1979 Evenrude 115 Outboard

[gearyg]

Hello, last week I took my boat out and forgot to remove the rabbit ears (used for the hose) from my lower end which were blocking the pick up ports. In the 5mi zone, my engine overheated (only because an alarm buzzer went off). However, as I moved faster, the force of the water pushed the rabbit ears off and wather began to flow and cool the engine. Question: how can I know if this incident caused any damage to the motor....any input would be great....thanks.

 

[ezeke]

Re: 1979 Evenrude 115 Outboard

You could run a compression test.

The most likely thing would be that you overheated the cylinder heads enough to blow a head gasket, which might be indicated by the compression test, or by water intrusion into the combustion chambers.

In any event, retorque the cylinder head bolts now, and keep an eye on the spark plugs - they should all look about the same.

 

[KYHunter2]

Re: 1979 Evenrude 115 Outboard

Im surpised the ears held on so long.

After following the above advice .

If everything checks out , OK. Great.

Now its time for a water pressure guage.

IMHO, a must have, to prevent things like this from happening.

As well as monitoring water pump condition.

KYHunter

 

[gearyg]

Re: 1979 Evenrude 115 Outboard

Thanks for the advise, how would the compression test result if there were damage, would there be significantly less in one cylinder or all four. Right now, I have 120 in number 1&2 and 130 in 3&4....thanks again.

You could run a compression test.

The most likely thing would be that you overheated the cylinder heads enough to blow a head gasket, which might be indicated by the compression test, or by water intrusion into the combustion chambers.

In any event, retorque the cylinder head bolts now, and keep an eye on the spark plugs - they should all look about the same.

 

[gearyg]

Re: 1979 Evenrude 115 Outboard

Also, forgot to ask...what is IMHO?

Im surpised the ears held on so long.

After following the above advice .

If everything checks out , OK. Great.

Now its time for a water pressure guage.

IMHO, a must have, to prevent things like this from happening.

As well as monitoring water pump condition.

KYHunter

 

[ezeke]

Re: 1979 Evenrude 115 Outboard

Those compression numbers would not concern me in regards to the overheat incident.

They would make me wonder why the two cylinders fed by the top carburetor are lower than the bottom pair. Even so, I would be happy with those numbers.

Have you decarbed the engine lately?

 

[OBJ]

Re: 1979 Evenrude 115 Outboard

IMHO = In My Honest/Humble Opinion

#'s 1 and 2 = 120psi while #'s 3 and 4 = 130psi.

If the above compressions have been holding, I would suspect any sustained compression drop as something wrong.

Just a question....when was the last carb overhaul done?

 

[Theoutdoorsman]

Re: 1979 Evenrude 115 Outboard

gearyg............. Just a little heads up, when you get things squared away again, be sure and decarb that powerhead. In case you are not aware of it, and although these are great motors, these older crossflow engines are notorious for carbon build up, especially with todays fuels. If left unattended, it can lead to stuck piston rings which will eventually cause them to break and obviously cause serious internal damage to the powerhead. It appears, just judging by your compression test results, your in pretty good shape. But I would certainly make the use of SeaFoam (available at your local NAPA) a part of your preventative maintnance program. Go to the "Frequently Asked Questions" forum and look for a topic on decarbing. You'll be glad you did. Trust me, I just finished rebuilding my 1979 Evinrude 140 due to the carbon build up. Just wanted to give you some friendly advice and help save you, and others, the misery. Sure wish I'd have found this forum $1500 earlier........ d ........... This post may be a little off topic, but I thought it best to run it by you regardless. Best of luck to you!!!

This should save you some time on your search for decarbing. Click here.... http://www.iboats.com/bbboard/bbBoard.cgi?a=viewthread;fid=36;gtid=1035563

If you don't have a service manual, take a look here.....http://cgi.ebay.com/ebaymotors/1979...320031379731QQihZ011QQitemZ320031379731QQrdZ1

If you want to look at some exploded views and get some part numbers on those carbs, click here.............. http://www.evinrude.com/en-US/Accessories/Engine.Diagrams.htm

The decarb may actually free those rings in the lower compression cylinders and bring them back up even with the other two. If it doesn't, I'd follow OBJ's hunch and look closely at those carbs. It's really not a bad job to remove, clean, and replace the carbs. Plenty of help from the folks at iboats to get you through it. You won't find a better forum.......... period!!!................... ALAN

 

[Joe Reeves]

Re: 1979 Evenrude 115 Outboard

1979 115hp Evinrude...... curious if you're listing the cylinders properly. Standing in back of the engine, the cylinders would be as follows:

2.....1

4.....3

If your numbering is correct, you have 10 psi difference between the top and bottom cylinders on both banks. That would indicate that the top carburetor is running lean which in turn is causing piston, cylinder wall, and/or piston ring damage. If this numbering is correct, It would be a good idea to remove, clean, and rebuild the carburetors (both) if you haven't already done so.

If you numbering is incorrect, that difference being on one bank instead of both would usually indicate a faulty head gasket.

Cylinder head bolt torque would be 18 to 20 foot pounds in the following sequence:

9.....10

5.......6

1.......2

4.......3

8.......7

When checking the spark plugs, if any traces of water appear, I'd suggest you remove the heads, clean all sealing surfaces, and install new head gaskets.

 

[gearyg]

Re: 1979 Evenrude 115 Outboard

That is actually my winter project. I was going to strip them down and clean them up, would you recomend to use a rebuild kit, or will full cleaning be sufficient...

IMHO = In My Honest/Humble Opinion

#'s 1 and 2 = 120psi while #'s 3 and 4 = 130psi.

If the above compressions have been holding, I would suspect any sustained compression drop as something wrong.

Just a question....when was the last carb overhaul done?

