78 johnson 70 hp

[blue924.9]

hey all, first time user here so sorry if i dont do something right. i have a crestliner open hull with a 70 hp johnson with electric start and remote steering, according to the serial and model number it is a 1978, it has been siting for about 8 years in a shed, covered, and it has been winterized, oil in the bores, lower end and motor drained, i am now wanting to get it out of the shed it is in and get it running, what should i do to it, i am kinda figuring on new battery clean the fuel tanks ( the spare tanks have gas in them yet but the tank that is on and the rest of the fuel system has been drained i think) more than likely a water pump impeller just to be safe, i have been told they dont like to sit around for very long. anything else i should do or get? i already have the muffs but think i will just get a big plastic container with the garden hose flowing into it to cool the water to get it running, i will also maybe get a service manual but the previous owner thought he had one and more than likely some new spark plugs depending on what the old ones look like.


also if anyone can tell me anything about the motor, how dependable they are ect that would be great, thanks

 

[Daviet]

Re: 78 johnson 70 hp

Sounds like you have a good plan, make sure and fill the lower unit. If you run it in a barrel, make sure the water lever is about 6" above the water pump.

 

[175se]

Re: 78 johnson 70 hp

sitting for 8 years, id go through the carbs to play safe. JMO.

 

[boobie]

Re: 78 johnson 70 hp

Try and start it first and see what happens. After you have in the water of course.

 

[bonz_d]

Re: 78 johnson 70 hp

I'd go even farther, lay it down, pull the plugs and squit a little Marvel Mystery Oil into each cylinder and let it sit over night. Then slowly turn it over to oil the cylinders and rings. Then I would do a compression test. Then go through all the carbs and test for spark on all cylinders. When that all checks out then I would do the water pump. Check that out rea well as I thought there was a chance made in the impellar design.

I myself use both muffs and a barrel, the barrel ads backpressure and makes them run a bit better. Also quiets the exhaust noise.

Those old 3 cylinder engines have been around a long time and still run strong. One other thing to look at is that many have had a mod done to move the weep hole to the top of the cylinder head.