2 cycle stored for 20 years

[Yardwork]

I knew this motor would be in storage for a long time so I poured motor oil into the spark plug holes and cycled the engine it a time or two...not sure that was smart but now I want to get it running again. I pulled the spark plugs and cycled the engine again and it turns over freely. Why should I do next? Do I pull it apart, do I tip it upside down and try to drain it? Do I take it to a mechanic shop for a professional to take apart and clean?

 

[Captain Caveman]

Pour some fresh 2-stroke gas in the tank and fire it up!

It will burn off the oil in the cylinders. The only thing that I would do prior to firing it up is drop the lower unit and replace the impeller. The rubber has probably dried by now.

 

[GA_Boater]

What motor?

I would check compression and spark, then try to fire it up.

I wouldn't worry about the impeller until I know it runs. All you need is a short run without overheating. Feel the block and shut it off when it starts to feel warm, it won't take long. Don't rev it up if it starts.

After you know it runs, rebuild the carb(s) and do the impeller.

 

[Yardwork]

Great help, thank you both! The compression in a concern, not sure where the oil ended up and that could cause pressure...is causing high pressure.

This is a 2003 Nissan 25hp, 2-cycle

 

[GA_Boater]

Pull the rope a few times with plugs out and the excess oil will squirt out. Watch your eyes.

 

[Sea Rider]

Depending on how much motor oil was squirted into eah cylinder, when cranking up the motor some oil will exit through the spark plugs orifices and some through the exhaust port, go down the lower leg and exit through the prop as well. Once sufficiently warmed up, go for a wot run as if stealing the combo for at least 5 minutes. Did you know that can pass that 25 to a 30 HP for peanuts cost....

Happy Boating​

 

[Yardwork]

After cleaning and changing the lower oil I fired it up. It will smoke a little until the oil from storage is fully cleaned out.

 

[Sea Rider]

Good to read that fired right up fast. Which type of watercraft and how loaded will be powering that motor ?

Happy Boating​

 

[GA_Boater]

Ah, satisfied customer #27! LOL

Don't forget about changing the impeller. It's probably in pieces.

 

[Sea Rider]

Ah, satisfied customer #27! LOL

Don't forget about changing the impeller. It's probably in pieces

Won't find an OEM Tohatsu impeller broken in pieces, at the most hardened but still pumping a good water flow up powerhead. That's due to being made with an elastomer which is bullet proof compared to traditional rubber impellers found in different motor brands. But will be healthy to check the current condition...

Happy Boating​

 

[Yardwork]

The impeller is on my list. I noticed that it was still producing a good flow though. This 25hp Nissan will be pushing a 204pound, 1959 Alumacraft FD. This particular hull is rated for a 35hp but I think the 25hp tiller is big enough on this boat. I'm finishing up the trailer restoration setting up new bunks and will start on the boat transom wood replacement this week. I should have this rig in the water by May.

 

[Yardwork]

I went to the Nissan web site to get the OEM water pump kit and the site said it was down for repairs...Where do I find OEM for a Nissan 25hp 2cycle short shaft, pump part number (361873220M)

 

[Faztbullet]

That not true as the same manufacturer in Italy supplies impellers for Nissan/Tohatsu/Yamaha/Suzuki/Mallory. I highly doubt they change the rubber compounds

 

[Sea Rider]

Take advantage when ordering spare parts to order the carb's gasket for the 30 HP motor. To know, both 25 and 30 HP motors shares the same CC powerhead, being the 25 carb and timing advance restricted. Can pass that 25 to a 30 in less that 30 minutes. ​

30 Carb Gasket : https://www.boats.net/product/tohatsu/346020110?ref=2fb302a685c678a1ce81fe120ffe58ca9fa4b090

Impeller : https://www.boats.net/product/tohatsu/345650210?ref=39e0e7b0a8e6368adcf7d04fe0643a0e4ddc9539

Check if will need the water pump's gaskets and the liner condition as well ?

Happy Boating​

 

[Yardwork]

Take advantage when ordering spare parts to order the carb's gasket for the 30 HP motor. To know, both 25 and 30 HP motors shares the same CC powerhead, being the 25 carb and timing advance restricted. Can pass that 25 to a 30 in less that 30 minutes. ​

30 Carb Gasket : https://www.boats.net/product/tohatsu/346020110?ref=2fb302a685c678a1ce81fe120ffe58ca9fa4b090

Impeller : https://www.boats.net/product/tohatsu/345650210?ref=39e0e7b0a8e6368adcf7d04fe0643a0e4ddc9539

Check if will need the water pump's gaskets and the liner condition as well ?

Happy Boating​

I looked up the impeller link and ordered it with gaskets due to the age of the motor and 19 years in storage. Thank you for the link

 

[Sea Rider]

I looked up the impeller link and it does not show that it comes with gaskets, is that a problem? This is a 2002/3 motor that has been in storage for over 18 years.

The gaskets should be ordered separately, are number 31 / 32 :​

https://www.boats.net/catalog/tohatsu/2003/m25c3-2-stroke-tohatsu/transmission-water-pump

If both gaskets are good to go, are not cracked, hardened keep the originals installed. Assume that 25 horse has low hour use ?

Happy Boating​

 

[Yardwork]

Separate question, the motor is mounting on a 14', 1959 AlumaCraft FD, How can I best protect the transom when the boat is on the trailer? Should I put a boot brace on the motor, take the motor off, what is best practices?

 

[Sea Rider]

Separate question, the motor is mounting on a 14', 1959 AlumaCraft FD, How can I best protect the transom when the boat is on the trailer? Should I put a boot brace on the motor, take the motor off, what is best practices?

Usually must sit fully vertical once on trailer to drain any water remaining inside.

Happy Boating​

 

[eterry]

I had the same boat with a 20 HP Chrysler. I strapped the motor to the transom so it couldn't move on the transom while xporting, worked for 10 years.

 

[Sea Rider]

That not true as the same manufacturer in Italy supplies impellers for Nissan/Tohatsu/Yamaha/Suzuki/Mallory. I highly doubt they change the rubber compounds

The Tohatsu impellers I have in stock says Made in Japan, no way that honorable people like them are repackaging impellers made in Italy as being manufactured in Japan. ​

This is an example of a Tohatsu impeller made with an elastomer compound compared to plain rubber ones, need no further clarification as the superb quality speaks for itself.​

Happy Boating