Evinrude 50 ('96) mis-behaving.

[fishmen111]

New member here folks. Very nice web site. I recently purchased a boat with a 1996 50 Rude with two problems that may or may not be related.. #1 cyl @ 90psi, #2 @ 145psi. Motor cranks right up, but there is a horendous clanking sound under/near the flywheel. After 5 minutes, clanking increases and engine dies. Restarts fine. I plan on pulling the head tomorrow to look for the commpression differential, but am not sure how far to tear down the rest. The motor cost me next to nothing, so I don't want to spend major bucks or time on it. However, with 145psi in one cylinder and looking like new, I also don't want to trash a possible cheap repair. Advise anyone? Thanks a bunch !

 

[tashasdaddy]

Re: Evinrude 50 ('96) mis-behaving.

your compression #s are way off. possibly a head gasket. but you need to pull the flywheel and see whats going on there. you need # 8 harden bolts to screw into flywheel (autoparts store). and a harmonic balancer puller.

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Thanks for the info. I will pull the head and flywheel tomorrow.

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Pulled the head, bores/pistons looked great. #1 piston top too clean. Head gasket is in bad shape. So I go to bolt her back up and start looking for the "clank" near the flywheel. I turn the flywheel several revolutions before putting the head on and something catches my eye. #1 has a small delay at the end of travel. I press on the piston on the down stroke and it moves a good 1/4". I can't believe it did not self destruct yesterday. On the bright side, I found my "clank" and may still be able to save it. It sure did sound external. Oh well, I will start the teardown tomorrow. I am sure I will have many questions later. Thanks for the help.

 

[tashasdaddy]

Re: Evinrude 50 ('96) mis-behaving.

get yourself an OEM manual, outboardbooks.com

 

[steelespike]

Re: Evinrude 50 ('96) mis-behaving.

Boy thats a bummer.I hope you didn't pay too much.

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Will get an OEM manual. Never done an outboard rebuild before. Should be fun. I really don't have too much to lose. I bought the boat last week and basically paid for the hull and trailer only knowing there were issues with the motor. If I find that the crank journal is trashed, I will probably strip it and buy a good used 50. They are everywhere here in eastern VA, and relatively cheap. Of course I will need to see the internal damage before deciding what to do. I am sure it will involve many annoying questions though (just kidding...I hope). Thanks again....Charles

 

[4.0l sahara]

Re: Evinrude 50 ('96) mis-behaving.

Get some pics when you take it appart.

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Will do!

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Finally got into the motor today. Oh well, got some good parts, glad I didn't pay much for it. Cylinder #1 rod had no bearings, just the remainder of the cage. Wonder where the needle bearings went? Exhaust? The rod is trashed and the crank journal is slightly scored. It measures in at 1.1819 which is 0.0004 under spec, but for the price of a rod and bearing and a little emory cloth work, I'm gonna put her back together unless they make oversize bearings for these motors...do they? Suggestions? Advise? I tried to load photos, but on my camera's lowest setting, they were still too large for the forum.

Thanks folks!

 

[rodbolt]

Re: Evinrude 50 ('96) mis-behaving.

no way can you polish it smooth and round and still keep it in spec, out of spec and it pukes rod bearings
there are some sites here that will sell good used cranks and rods.
never reuse a rodbolt nor a lower main.

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Thanks for your reply Rodbolt. So it is safe to assume that unlike typical four-strokes, you cannot turn this crank and use larger rod bearings? Bear with me, this is my first journey inside a two-stroke.

 

[reeldutch]

Re: Evinrude 50 ('96) mis-behaving.

there are no oversized bearings availeble.
you will unfortunatly need a new crank.
some people claim they can repair the crank i would be very sceptical about those claims.

 

[fishmen111]

Re: Evinrude 50 ('96) mis-behaving.

Thanks ReelDutch. I have done many "backyard rebuilds" over the years (drop the pan, mic the journals and put in 0.001 oversize bearings). I was just holding out hope for this motor. I will keep an eye out for a good used crank and piston/rod assembly. I have found a low hour '01 Johnson 50 for $1800 I plan on picking up this weekend. One curiosity question, when splitting the case, I was amazed to see no visable gasket. Is there some sort of clear liquid material they use? Thanks again!