1976 evinrude 25hp problems...need some help

[meier247]

I bought a 76 25 hp evinrude from a guy and he said it had no spark. Took it home cleaned the coils up and everything had awesome spark and put her on the tank and it ran awesome. So we shut it off as my dad was going to take it out on the river for a test run the next day. He took it out said it ran good but when you go to idle it down it wont idle it dies. What causes that??? does it need a adjustment on the idle? or what. Please note im not very good with these boat motors lol. Also he ran it up the river and when and went to turn around it died and he couldn't get it back started. It was flooded out really really bad running carbon and the gas oil mixture was running down the lower unit down the sides. My questions is what caused this. Did the float stick on it? Also would buying a carb kit and cleaning it up really well help this issue? And what can I do with this idle issue? I have another questions also sorry for all the questions but I have heard of people running sea foam through there engines. I want to know if its a good idea to run it in there to clean it out or not. I have heard of people doing it saying there engine ran awesome afterwards then I also heard people saying do not run It through there as it it is bad for it. I need some help people!! Any reply and help would greatly be appreciated. Thanks so much in advance!

Michael

 

[pn]

Re: 1976 evinrude 25hp problems...need some help

you could test your float needle by pumping the priming bulb, if needle is stuck open gas will spew out the carb or back into the manifold depending on your tilt. and your primer bulb will never get hard. could be a reed vavle...
i like using a 50/50 seafoam/gas mix and shooting it in the carb while on high idle. i like the white smoke smell.

 

[meier247]

Re: 1976 evinrude 25hp problems...need some help

you could test your float needle by pumping the priming bulb, if needle is stuck open gas will spew out the carb or back into the manifold depending on your tilt. and your primer bulb will never get hard. could be a reed vavle...
i like using a 50/50 seafoam/gas mix and shooting it in the carb while on high idle. i like the white smoke smell.

Any thoughts on the idle issue?

 

[lindy46]

Re: 1976 evinrude 25hp problems...need some help

Buy a carb kit and clean/rebuild the carb. And make sure you remove the welch plug on top of the carb and clean the idle circuit beneath it.

 

[gm280]

Re: 1976 evinrude 25hp problems...need some help

Yes everything you posted about is the cause of fuel delivery system. So like previously stated, buy a carb rebuild kit and remove the carb and clean it and rebuilt it. The idle problem will probably be gone when you get everything finish. You can easily search these forums for exactly how to rebuild your carb, and then just follow the directions. It is not hard to do and actually considered regular maintenance work on most OB engines... Also not knowing the last time somebody changed the water pump Impellor, you should buy a water pump kit as well and change it too...and the lower foot oil while you are at it. All these things are regular scheduled maintenance issues that you WILL have to learn how to do or pay somebody else to do them if you own an OB...

 

[AlTn]

Re: 1976 evinrude 25hp problems...need some help

just to add..follow the tiller handle to its end and there should be a screw directly behind it that acts as a throttle stop/idle speed adjustment...if it hasn't been replaced it's made of plastic with a spring to serve as a tensioner...I've used seafoam with good results