Johnson 55EL77D exhaust leak at powerhead

[Watermann]

Decided that the black oily carbon that started running down the fresh paint on my 55 Johnny last season needs to be stopped up. It runs out from under the exhaust housing cover and is clearly exhaust residue and not fresh oil/gas from the carbs. This leads me to believe that the leak is at the power head.

Looking at the breakdown of the exhaust system the only gasket I can see is part # 0351019 adapter to housing gasket but since I haven't ever gone this far in before I'm not sure and looking for some confirmation on what gaskets I would need for the repair.

Here's what I'm seeing. Thanks for any input guys!

 

[boobie]

The gasket I found was 321510.

 

[tommarvin]

Take the cover off and run it on muffs, and make sure its an exhaust leak. I don't know if this could be a head gasket. You never know .

Be prepared if you snap off a bolt,to remove it,drill it out, tap, put in heli coil. Get a inch pound torque wrench at HF, and all other tools you need.

Sweet 55 johnny, You could tear it down to the gasket, and see if the new gasket has the same number of holes, and same shape.

Check back, this forum will help you fix your boat period.

 

[Watermann]

The gasket I found was 321510.

Thanks boobie, I saw that one too but thought it was upstream from the one I listed. Got it added to the parts list, always nice to have a second set of eyes.

Take the cover off and run it on muffs, and make sure its an exhaust leak. I don't know if this could be a head gasket. You never know .

Be prepared if you snap off a bolt,to remove it,drill it out, tap, put in heli coil. Get a inch pound torque wrench at HF, and all other tools you need.

Sweet 55 johnny, You could tear it down to the gasket, and see if the new gasket has the same number of holes, and same shape.

Check back, this forum will help you fix your boat period.

True that Tom

 

[oldboat1]

Hi Waterman. Great restoration there!

Doesn't the exhaust housing cover attach to the housing with four or five screws somewhere down in the lower motor cover? The gasket you mentioned (351019) might partly fit between the exhaust housing cover and the housing(?) -- think you might be able to stop a minor leak by simply resetting the screws, maybe with a little OMC gasket sealer or similar. Maybe not.

 

[Watermann]

Thank you much oldboat!

Yeah I'm not sure what I'm going to need exactly until I get into it but I'm going to try and have all the gaskets I think I'll need. I'm not sure about the OMC sealer on the power head exhaust gasket, not been in there yet to even know what everything looks like or if the gasket is regular material or heat resistant.

Was hoping maybe someone would come along that has done the job on this or a similar motor and have some words of wisdom or know for sure what gaskets are needed.

I'll take the extra eyes on the parts breakdown though, thanks.

 

[Chrisravosa36]

I Am currently working on a 74' Johnson 50hp, your leak could be from the powerhead to the exhaust housing, or from the midsection to the exhaust housing, I had to replace both gaskets.

Those numbers are for my motor, but gives you an idea.
[h=1]0315852 GASKET, Adapter to powerhead[/h] [h=1]0315861 GASKET, Adapter to housing 1[/h]

 

[Watermann]

Thanks Chris, those are the 2 gaskets I'm thinking I need for my 55. :thumb:

 

[oldboat1]

Hmm, gaskets should be the easy part of the job:

1977 Johnson 55 hp 55EL77D:
OEM Part 0351018 - Powerhead Adaptor Gasket
OEM Part 0351019 - Gasket, Adaptor to Housing

Good luck with the project. Nice motor.

 

[tommarvin]

Free factory outboard service manuals at www boatinfo.no/lib/library.html.
Run it on muff first to make sure you find the leak the first time.

 

[Chrisravosa36]

Take off that middle plate, run it a bit and see if you can figure out which part its coming from, could be upper or lower gasket. Your going to need to do this anyways to get to the gasket.

 

[Watermann]

Thanks for taking the time to stop by. I should be good with both gaskets I ordered for the exhaust adapter and power head. Luckily if I run into the need for more parts, the parts place I order from is in the same State so I get my order in 2 days. Tossed in a new impeller on the order too for good measure.

I just hope that the bolts all come out without trouble, I doubt they've been out since 1977.

 

[Watermann]

Got all of the bolts pulled out without a problem and have the old smoker torn down. Thankfully the leaking gasket is the lowest one that goes between the exhaust housing leg and the powerhead so I don't see the need to go any further since the upper gasket isn't even discolored. Hoping I can find the torque values on everything in my almost worthless Seloc manual.

On the downside when looking closely I can see the side exhaust cover is going to need replaced one of these days but for now it's just weeping a slight film of 2 stroke oil onto the white paint.

 

[Watermann]

Just to add info to our library when doing this job and removing the water pipe, be sure to order the washer that seals the pipe at the upper end. Also this era of Johnson/Evinrude the rubber grommet has been replaced by a hard plastic washer. I thought that it was the wrong part atfirst but it wasn't and water flows just fine.