1958 35 hp Return to Service after 15 years

[Trackbolt]

I am in the process of returning my 1958 Bigtwin 35 hp (25936) Evinrude to service after about15 years in the garage. When I last used the motor in 1997 I finished off the season by squirting outboard motor oil in the cylinders through the two spark plug holes and slowly turning the flywheel a few revolutions by hand. Before that the carb was run dry. I have added a squirt or two of oil every couple of years and turned the flywheel. The motor is free and turns without effort. The points, condensers and coils were last changed out by me in 1983. I am planning on replacing them as well as the water pump in the next few weeks. This motor always ran well since it was new.
I guess I am asking is what more needs to be done to return this motor to service. I will be removing the head to inspect the cylinder walls and water passages. I also plan to convert it to a fuel pump instead of the pressurized fuel system too. I need to rebuild the pressurized tank tops and I don't want to put the time or money into doing that. I have a couple of old non pressurized tanks that can be used.

Thanks
Tony M.

 

[lindy46]

Re: 1958 35 hp Return to Service after 15 years

Sounds like you've got it covered. Don't forget to change the gear oil. How long since the carb was rebuilt and the fuel lines were changed?

 

[Trackbolt]

Re: 1958 35 hp Return to Service after 15 years

Sounds like you've got it covered. Don't forget to change the gear oil. How long since the carb was rebuilt and the fuel lines were changed?

I was going to rebuild the carb and already have the carb kit for that. Will get new fuel lines as I am changing from pressurized to fuel pump. I changed out the present fuel lines in the early '90's. Before that in 1983.

Thanks

 

[kfa4303]

Re: 1958 35 hp Return to Service after 15 years

Hi Track. This may help.

Reviving a Vintage Big Twin - Part 1

 

[64osby]

Re: 1958 35 hp Return to Service after 15 years

If you had replaced the coils, points and condensers I would leave them alone. You can inspect the coils and adjust the points with out pulling the flywheel.

Test your compression, if it's above 100 you should be good, 80 at a minimum.

The main concerns would be the carb kit and new fuel lines, new impeller, and change the lower unit fluid as others have said.

If it's not broken, don't fix it. My .02

 

[Trackbolt]

Re: 1958 35 hp Return to Service after 15 years

With decompression lever disconnected the motor posted 120 in each cylinder on four tests. Spark from both plugs was excellent.

 

[lindy46]

Re: 1958 35 hp Return to Service after 15 years

Sounds like you've got a good engine. With a little maintenance/tuning, it should run great!

 

[kfa4303]

Re: 1958 35 hp Return to Service after 15 years

+1 sounds good. Try removing the spark plugs and spraying a bit of 24:1 mix (5.5. fl. oz. of oil to 1 US gallon of 87 octane gas) into the cylinders, then replace the plugs and fire her up. Just be sure you only ever run the motor in a test tank with water filled up to 1-2 inches below the main exhaust port.

 

[Trackbolt]

Re: 1958 35 hp Return to Service after 15 years

I am sure it will run given compression and spark. I want to give the carb a cleaning and most of the linkage on the motor is encrusted with dried grease. As I was removing the air silencer to get the carb off I removed the high and low speed needle. The low speed has a nice taper and looks pretty good. The high speed needle is almost blunt. I seem to remember it always being that way and it always adjusted well without any problems. Can someone tell me what I am looking at. Is that blunt taper on the high speed needle normal for this model 25936? I just cannot remember.

 

[64osby]

Re: 1958 35 hp Return to Service after 15 years

Can't say on the blunt tip.

I would replace the impeller and do the carb and lines like you were planning. Then give it a tank test. After the tank test check the lower unit oil for water.

Sounds like an easy project getting it back on the water. :joyous: Any pictures?

 

[Trackbolt]

Re: 1958 35 hp Return to Service after 15 years

I am going to try a picture or two

 

[kfa4303]

Re: 1958 35 hp Return to Service after 15 years

Hi Track. Wow she looks great. The relatively blunt tip is normal on the hi speed needle, but the lo speed needle should have a very fine point. Here's a great link to an OMC carb reuild with both hi/lo needles. It's for a different model, but all the steps are the same. You can even get a carb kit right here at iboats for about $25.

5.5 HP Evinrude Johnson 1954-1954 Carburetor Tune-Up Procedure

http://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1958&hp=35&model=25937

 

[HighTrim]

Re: 1958 35 hp Return to Service after 15 years

The high speed needle is supposed to be blunt as stated. It is really just a faucet.

 

[Trackbolt]

Re: 1958 35 hp Return to Service after 15 years

A little update on my progress. The carb is disassembled and soaking in a can of carb cleaner. I poured the fog to it back at the end of the season in 1997 and the carb was oily but not covered inside with hardened shellac. The packing material and gaskets were flaking apart as to be expected. The needles show almost no wear so I am going to forego attempting to change out the seats and just let the cleaner and compressed air work its magic. The float is original cork and looks like it. That will get replaced as will the inlet needle. The carb kit and some packing for the needles should do the trick. I did not remove the welch plugs yet. I want to remove the one on top of the carb but I want to wait until I am certain that the kit includes a new one. I did find a four gallon pressurized tank in my shed that I picked up at a yard sale. I am going to leave the pressurized fuel delivery system in place and not change over to a fuel pump just yet. I have a line on a good 6 gallon pressure tank that I can get with a swap. That will save me a little time and money.

 

[lindy46]

Re: 1958 35 hp Return to Service after 15 years

I've never had any problems with the pressure tanks. Good choice on your part to stay with it. And you'll keep your motor original.