1973 50 hp evinrude (50373r) bogs down past half throttle

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
When I get home this evening I will do what you suggest and push down on the pistons and work on resurfacing the head some more.

In for a penny, in for a pound is right. I have gone through and repaired so much that it seems stupid to quit now. As far as money I started out dropping 1500 bucks on this old boat because everything else in the price range was a Jon boat. Now I see why the good deal.lol. I have about 500 in so far and if I can get this thing right for less than another 500 I feel like I will still be doing well on the overall purchase. Plus I am learning quite a bit through all of this, both about outboards and purchases. If I have to tear this thing down then so be it, I am just ready to fish is all. If I do end up rebuilding this thing I least I will know the condition of it through and through and I will have a reliable motor out there on the water.

I will post something when I get home and check the rod bearings the way you suggested. Thanks again fellas.
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
So with the piston on the down stroke ever so slowly I stopped. Push down on pistons while holding the flywheel still. It takes about the same amount of pressure and distance to feel it and heat it "click" on both pistons.
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
No Title

I'm afraid to keep going far enough to remove the color between cylinders. Should I keep going?
 

Attachments

  • photo241375.jpg
    photo241375.jpg
    87.6 KB · Views: 0

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,612
more, imo..... Like to use a sheet of 400 wet/dry on my old table saw top, wetting both sides of the paper. Figure eight pattern.
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
Gonna keep going then. Using 400 grit emery taped to a sheet of glass on my coffee table. Man this is gonna take a while
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
39,352
Post # 83 tells me that with a new headgasket you are good to go !
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
I sure hope so. Gotta go get some more emery cloth. Then more sanding! I went ahead and bought the fuel pump rebuild kit and all new fuel lines under motor cover too. Cheap and easy enough. I bought permatex gasket sealer #1 for water jacket cover, hopefully that's the right stuff. How long after assembly do I need to wait to run it
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
No Title

Well that's good. I was worried about waiting on gasket sealant since I plan to put a light coating on both sides of water jacket cover gasket. Time to get back at it
 

Attachments

  • photo241379.jpg
    photo241379.jpg
    88.9 KB · Views: 0

AlTn

Commander
Joined
Mar 9, 2010
Messages
2,813
I believe the permatex no.3 aviation gasket sealant would be a better choice in this application
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
Well that figures. I bought 1 and 2. Napa didn't have 3. Napa is right next to my daughters daycare, is there anything I can get there when I go get her. I hate to put this together wrong. Otherwise I have to wait till Monday since the marine store is an hour away and will be closed by the time I get there
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
No Title

Should I keep going? Feels smooth and I cannot see striations anymore
 

Attachments

  • photo241395.jpg
    photo241395.jpg
    91.6 KB · Views: 0
  • photo241396.jpg
    photo241396.jpg
    87.8 KB · Views: 0

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,612
see improvement from the last pic (center, around the cylinders) -- think you probably have it. Sooo...maybe give it just a tad more.

When using Permatex, I use no.2 if that helps (2B) -- has worked well.
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
No Title

Okay, one last round on the table. I thought 1 because it says resistant to water and 2 said oil gas and grease
 

Attachments

  • photo241397.jpg
    photo241397.jpg
    82.7 KB · Views: 0

AlTn

Commander
Joined
Mar 9, 2010
Messages
2,813
water cover leak isn't going to be an engine destroyer..use what suits ya...No.1 dries hard which may make it more difficult to get back off at some point...No.3 is the equivalent of OMC Gasket Sealant and is a non hardening formulation...I doubt No.1 or 2 will ever cause an issue for a water cover
 
Last edited:

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
So I went ahead and torqued the cover on with some #2. Seemed closest to #3. Seemed easier to do on the table than after mounted on the block. It has been sitting about 2 hours so now that the kids have had lunch I'm going to put the head back on. I'm going to pull the foot after that and inspect the seal, probably use some more #2 on that. Easiest way to get the the linkage bolt under bottom carb is pull the carbs I would assume. I never used any sealer on intake gasket, should I remove it and apply some there too?
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
39,352
No , you remove the starter to find the shift rod screw in plain view.----No need to remove a carburetor !
 

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
Well I'm glad I asked. Thanks for the heads up
 
Last edited:

jake83

Seaman
Joined
Mar 12, 2016
Messages
74
Well sweet. Looks like I can see the finish line. We will just have to see if I can cross it in my boat. Lol. I really appreciate all the help.
 
Top