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1993 JohnsonEvinrude 48 Special shift control box

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snake284

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"I am buying a used 16 foot bo

"I am buying a used 16 foot boat with a 1993 48 Special on it. The motor runs fine, but the guy selling it told me up front that the shift handle on the control box needs replacing. Is this a big deal, and is the part hard to find?}"
 
"Norman.... There are various

"Norman.... There are various control boxes with, of course, various control handles. None of them should be considered a big deal as far as locating one.

The question remains..... why does it need replscing, and what affect has the problem had on other portions of the control box."
 
"True, and that was another th

"True, and that was another thing I was wondering about. I didn't know just how to ask the question, so I figured I'd wait and dig into the box and see what it looked like. Mainly, here I was wanting to know if you could buy component parts such as the handle without buying the whole control box. The supposed reason it needs replacing is that the present owner told me that the handle was the problem for a stiff shifting, and grinding gears. You have to shift it fast, though it is stiff, or it grinds the gears(I hate that). This guy is known to be a straight shooter, and I would almost take him at his word. Of course, knowing this, you wonder why he didn't fix it himself if it is a simple problem. So that's why I'm here asking questions before I get off into bigger problems."
 
"Any part of any control box c

"Any part of any control box can be purchased right down to the smallest screw or the largest housing.

The grinding gear bit could spell expensive repairs to the lower unit though. Keep that in mind. The following may be of some help.

(Jumping Out Of Gear - Manual Type)
(J. Reeves)

This pertains to lower units on all OMC manual shift outboard engines, or any OMC engine with lower units defined as a Shift Assist or a Hydro Electric Shift unit which incorporates a "Shifter Clutch Dog".

Within the lower unit, splined to the prop shaft is what is most often referred to as a clutch dog, hereafter simply called dog. The dog has at least two lobes protruding from it on both ends, facing both forward and reverse gear. The forward and reverse gears also have lobes built into them near their center area. When the engine is running, in neutral, the gears are spinning constantly via the driveshaft being connected directly to the powerhead crankshaft, but the propeller does not turn due to the fact that the dog is centered between the two gears, and the dog lobes are not touching either of the gear lobes.

When the unit is put into either gear, shift linkages force the dog (and its lobes of course) to engage the lobes of the gear. The lobes of the spinning gear grab the lobes of the dog, and since the dog is splined to the prop shaft, the propeller turns.

The lobes of the dog and gears are precisely machined, most with right angled edges that could be installed in either direction, and some with angles slightly varied that must be installed in one direction only (one end only must face the propeller). Dogs that can be installed in one direction only, if reversed, even if the dog and both gears were new.... would jump out of gear almost immediately. Keep in mind that the lobes are precisely machined with sharp angles!

Due to improper adjustment or worn shift linkages, but usually due to improper slow shifting, those precisely machined sharp edges of the lobes become slightly rounded. Now, with those lobes rounded, as the rpms increase, the pressure of the gear lobes upon the dog lobes increases to a point whereas they are forced apart (jumping out of gear), and due (usually) to the shift cable keeping tension on the engines shift linkages..... the unit is forced back into gear giving one the sensation that the engine has hit something, and the cycle continues.

Some boaters have the mistaken belief that shifting slowly is taking ixt easy on all of the shifting components..... Wrong! Shifting slowly allows those precisely machined sharp edges of the dog and gears to click, clank, bang, slam against each other many times before they are finally forced into alignment with each other..... and this is what rounds those edges off! The proper way to shift is to snap the unit into gear as quickly as possible.

When time permits, visit my store at: http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
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