Drive shaft steel type

[FAV453]

What type of steel are the johnson drive shafts made out of? I don't think they are stainless. I wanted to get the one shaft I had that was stuck in the engine electropolished but that can only be done to stainless parts. How about other types of finishing that can be done to the shaft that would discourage corrosion?

 

[Paul Moir]

Re: Drive shaft steel type

I can't answer this for sure, but it is actually a stainless. I think Mercury was the only one who tried to get away with steel. The stuff I have is all martensitic (attracts a magnet) so I'm guessing it's something like 416. It does seem to machine very well.<br /><br />The crankshaft on the other hand is made of forged nickel-moly steel, so if any salt water gets between it and the driveshaft they will corrode together due to galvanic action. That's why it's so important to grease and seal the splines regularly.<br /><br />This was true in the 50s, 60s, and 70s anyway.

 

[DHPMARINE]

Re: Drive shaft steel type

I can't add much about compatability of steel parts,but I do know any splined fit needs some kind of protection,and if it wears off it needs to be replaced.<br /><br />Would a new waterpump and re-greasing the driveshaft splines every year or two work in this case ?<br /><br />What is electropolishing ?<br /><br />DHP

 

[FAV453]

Re: Drive shaft steel type

I still don't think the shaft is stainless given it does attract a magnet. Any others want to chime in? I did grease the shaft 2 years ago and one shaft stuck and the other one was fine in fact the grease was still in pristine condition. I know there is suposed to be an oring at the splines, but how could it ever work given there is no defined groove to hold it in place? And secondly how do you get the old one out when you change the shafts becasue niether of my shafts had a ring on it.

 

[lark2004]

Re: Drive shaft steel type

There are many types of stainless steel, some do attract magnets. The few types that you are thinking about that don't attract magnets (304 and 316 most likely) wouldn't be suitable for drivshafts as they work-harden very easily and would then break from the load that the engine puts on it.<br /><br />Read this, it will give you bit more understanding about the subject.<br /><br /> http://www.efunda.com/materials/alloys/stainless_steels/stainless.cfm

 

[Paul Moir]

Re: Drive shaft steel type

Stainless #416 is martensitic. <br /><br />Use a good quality "Marine" grease on the driveshaft splines as it won't wash away in time & has corrosion inhibitors in it. I don't know enough about your 225hp to say wheter or not it has an o-ring, the parts list seems to indicate not. Is it possible the driveshaft got stuck from something other than corrosion? Impact perhaps?

 

[R.Johnson]

Re: Drive shaft steel type

Probably the correct term would be rust resistant. If that shaft was truly stainless, machining it would be a real fun time. Marine grease, such as OMC triple guard should be all you need with normal maintainence. Are the spline's on the shaft distorted from impact damage?

 

[FAV453]

Re: Drive shaft steel type

The splines are not damaged at all. Like I said a little rust was evident. I don't think an oring goes on this model.