1977 25hp Evinrude bogging down-Help

tiger5

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Nov 9, 2008
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I have cleaned the carb 3 times and have checked the filter. Motor starts good, but when I give it the gas will not come up to speed, any suggestions.
Thanks, tiger5
 

Joe Reeves

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Re: 1977 25hp Evinrude bogging down-Help

If you have proper compression and spark, either the timer base under the flyheel is sticking, the throttle butterfly is opening too soon, or you're overlooking something within the carburetor. Have you manually cleaned the high speed jet?
 

tiger5

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Re: 1977 25hp Evinrude bogging down-Help

I took everything apart on the carb and cleaned with carb cleaner and air, I don't think I missed anything. I am getting spark, but I have not checked the compression. I'm not sure about under the flywheel. Thanks, tiger5
 

jbjennings

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Re: 1977 25hp Evinrude bogging down-Help

If it has that pesky fixed jet, then you have to get it spotlessly clean. You may have to really soak it. Also, when Mr. Reeves said check the spark I believe he meant with a spark tester to see how wide of a gap it would throw a spark across. It should cross at least a 1/4 inch gap to work under compression. what does your compression look like?
good luck,
JBJ
 

tiger5

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Re: 1977 25hp Evinrude bogging down-Help

Did not get a chance to check compression yesterday, but try to check it today. Don't have a spark checker. Will post later. Thanks, tiger5
 

outlaw241

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Re: 1977 25hp Evinrude bogging down-Help

not sure if your model has a nozzel gasket but it could be the problem,it a small gasket ithe carb bowl goes up through center of float ,if its bad it wont pick up fuel at high rpm it will suck air above float,very cheap an easy fix
 

tiger5

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Re: 1977 25hp Evinrude bogging down-Help

I checked the compression and the bottom was 95# and the top was 100#. The checker that I used, I could only tighten by hand so I'm not sure if was seatting good enough? Thanks, tiger5
 

tashasdaddy

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Re: 1977 25hp Evinrude bogging down-Help

compression with in reason. sounds like a link n sinc is needed.
 

tiger5

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Re: 1977 25hp Evinrude bogging down-Help

Sorry, don't know what link n sinc means. Thanks, tiger5
 
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