bought a johnson 115hp...

[greghennings]

Hello all, just joined the forum to figure out which way to go with the Johnson 115 i bought.

I'll post pictures, my main concern at the moment is the lower unit has "pitting" on the gear housing. And some on the upper body. Before i go in any direction, i need to determine if this is usable or not. Little upset with myself about it because i didn't see it until i brought it home, the bright sunlight must have masked it. I've drained the gear oil, only to have about a cup of water come out first, followed black oil. There were no metal shavings in the oil thankfully.

Also real quick the model number is 115ETL78C, i got the 115hp 1978 part, but what does the ETL and the C stand for?

Thanks guys!

 

[racerone]

Re: bought a johnson 115hp...

The lower unit appears to be a lot newer than a 78 model.

 

[oldboat1]

Re: bought a johnson 115hp...

Is this a salt water motor? It looks to me like s.w. pitting and/or pitting from electrolysis in a marina. It looks like the pitting was painted over. None of that means the motor is no good. Do you have a little of the history from the seller? On the oil, it sounds to me like the motor was sitting unused for a while before you bought it. The water in the gearcase separated from the oil and settled to the bottom of the gearcase, rather than giving you that nice milky emulsion you would otherwise see. You do have water in the gearcase, though, and that gets fixed with resealing. Anyway, those are my guesses from looking at it. I can't tell what year the unit is, so will trust Racerone on that. There will be some maintenance and repair, and more testing...

 

[boobie]

Re: bought a johnson 115hp...

Pressure and vacuum check the gear case before you take it apart. That way you'll know exactly where the problem is.

 

[greghennings]

Re: bought a johnson 115hp...

Very good points guys, the P.O. told me that he thought the motor was an 86, so you can imagine my disappointment when I looked up the model number to find out its a 78. The only way I was able to determine that is by my model number 115etl78c. I couldn't find a serial number page that matched the number I have, J4977695.

The p.o. also told me that he never had the motor in the water, he bought a boat, and never got around to fixing it up. He did tell me the engine ran, I checked for compression and got something on all cylinders. I do know that I need to warm the motor up to get accurate results, that just wasn't an option at the time of purchase. other than that, I don't know where this thing has been.

From my research I found that model number is a salt water motor. and I would agree, the pitting does look painted over. I wouldn't doubt this motor sat in water a lot. notice the anode bars are really eaten up.

I can pressure and vacuum test the lower unit, but I do know the propeller seal is bad, I noticed water under the skeg, that's when I drained the lower unit.

 

[oldboat1]

Re: bought a johnson 115hp...

might have had the lower unit replaced (Racerone's note, above). Should keep that in mind for parts, although may make no difference. In buying an impeller, for example, it might be good to buy the first one at a dealer and in person (assuming you will do the work yourself), taking the old one with you to make sure you have a match. Probably shouldn't be disappointed over the year -- condition/prior use and maintenance more important. Just check it out until you know what you have.

 

[greghennings]

Re: bought a johnson 115hp...

so far looks like positive reviews, my main concern is it structurally sound to operate. could a guy have a metal shop tig weld in those pits? as long as no metal flake came out with the oil, I think I can get away with just doing a new seal and replace the water pump for good measure. I wanted to take the whole thing apart but I guess that's a big no-no.

on to the engine, I want to run the engine but I don't know if I dare put water in it because at least the next week calls for single digit lows. Its in a shop, but not heated all the time, most of the time its in the 20's, unless I fire up the wood furnace. how long could I run the engine to warm up to check it over?

 

[racerone]

Re: bought a johnson 115hp...

The metal in the gearcase is fairly thick.---Those pits are the least of your worries on this motor.----Post results of a compression test.---Post pictures of the powerhead.

 

[oldboat1]

Re: bought a johnson 115hp...

another point or two -- will need a manual for the motor if you don't already have one. Also, expect addit. corrosion in bolts, fasteners, etc. based on appearances (lower unit). Nice not to break off bolts if it can be avoided. If it were mine, I would make sure there was oil in the lower unit before testing/running, even if it's got some leaks you will eventually fix. First test should be a compression check, but really shouldn't spin the motor unless the lower unit is in water (no sense risking any addit. damage to the old impeller in there). (That's not to say I wouldn't do it on mine, but wouldn't tell you to do it on yours!) Air temp. isn't really a problem -- probably more of a prob. for you than the motor. Running it inside the garage is definitely a problem for you too, but can check out compression to see what you have (plugs out and grounded).

