extending life of outboard

randyray41

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Any tips, techniques, recommendations for extending the life of an older outboard?
 
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racerone

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Add a bit more oil to the gas.-----Change the waterpump impeller every 5 years.
 

randyray41

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instead of 2.5 oz. of oil, how much is a "bit"? Ha, I change my impeller every other year, sometimes every year depending on how much I use it. Fairly cheap replacement. I take my 86 150 HP to mechanic, he charges me $90. The shift linkage screw is tough to get to.
My newest toy, is a 78 70 hp. evinrude it appears the thermostat housing have never been opened. Still looks like the green paint is intact from factory. Would it be good idea to change, im almost certain there is no over heat alarm. The p hole is tapped into the side of the water jacket cover? Cover on side of block. Will the water stream warn me if the t-stat sticks?
 
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racerone

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??---Well in 78 there was an overheat alarm.----And Evinrude has had overheat alarms on the bigger motors since the early 1960's !!
 

F_R

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Tell-tale stream comes out at the beginning of its flow through the powerhead. Tells you nothing about the thermostat, which almost the last thing the water sees.

Extend the life?? Keep it the heck out of salt water. Keep it the heck out of weeds. And NEVER let it run hot.
 

fhhuber

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A bit more oil: 40:1 instead of 50:1.... or adding 200:1 in the gas tank if you have auto-inject
(that 200:1 won't do a lot if the injection system fails, but will give you a few seconds more time to shut it down if the alarm goes off)

Much more and you'll create problems.

Draining the carbs/fuel system for the winter and using fogging oil. to protect the engine in storage.

Store it on a shed in a manner mice and bugs can't make it their home.
 

jakedaawg

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Easiest way to extend life beyond what they are mad for, besides regular maintenance, is to not run them. With that said, don't run full throttle. Find a decent cruise rpm. I know a friend who has a 25 yr old merc 175 in the keys. He has never flushed it. Leaves it in the water year round tilted down. Never runs it over 3500 and it still runs.

I live in Crystal clear spring fed water and I don't know of a single one still running up here.

Now, you need to understand that this guy makes his own luck. He raved boats for a long long time. He knows his stuff. Sure , he throws an impeller at it.and changes out the fuel lines. Yes.it's also an old Fairchild race block that's been retired, but he never does any thing more than put it on plane. It will prolly go to the island for another 20 yes. 175 is what's on the hood anyways ;)
 
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randyray41

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No Title

This is where the P hole is fitted on motor.
 

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David Young

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Any tips, techniques, recommendations for extending the life of an older outboard?

I have a 1977 70 hp Evinrude. Check the compression, this will give you an idea if your motor is worn out or not. Mine doesn't like to run on muffs or in a barrel for some reason. I had the overheat alarm go off once because i didn't have the muffs on right. I just changed my thermostat a few months ago. It runs great in the lake. Order the cork gasket, the housing gasket also order new poppit valves with new rubber grommets. When you remove the thermostat housing the spring loaded poppit valves will fly off :) I didn't know about them until i removed the thermostat cover :)
 
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Chris1956

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Rats, I disagree with Jake. I say run it a lot. A lot of problems are due to old fuel, especially if the motor is stored a lot. Use fresh fuel and use it up....Do the Preventative Maintenance of course..
 

ondarvr

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Running extra oil can increase carbon build up, which is one of the main reasons outboards die an early death.
 

redneck joe

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Outboard same as your physical body. Run a good speed, have plenty of fun, but balls to the wall all the time equals an early death. Change your impeller, eat fiber. Get drunk on weekends only. WOT couple time a year to clean her out. Regular exercise keeps joints in good shape. Change your LU oil. A hug every now and then wont hurt.
 

interalian

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Outboard same as your physical body. Run a good speed, have plenty of fun, but balls to the wall all the time equals an early death. Change your impeller, eat fiber. Get drunk on weekends only. WOT couple time a year to clean her out. Regular exercise keeps joints in good shape. Change your LU oil. A hug every now and then wont hurt.

QFT!
 

randyray41

Petty Officer 2nd Class
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May 31, 2011
Messages
123
I have a 1977 70 hp Evinrude. Check the compression, this will give you an idea if your motor is worn out or not. Mine doesn't like to run on muffs or in a barrel for some reason. I had the overheat alarm go off once because i didn't have the muffs on right. I just changed my thermostat a few months ago. It runs great in the lake. Order the cork gasket, the housing gasket also order new poppit valves with new rubber grommets. When you remove the thermostat housing the spring loaded poppit valves will fly off :) I didn't know about them until i removed the thermostat cover :)



What should the compression run? 120 is compression on all 3 cylinders
 
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jakedaawg

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Rats, I disagree with Jake. I say run it a lot. A lot of problems are due to old fuel, especially if the motor is stored a lot. Use fresh fuel and use it up....Do the Preventative Maintenance of course..

I was being sarcastic with the first part about not using it. Tongue in cheek or so to speak. The second part I feel is absolutely true. That merc gets run at least three days a week though.
 

nabiul

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Jul 18, 2015
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Take it to canada at the end of it's life and sell it on kijiji for near new price and then buy a new one.
 

David Young

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Jul 12, 2015
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What should the compression run? 120 is compression on all 3 cylinders

I went down to my local car parts store and rented a compression gauge. You pay a deposit but you get every cent back when you return it. It was beat all to heck, i got 115 to 120 on all three cylinders. From what i've read, as long as the cylinders read within 10 or 15 (can't remember) percent from each other they are good. You don't want (for an example only) two cylinders at 115 and one at 40 :(
 

Fed

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By the book link & sync and correct prop is all I can offer.
 
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