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1984 Merc 9.8 hp Shift Problem

2

2003hdflstc

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1984 Mercury 9.8 H.P. Serial # 6517870. Everything worked perfect, then had to replace impeller. After re-installation (multiple times) motor will not go into reverse and has no neutral. Motor will pull start in supposed neutral position however motor is actually in forward gear. While in this supposed neutral position and moving forwards, engine will only go slightly past idle speed. If I shift into actual forward gear, I can fly like the wind. If I try to shift into reverse, I get nothing, but there is no gear grinding either. Shift linkage feels fine and has expected movements when shifting gears from neutral to forward. Linkage does not feel like it is travelling far enough to engage into reverse. No part of the motor was taken apart other than the lower unit that comes apart with the two nuts and the impeller housing. Attempted to re-install with shift lever in neutral and in forward position with no difference.
 
They're a b*tch ain't they! (I hate working on these motors.)

As you suspected, the shifter is out of position relative to the LU. THe trick here is to take all of the slack out of th LU shaft before attempting to stuff her up there. Not sure which of the dopey shift patterns that year used, but you can see which way is forward by using the throttle: It won't open all the way in neural or reverse. With that determined (and I'd note it somewhere), put the top shifter in forward, the LU in forward (spin the prop to be sure), take the slack out, and try it yet again.

A couple of tips to make it easier:

Remove the O-ring at the top of the driveshaft, throw it away, and grease the splines instead. That makes life easier.

With the motor horizontal, look up the shifter shaft hole in the tower with a mini light. Is the female spline piece centered in the hole? If not, you'll MISS it when you stick th eparts together, resulting in NO shifting. I drill and tap the front edge of the tower for a 1/4 " screw to temporarily push the shifter shaft into position. (File the edge away, centerpunch, tap driill,then tap.) You can also try fishing a bent piece of wire in through the opening to shove that sucker into place.

Finally, study the splines on the shifter and you'll see that it only goes ONE way; there's a "blind spline" that doesn't allow it otherwise.

Jeff
 
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Another question, see attached photos. There appears to be a linkage adapter that I believe may be broken, however I cannot get to it. I have the Seloc and Clymer's manuals and neither one addresses what this part is or how to get to it. I do not want to start tearing the entire lower unit from the motor without knowing what I am getting into. This phenolic piece has a J slot in it and it appears it is there for a pin to ride in, but there is no pin to be found. The leading edge of this piece appears to be broken but I can't be sure. Any help identifying this part by name or number so I can order a new one would be helpful. At least then I can see what it is supposed to look like. Any help in where I can find a manual that details the dismantle and installation of this part of the lower unit would also help. Thank you in advance. Bob
2012-07-02 20.27.05.jpg2012-07-02 20.29.39.jpg2012-07-02 20.29.54.jpg
 
That would be for the reverse lock.------------If everything was in place it would lock the motor so it does not kick up in reverse.-----------Your motor will run fine without it.
 
That piece is hard to get to--the dynafloats have to be removed to expose it. You can check out if it's working by shifting it while looking up inside the tower with a mini light (and watching to so if the thin rod that locks the motor down in neutral and reverse moves).

Jeff
 
Hey,
I have a Mercury 9.8 hp outboard with a solid gear selector shaft just one piece that goes into the gearbox,I'm Having a hard time putting the lower unit back on. Can't tell what gear it's in because don't have anything to stick in gear box to change gears. have put up and then change gear. I tired everything,forward, and reverse, I thought I took the lower off in reverse and goes in but stuck in reverse? Do have have ideas? tricks I need to know
Thanks,
Tom
 
"I feel you pain!" (Sleazy Bill Clinton)

You can determine which way the LU shifter goes by turning the prop--it will click in one direction only (in forward) (and lock up both ways in reverse. Be sure the LU is in forward with all the slack taken out.

On the PH, the stock motor has a stop to prohibit full throttle in reverse--that's how you determine which way the shifter goes (and don't think that's "obvious", for some of these motors shift backasswards for some fool reason).

Next, stand the motor on its head, upside down--it's easier to do them upside down.

On the LU, if there's an o-ring at the TOP of the driveshaft toss it out--trust me on this. It's unnecessary and makes assembly difficulty. Just lube the splines thoroughly.

Next, if you have a grinder, grind a chamfer on the end of the shifter shaft (ie: point it so it can enter the parts easier). Make it 45 degrees and at least an 1/8 inch wide.

Next, try to slip the deal together, using the prop to turn the driveshaft so the driveshaft splines engage. DON'T force it. THe driveshaft will engage first, with the shifter engaging with about a 1/2 inch to go. Have an assistant wiggle the shifter if it won't engage.

Good luck!
Jeff
 
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tmf28 said:
Hey,
I have a Mercury 9.8 hp outboard with a solid gear selector shaft just one piece that goes into the gearbox,I'm Having a hard time putting the lower unit back on. Can't tell what gear it's in because don't have anything to stick in gear box to change gears. have put up and then change gear. I tired everything,forward, and reverse, I thought I took the lower off in reverse and goes in but stuck in reverse? Do have have ideas? tricks I need to know
Thanks,
Tom
Click to expand...


The only gear slector rod it has is a long one coming down from the linakege at the bottom cowl, that goes into the LU
 
when i pulled the LU off the gear selector rod stayed on the upper end? Was it soppose to stay in gear box? It was hard to take off
 
I hope there's a shift rod coming out o the lower unit as well! If not, you pulled it out when the LU came off. That means a rip down of the lU to get it back.

Common reason this happens is that the shifter connects in one position only--there's a 'blind spline'. When someone jambs it together in the wrong orientation it resists coming apart again and rips the shift shaft out of the LU.

I hate working on 'Slanters'.

Jeff
 
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