Used outboard maintenance

[Ybor-knight]

I just bought my first boat, it has an old 1978 Chrysler 115hp outboard.  I have seen the motor run, but I did not get to take it out on the water because it had no prop.  I now have a prop and I have a manual on its way that I found online so I just need to know what all maintenance should be done to a motor that hasn't been in the water in several years.  I'm sure the lower unit oil needs changing and I figured the water pump and plugs probably should be changed, but what other things would be recommended to be changed before taking it out for the first time?

[bassassasin260]

change the water pump impeller, change the lower unit oil and the engine oil and filter. and also get a new thermostat. other that you shoudl be fine. for a guy like myself who is more mechanically inclined id clean the carb also, but most people dont worry about it.

[sneaker]

I had a 85 HP chrysler on my Bayliner bass boat and it was an excellent engine. But I think your 78 model is a 2 stroke engine as was mine, so don't forget to add oil to the fuel as it is the only lubrication for the power head. Check you manual for the correct oil/gas ratio. I think mine used 1/2 pint  per gallon of fuel, or a quart for each 4 gallons of fuel.

If the engine has been sitting for a long time, the crankshaft seals between each cylinder will be dried out and will leak. This results in a engine that does not start or idle well. If you are lucky a few hours of operation they will swell to provide the needed airtight seal and you might get several years of use out of this engine.

Mine was as reliable as a stone and even when the water pump impeller failed miles from home, the motor would remain cool if I moved along at 25-30 mph, fast enough to create enough pressure at the water intake to circulate thru the engine. Sure did irritate the harbormaster when I blew in thru their 5mph water. He also cooled down when I told him about the problem.

[Ybor-knight]

Thanks for the advice.  I have the service manual now so I can look up the fuel mix ratio.  Unfortunately the manual did not include a parts list with part numbers so I've ordered that seperately today.  I want to make sure I order the correct impellar and apparently all the gaskets for the lower unit up to the water pump since you have to drop all of that to change the impellar.  I also need that part list to locate part numbers for the prop nuts and pins and everything that goes on after the prop.  I've been having difficulty locating all of that online so hopefully if I have the part number I'll have more luck.  The boat came without a prop or any of the mounting.

[fishfordollars]

First, welcome to the forum.

You may have a problem with the carburetors since this motor has not been run in a long while. Be sure you dispose of any gasoline that might have been left in the tank. Also check and clean or replace the fuel line so you will not pump any bad fuel into the carbs.

Good luck.