Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves"

[flexon_guy]

I have a 35hp long shaft 76 Evinrude that is kicking out of forward gear at about one third throttle. It kicks out of reverse at about one half throttle. When I went to drop the lower unit to rebuild I noticed that the lower connecting rod bolt was different than the top and think that it may not be the original. I then noticed a small amount of play in this bolt allowing the lower shift rod movement before shifting into desired gear. I removed all the play and retightened this bolt and retried the lower unit which did not seem to change its kicking out of gear condition much. <br /><br />After removing the lower unit I noticed that the lower shift lever was turned out almost one full turn which would have caused this shift rod to be longer than if it was fully seated in the lower clutch yoke. It also seemed as though it may be bent. When twisted as beeing unscrewed from the yoke the top made a circle the circumfrance of a dime.<br /><br />My question is does it appear as though the lower shift rod is my problem? Would I be wasting my time to source a new lower shift rod and reinstalling the lower unit on the motor/boat to see if this works before procedding with a complete lower unit rebuild?.<br /><br />History of the motor is unknown and the gear oil was dark in color with green hues on a white background with no burt smell. If there was any metal shavings they went unnoticed in my cup.<br /><br />Thanks<br /><br />Mike

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Joe<br /><br />I am hoping that you can help me with this one.<br /><br />Thanks<br /><br />Mike

 

[G DANE]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

The jumping out of gear issue is often fixed by changing clutch dog, and sometimes forward gear. Other lower unit parts are tough and takes a lot of wear, as long as there is oil in it and no water. Start with inspecting gears and changing clutch dog alone. I dont think a slight sloppy connection, due to one different bolt in clamp will make it jump out of gear. For how long have you had this problem ??

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

G Dane<br /><br />Thnaks for the reply. The Motor was purchsed recently from someone that will not claim any problems. We ran it only half a dozen times trying to adjust it out. (No prior history) <br /><br />I was thinking that since the lower shift rod has to screw down into the yoke if this is out of adjustment maybe its not forcing it into forward gear enough. Thus kicking out. <br /><br />How much of a factor is a bent shift rod?<br /><br />Thnaks<br /><br />Mike

 

[G DANE]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

You can check the adjustment by looking at shifter arm at side of cowling. If it finds neutral pointing right up, adjustment should be OK. Change between F - N - R with motor lifted up from water. Rotate prop lightly by hand while changing, to avoid clutch dog binding. Listen to shift sound from lower unit. If it clicks into all gears, and you feel grip firm and good, its probably clutch dog problems. You can actually also feel if the adjustment gives the possibility to press it a little extra into gear, both forward and reverse.

 

[Solittle]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Some of the shift rods are bent by design. Also there is a height specification for the shift rod. The height is adjusted by screwing the shift rod in/out so don't just assume that it is out of whack. Chech the manual.

 

[Joe Reeves]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

The 1976 35hp shift rod simply screw all the way down into the yoke.... no measurement adjustment.<br /><br />(Jumping Out Of Gear - Manual Type)<br />(J. Reeves)<br /> <br />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".<br /> <br />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.<br /> <br />When the unit is put into either gear, shift linkages force the dog (and its lobes of course) to engage the lobes of the 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.<br /><br />The lobes of the dog and gears are percisely 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 percisely machined with sharp angles!<br /> <br />Due to improper adjustment or worn shift linkages, but usually due to improper slow shifting, those percisely 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.<br /> <br />Some boaters have the mistaken belief that shifting slowly is taking it easy on all of the shifting components..... Wrong! Shifting slowly allows those percisely 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.

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Joe<br /><br />Do you think that if the shift rod is improprerly adjusted it may not be forcing the gears all the way in - thus allowing them to kick out? Or do you think that the lobes are rounded. The shift rod was not completly seated into the yoke it was backed out almost one full turn. I cannot visualize what would happen if the shift rod was improperly adjusted about 1/4 inch long. <br /><br />I know if this condition was present for along time it would probably wear those gears but if you read my original post it is doing in both gears and more in forward than reverse. We do not have the history of the engine.<br /><br />Do you think I could get by with just a simple fix like a lower shift rod replacement and adjustment? Or do you think that this merits disassembly?<br /><br />Thanks<br /><br />Mike

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

G Dane<br /><br />Thanks<br />for your sugestions. I currently have the lower unit off of the motor. How do I check the clutch dog with the lower unit removed? It does shift into gears when I rotate the prop and pull up and push down on the shift lever.. What am I looking for?<br /><br />Thanks<br /><br />Mike

 

[G DANE]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Do you have a remote set-up or tiller handle ? The way the shift mechanism is constructed is rather forgiving. If rod is not screwed all the way in, shift lever will just not point right up at neutral. There is enough movement to shift farther than needed in both gears. The lower unit controls the movement. I think you are looking at a worn clutch dog, not that bad. If you have a remote comtrol box, box or cables can be faulty, then, but unlikely affecting both forward and reverse.

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

G Dane<br /><br />Controlled by shift box. When testing I was holding the shift lever with my hand trying to keep it in gear and it still kicked out.<br /><br />Thnaks<br /><br />Mike

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Do you think the forward and reverse gears are ok if this problem has not been going on for sometime? Since it kicks out in forward and reverse maybe just the worn clutch dog?<br /><br />Thnaks<br /><br />Mike

 

[G DANE]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Usually replacement of dog will do it. Jumping out of reverse is unusual, but happens especially if dog has been turned to solve same problem earlier. I would replace the spring behind the ball-lock too. If it pushes out of gear when you try to hold it in, its a sign of worn dog.

 

[flexon_guy]

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

Re: Tough lower unit question 35hp 1976 Evinrude - "Please help J. Reeves&q

G Dane<br /><br />I noticed that you recognized that it has the ball and springs. Do you have a recomendation on how to reasemble these balls and spring without the OMC sleave tool?