1975 evinrude 25 hp outboard need help!!!!!

[CCATRETT]

We just recently purchased a boat with a 1976 evinrude 25 hp outboard. We have replace the water pump, gearcase lube, new spark plugs, thermostat, and new gas/oil mixture. We can get it to run in neutral but once we put into either forward or reverse it shuts off... Any suggestion on what its could be????

 

[JB]

Re: 1975 evinrude 25 hp outboard need help!!!!!

Howdy, Ccatrett.

Welcome to iboats.

Did it run okay before the mass replacement of parts?

Quite often fixing what ain't broke breaks something.

Seeming to run okay with no load is most sick outboards' favorite trick on owners. Most likely you have only one cylinder making any power, and not enough to turn the prop.

 

[Daviet]

Re: 1975 evinrude 25 hp outboard need help!!!!!

Since this is a new engine to you, I would start with checking the spark and compression. Those two checks are easy and free to do and will give you a baseline on the health of your engine. If they both check out OK, move on to the fuel system. Check all hoses, fuel filter, fuel pump operation, may be time to over haul the carburetor.

 

[Monte1961]

Re: 1975 evinrude 25 hp outboard need help!!!!!

Agreed^

 

[CCATRETT]

Re: 1975 evinrude 25 hp outboard need help!!!!!

Thanks... Yes it was doing the exact same thing before and after we replace parts... its getting fuel, it has spark, it trys to start but will not start at times and when it does start as soon as we put it in to forward/reverse it will shut off... Any other suggestions would be great...

 

[Monte1961]

Re: 1975 evinrude 25 hp outboard need help!!!!!

Ok you say you did a compression check? If so what are the numbers? Will spark jump a 1/4" air gap using a spark checker? Is fuel pump getting sufficient fuel to carb? Was a Linc and sync done? These are all things we will need in order to assist you in getting you back on the water! Good luck and post results!

 

[jbjennings]

Re: 1975 evinrude 25 hp outboard need help!!!!!

We just recently purchased a boat with a 1976 evinrude 25 hp outboard. We have replace the water pump, gearcase lube, new spark plugs, thermostat, and new gas/oil mixture. We can get it to run in neutral but once we put into either forward or reverse it shuts off... Any suggestion on what its could be????

I'm with everyone else on checking spark with an actual air gap spark tester.
I just worked on my '75 johnson 25hp a few minutes ago. It had a bad driver coil under the flywheel. It's a goofy system, and my fix was to use some parts I already had to convert it back to a universal magneto.
It certainly sounds as if it is running on one cylinder.
Good luck,
JBJ