner had to have known that this motor was not 100% but hey, now I know. I learned a lesson, but I hope it is not a very expensive one. I hope to have the engine running well enough for several years of use at least.

I've already spent around 150 bucks just on some new coils, impeller, fuel tank.

What would this engine be worth in good condition? 1975 evinrude 25hp long shaft?

Thanks again for all the awesome imput
 
Depends a lot on where you live, but up here, in good condition, I'd list that motor for about $600 and hope to get above $500 for it.

The compression check is going to give you the most information. Ideally if your above 100 psi /cylinder and fairly even, you'll be in good shape to repair it. Anything less than 80psi or with a wide variation of pressure would cause performance problems.

First off, replace the impeller. If needed, replace the water pump liner too. Obviously, the prior owner wasn't 100% honest with you, and you should not assume the impeller is ok. Far too critical to ignore.

Then I would remove the carburetor, pull off all of the movable pieces and blast air through all of the openings. Particularly the tiny little holes at the top of the butterfly valve. Blow these from the inside of the carburetor throat. Buy a can of carb cleaner and do the same thing. Make sure you really soak it. You're trying to blow any small particles away from these openings. One of these blocked will cause very poor performance just off idle.

Check the condition of the points. Make sure there isn't any pitting on the surfaces. If needed, clean or replace them. Also check the gap on the points. This will affect your ignition timing and needs to be set properly. When the arm of the points is lined up with the indicator on the point cam, the gap between the points should be 0.020".

Once you've got the points adjusted and the carburetor cleaned, you've hit two of the most common maintenance issues with these motors. Fortunately both are very inexpensive items to maintain. If you notice any difference in performance, then you know you're on the right track. If not, you may need to dig deeper into it to find what is wrong.

Good luck!
 
I support what kofkorn says. The good news is that a points and condensers ignition system is easy to work on and definitely the cheapest ignition system out there to replace. Shoot, I just had to replace the switchbox and stator on my 70hp Force and it was over $400. I was in so deep I went ahead and replaced the trigger as well which put me over $500 total.
 

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