1996 Evinrude 25 hp noise

I just purchased a 96 25 hp evinrude which came with a boat I purchased up in Minnesota and brought it down to Oklahoma. To me it has a louder than usual lifter noise. Any thoughts as to what it is and what I should do to either reduce or eliminate the noise? Thanx Jeff

Re: 1996 Evinrude 25 hp noise

Seeing as it has no lifters I'm afraid it may be a rod knock.
If you rock the flywheel back and forth you may here if its a rod.
Also you can pull the plugs and hold a pencil against the pistons and rock the
flywheel to see if the piston lags as you change directions with the fly wheel.
Piston needs to be in mid stroke to do the test.It will seem to lag slightly
at the top or bottom of the stroke.
Also a compression check may give an indication of motor condition.
From your follow up questions I suspect you may be an inexperienced mechanic.
We'll try to guide you through the the checks.
You could have a loose part rattling or the cover could be rattling.
Listening with a screw driver is an excellent suggestion.
Also a small hose will work like a stethoscope.

Re: 1996 Evinrude 25 hp noise

steelespike said:

Seeing as it has no lifters I'm afraid it may be a rod knock.
More to come.

Click to expand...

Is that bad??? I think these engines are a little noisy anyways?!

Re: 1996 Evinrude 25 hp noise

If it's a recoil start and the noise sounds like it could be coming from the recoil area, warm it up in barrel and shut it down. Remove recoil and start w/rope and see if the noise goes away. If not, an old mechanic trick is to put a large screwdriver to your ear - handle end - and probe different areas of powerhead to try to isolate the noise..

Re: 1996 Evinrude 25 hp noise

steelespike said:

Seeing as it has no lifters I'm afraid it may be a rod knock.
If you rock the flywheel back and forth you may here if its a rod.
Also you can pull the plugs and hold a pencil against the pistons and rock the
flywheel to see if the piston lags as you change directions with the fly wheel.
Piston needs to be in mid stroke to do the test.It will seem to lag slightly
at the top or bottom of the stroke.
Also a compression check may give an indication of motor condition.
From your follow up questions I suspect you may be an inexperienced mechanic.
We'll try to guide you through the the checks.
You could have a loose part rattling or the cover could be rattling.
Listening with a screw driver is an excellent suggestion.
Also a small hose will work like a stethoscope.

Click to expand...

I can say this for now...the compression on one is 125 and the other is 121....I do appreciate your input. I'm wondering if running a motor of this caliber with premium gas(due to they have nothing but ethanol in their gas in Minnesota) might be an issue with preignition...or detonation?:help:

Re: 1996 Evinrude 25 hp noise

I'm curious about the noise. Can you post a video?
Also, you may want to check youtube. They're some videos on this motor to give you
a sense how loud they are...
http://www.youtube.com/watch?v=t83vJ3OhJT8
FYI. You can still find non-ethanol fuel in Minnesota, but I never had need for it.

Re: 1996 Evinrude 25 hp noise

neumsky said:

I can say this for now...the compression on one is 125 and the other is 121....I do appreciate your input. I'm wondering if running a motor of this caliber with premium gas(due to they have nothing but ethanol in their gas in Minnesota) might be an issue with preignition...or detonation?:help:

Click to expand...

High test fuel is actually harder to ignite to resist the higher compression.A healthy motor would usually run on high test but might be fussy and may be ever so slightly reduced in power.