1997 Evinrude 25 model E25RMEDC

[willocreek1202]

Changed out complete water pump housings twice, had a heck of a time getting water flow. Motor still runs hot and runs like crap popping and such. Did compression check and got 120 on all three cylinders. I also pulled the thermostat and I don't feel this is the problem. Any suggestions?

 

[nwcove]

Re: 1997 Evinrude 25 model E25RMEDC

did you put the tstat in hot water to see if it is opening? what do the plugs look like after a run? black? brown? whitish grey? sounds more like the water jackets are partially plugged tho. ( was the old impeller missing vanes when you did the first change?)

 

[willocreek1202]

Re: 1997 Evinrude 25 model E25RMEDC

I just ran it with the thermostat out and it pees a week stream and gets hot, pre detonation results in back fire to the carbs.
The water pump that I first pulled out was fried from what to me looked like running without water. I have used this engine for about a year and it has always been perfect. I do fish Florida lakes and partial plugging can be a problem. I have back flushed that connects at the pee indicator. My feeling is that it's plugged between the pump and inlet to the head. Suggestion how to check this area? I don't really want to pulled the head. I have ran it for a short time with the thermostat housing out and don't get enough water flow to even spill water out there.

 

[jasper60103]

Re: 1997 Evinrude 25 model E25RMEDC

Have you tried flushing it from the bottom up?
I connected a garden hose to the water tube with some duct tape
and turned on the water with low pressure.
(Yes, the duct tape holds well enough for a short time.)

Here's a video of the water pump test...
http://www.youtube.com/watch?v=xAJfBKNs7bo

 

[willocreek1202]

Re: 1997 Evinrude 25 model E25RMEDC

I found when I pulled the lower off that the discharge of the water pump was smashed. see attached. This also had a rubber bushing that was inserted and was almost pinched shut. I was able to salvage parts and made it work. Overheating problem is fixed.
Now my problem is what sounds like compression being released though the carburators and blows smoke out around intake area. I'm wondering about reeds? Maybe got to hot?

 

[willocreek1202]

Re: 1997 Evinrude 25 model E25RMEDC

Anyone with suggestion on the backfiiring thru the carbs?

 

[Johny25]

Re: 1997 Evinrude 25 model E25RMEDC

If it is back firing back through the carb I would definitely check the leaf valves. Sounds like you have a stuck leaf that is not seating properly or a broken one possibly

 

[willocreek1202]

Re: 1997 Evinrude 25 model E25RMEDC

I have the same feeling. I have also found that my motor is actually a 1996 and now know why the water pump that I ordered was the wrong part.
I am going to changed out the fuel and add a fuel additive to see if the leaf valves are just gummed up from this winter.