Will a 50hp powerhead fit a Johnson 55?

[steviecops]

Hi<br />I've got the chance to buy a rebuilt Evinrude powerhead for a very good price. It is just the bare block and head assembly with new crankshaft, pistons, etc. For the price, (about $150), I thought I'd buy it and stick it away just in case my engine lets go at some stage. Just one snag.<br /><br />It is a mid 80's Evinrude 50hp powerhead and my engine is a 1980 Johnson 55. Are these two powerheads interchangable? If so, would I have to re-jet my carbs if I fitted this powerhead, and would all the other bits like the throttle/ignition assembly fit?<br /><br />I'd appreciate any advice on whether to buy it or not.<br /><br />Thanks in advance<br />Steve

 

[steviecops]

Re: Will a 50hp powerhead fit a Johnson 55?

Can anyone offer any advice on this one?<br /><br />Thanks<br />Steve

 

[alcan]

Re: Will a 50hp powerhead fit a Johnson 55?

Stevie<br />With out model#s of both motors it is hard to say sitting here. My guess is NO they will not direct change. There are two familys of these twins in this era. The 40,48 and 50hp's. Then you have the 45 and 55hp. Now remember this is just a quick guess with quick reserch. I run a 1990 40hp myself. So I have studyed this some what. I am using 1988 parts manuals to make this call. I would like it for some one to prove me incorrect.

 

[jimmbo]

Re: Will a 50hp powerhead fit a Johnson 55?

No such thing as a 1980 55hp, in 1980 they had a 60hp. Oops they did make a 55hp, a commercial model, rope start with tiller handle.

 

[rodbolt]

Re: Will a 50hp powerhead fit a Johnson 55?

check the drive shaft splines. they changed in 88 or 89 and again in 93.<br /> good luck and if the splines work so will the rest.

 

[steviecops]

Re: Will a 50hp powerhead fit a Johnson 55?

Thanks rodbolt, I'd better check the splines. Having said that, this powerhead has a new crankshaft fitted, so the chances are, it won't fit. That's a shame (<br /><br />jimmbo, the model number of my engine is J55EL80C. What does that make it? Maybe a 1979 model that wasn't registered until 1980?<br /><br />Thanks<br />Steve

 

[jimmbo]

Re: Will a 50hp powerhead fit a Johnson 55?

As I said in my earlier post they did make a 55hp that year. It was a rope start model with a tiller arm with twist grip throttle. I guess it could get an electric starter added at the dealer and have remote controls fitted too.

 

[steviecops]

Re: Will a 50hp powerhead fit a Johnson 55?

Thanks jimmbo<br /><br />Assuming that mine is a commercial model, what is the difference, (if any), between the commercial and regular models apart from the rope start and tiller?<br /><br />Cheers<br />Steve

 

[steviecops]

Re: Will a 50hp powerhead fit a Johnson 55?

Hi<br />After not being sure about the crankshaft splines, I decided not to buy the powerhead. Then the seller told me to make him an offer as he wanted to get rid of it, which I did. I got the powerhead for about $silly in the end ;o)<br /><br />Now having seen it, I think it is a brand new powerhead. It is bare, unpainted aluminium which looks new, all the machined surfaces are still bright and shiny, and the bolt holes in the block that take various components don't look as if they've ever seen a bolt! All the bolts are new, the earth wire and temp sensor wire are also new, as are the cable retainers. Inside the crank case is spotless.<br /><br />The core plug on top of the block has a number and the OMC M stamped on it, but it isn't a model number. I'll try to post some pictures on here so someone might be able to tell me if this is a new powerhead.<br /><br />What I really need to know is, should this powerhead have grease in it? There seems to be some golden brown grease on the crankshaft bearings, and some around the gaskets where the head and exhaust cover fit. I know that needle bearing grease is called for during a rebuild, but I've never seen it, so I wouldn't know if that's what is in this motor.<br /><br />Should I try to get rid of the grease, or leave it where it is?<br /><br />Thanks<br />Steve