 

[gearyg]

Re: 1979 Evenrude 115 Outboard

Ok, you have a point, when I am standing in the back of the engine, I am numbering the cylinders as follows...

1 3

2 4

1&2 being the higher 2 cylinders of the 4. Thus, I am incorrect in numbering the cylinders. The correct analysis of my compression test would be numbers 2&4 would be 120psi and 1&3 are 130psi based on correct numbering of the cyclinders. In this case, it appears I need to re-torq the head bolts in the order that you perscribed.

I am also going to do a De-Carb, I just got some Sea Foam "Deep Creep". Just a Question, how "much" do I spray into the cyclinder heads through the spark plug holes and let them soak?

Thanks again to everyone for great advise....

1979 115hp Evinrude...... curious if you're listing the cylinders properly. Standing in back of the engine, the cylinders would be as follows:

2.....1

4.....3

If your numbering is correct, you have 10 psi difference between the top and bottom cylinders on both banks. That would indicate that the top carburetor is running lean which in turn is causing piston, cylinder wall, and/or piston ring damage. If this numbering is correct, It would be a good idea to remove, clean, and rebuild the carburetors (both) if you haven't already done so.

If you numbering is incorrect, that difference being on one bank instead of both would usually indicate a faulty head gasket.

Cylinder head bolt torque would be 18 to 20 foot pounds in the following sequence:

9.....10

5.......6

1.......2

4.......3

8.......7

When checking the spark plugs, if any traces of water appear, I'd suggest you remove the heads, clean all sealing surfaces, and install new head gaskets.

 

[Theoutdoorsman]

Re: 1979 Evenrude 115 Outboard

gearyg........Wise decission on the decarb. Just follow the link to the decarb process and follow it to a "T". Give 'em a good soaking. I'd say a four to five second blast in each plug hole should do the trick for soaking overnight. Just be sure to reinstall the plugs afterwards. You may have to replace the plugs when the process is finished. I'd recommend you do, especially if it's been a while anyhow. The service manual on your outboard calls for a Champion L77J4 plug be installed. Not sure what you have in there right now, but replace with Champion plugs ONLY. Once removed, and cleaned, definitely replace those carbs with NEW carb kits installed. No sense in doing it twice, and besides, they're cheap!! I'd see what came out of the decarb before removing the carbs, however. Get another can of the SeaFoam you mix with the fuel. Good stuff, as I'm sure you've already read the label and know this by now. No wonder they call it a mechanic in a bottle....... huh?.........I gave it a horrific test on an old sluggish 2 cycle kids fourwheeler that wouldn't even idle and stay running. Darn if it didn't do the trick!!! The thing runs better now than it ever has!! It will now sit and idle all day long. And I never turned the first screw on those carbs either. Good luck!!!....................ALAN

 

[ezeke]

Re: 1979 Evenrude 115 Outboard

I just checked the engine FAQ on this site to see what people get when they check it in regards to a decarb,

Squirting some Seafoam in the spark plug holes will hardly get it for you, ladies.

Whoever decided to change the text on how to decarb an engine has rendered an extreme disservice to the users of this site.

 

[Theoutdoorsman]

Re: 1979 Evenrude 115 Outboard

ezeke..... This is the link to the Decarb Process mentioned to gearyg earlier in the thread.......

http://www.iboats.com/bbboard/bbBoard.cgi?a=viewthread;fid=36;gtid=1035563

Are you implying that two senior members, Roscoe and Dhadley, are incorrect on their specific instructions, pertaining to the decarb process, to the rest of the community? What part of the process do you disagree with? If I'm not mistaken, gearyg asked how much to apply in each hole to allow overnight soaking. I simply stated a four to five second blast would, in my opinion, be an ample dose. If I'm incorrect, please explain for my future reference, and gearyg's interest as well.........Thanks.................. ALAN

 

[ezeke]

Re: 1979 Evenrude 115 Outboard

The comments by Dhadley are correct and appropriate to results, study and experience. They do not outline a decarb process.

Heretofore, the process was given more depth and also included a second method using a small tank which was very effective. The second process, which I believe is still found on the Boston Whaler site has been removed recently from this link. That is what I object to. I believe that I am as entitled to my opinion as you, sir.

The decision to make a forum public was not mine, but here it is.

If you want to learn more, here is a good link. Just copy it to your browser without the quotation marks. Their search engine works really well, too:

"http://continuouswave.com/cgi-bin/sw.pl?Search=decarb"

 

[ezeke]

Re: 1979 Evenrude 115 Outboard

Here is the link to the missing text by Captain Bob Dunkelberger, in case anybody wants it:

"http://outdoorsbest.zeroforum.com/zerothread?id=2589"

Copy to your browser without the quotation marks for best results.

 

[Theoutdoorsman]

Re: 1979 Evenrude 115 Outboard

"I believe that I am as entitled to my opinion as you, sir. "

ezeke....... If I offended you, please accept my sincere appology, as that was never my intention. Your knowlege in this field obviously surpasses mine, by far. Sharing information with others, to broaden our educations, is the beauty of a public forum. Your sharing of this information is greatly appreciated. Thank you. And once again.......no offense.....................ALAN

 

[ezeke]

Re: 1979 Evenrude 115 Outboard

No offense taken.

 

[Monahans]

Re: 1979 Evenrude 115 Outboard

G-Man,
If you need carb kits, the OEM ones are #439076 and they list for $29.95 each. You will need 2 kits. They contain all needed parts! And if you need a water pump, that number is 5001594 and lists for about 65 bucks. These forEverrudes last even longer with genuine parts!
Good luck

 

[Monahans]

Re: 1979 Evenrude 115 Outboard

sorry, but the carb kits are $29.95 each! Wish they werer .95 each!