 

[greghennings]

Re: bought a johnson 115hp...

I got it just temporarily hooked up to run, little bit of choke and fired off! I only let it buck for a minute, she got warm fast! Also, i had some fresh 80w-90 oil left over i put in the LU just to be safe, if anything else to flush out some of that crud. Uh, anyway compression test... looking at the back of the motor, upper right 95-100, lower right 115, upper left 113, lower left 113. Not to shabby i guess, that upper right i triple checked, worst i got was 95 best i got was 100, i think the first one was low because i didn't have the throttle all open.

It really didn't run that bad but it did hint at some misses, my gas is also from last summer. I'll probably take the carb's apart anyway make sure they're gunk free.

 

[greghennings]

Re: bought a johnson 115hp...

almost forgot more pictures...i'm just really glad not to see any mouse poop or chewed on wires..

 

[boobie]

Re: bought a johnson 115hp...

Racer, why do you say a lot newer than a '78 on the gear case ??

 

[oldboat1]

Re: bought a johnson 115hp...

upper right cylinder is a little low, but might get a little better with use. might run a little rough, but could even out -- fresh gas and 50:1 mix, as you know. Don't go to a richer mix to try and compensate, as that will just foul plugs. I would say worth pulling the lower unit and reworking water pump, but see what the other opinions are on compression findings.

 

[racerone]

Re: bought a johnson 115hp...

The sacrificial anode was not used in the 1978 model year !!----Throttle position does not matter when doing a compression test on this motor !-----Should pull the bypass cover for the low cylinder , will only cost you some time and a 99 cent gasket.

 

[greghennings]

Re: bought a johnson 115hp...

The sacrificial anode was not used in the 1978 model year !!----Throttle position does not matter when doing a compression test on this motor !-----Should pull the bypass cover for the low cylinder , will only cost you some time and a 99 cent gasket.

i'm on it, whatever it takes to get this baby running top-notch. now that i've got some confidence in it i'm in full repair and replace mode. Very possible that the lower unit had been replaced, are there any other things that stand-out as being "not-78"?. Be nice to know i guess.

I've got the carbs torn down, not looking to shabby, a little cleaner, some new gaskets, should clean up real nice. Some new fuel hose, fuel filter had some gunk in it, diaphragm looked good, probably still replace it. I think next weekend i'll take down the LU.

 

[greghennings]

Re: bought a johnson 115hp...

hey guys, i've been slowly pecking away at this motor, i've got the lower unit taken down and taken apart a little bit, just enough to replace the drive shaft and prop seals. I've been cleaning it up too, amazing how much filth on it, some carb cleaner and the thing looks brand new! I've got a bunch of parts ordered, one thing on my list i'm not sure to order or not is a new thermostat. I haven't taken it apart yet, and there doesn't appear to be any gaskets for it leaking, should i tear this open and replace it? Also, what would it hurt just to remove the thermostat completely and let it pump water all the time?

And good call racerone on letting me know that lower unit was not a 78! Very subtle differences between the two but different enough you have buy specific parts for the 78, 79 to mid 90's? are all the same. Not to mention parts for 79 are half the price of a 78.

 

[emdsapmgr]

Re: bought a johnson 115hp...

You need to run that engine with thermostats. It has dual thermostats-one for each head. You'll need two thermostat housing gaskets, too. When you are in the housing, check the nylon pressure-relief valves to be sure they are not heat deformed. Possible the gearcase is a replacement. The later cases (somewhere around 81 or so) had the skeg with a more "swept-back" appearance. The addition of the sacrificial anode came out in 1982. Check for parts on the factory exploded parts diagrams: epc.brp.com

 

[greghennings]

Re: bought a johnson 115hp...

Well I'm gaining on the motor, got a lot of seals and gaskets replaced and got to fire it up today, ran ok. new water pump pushes water out like a fire hose, the old one was burned up. noticed that my tachometer doesn't work now. It did work with my old evinrude, I don't know how to troubleshoot this thing. From what I've read the rectifier could be bad? Is there a measurement on this a guy could take with a volt meter?

 

[boobie]

Re: bought a johnson 115hp...

You have to have a peak reading volt meter or else a volt/ohm meter with a DVA to check it properly. Meaning the signal on the gray wire.