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1982 Mercury 9.8 reverse problems

M

mrcorrao

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I removed the foot off a 9.8 merc to install an impeller. When I assembled I had forward and neutral - but no reverse. Every thread I read said I must have installed wrong. So tried a few more times with same results. So now I have the foot off and still not getting the "throw" I need from the shift lever. I will try to attached some pictures. IN: Forward the selector clicked into a detent under the cowl. Neutral also clicks into a detent. Reverse does not move enough to hit the detent (Lower unit is removed from engine)

My thoughts are that maybe this engine has some sort of safety that will not allow reverse if it is not locked to the transom? does this motor have anything like that? Also the manual says the engine can be damaged it shifted into reverse when not running... but what will get damaged/ what should I look for?

Thanks for any help.
 

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Did it shift properly before you did the impeller ,yes or no ?------Motor should not be shifted to reverse when not running.----Shifting between forward and neutral is OK.----Prop must be turned when shifting to reverse on a stand.-----Look at the reverse lock mechanism as there may be issues there.
 
Thank you - I never tried before. new purchase - I started the engine in a bucket and did not get any water. So I shut down and replaced the impeller.

Can you give me some details on the reverse lock mechanism – how should it function?
 
How did the water pump impeller look? This motor has a locking mechanism that keeps the motor from kicking up when in reverse, then releases it to tilt up in neutral and forward. Check to make sure that nothing is obstructing that movement down by the transom bracket and trim adjustment pin. Could also be that there was a pre existing condition that you didn't know about. I work on lots of these and have several in my shop right now, so let me know if you need some photos, or even need parts. The rotation of the shifting shaft, of course, activates this lock mechanism. Parts are made of plastic here and if carelessly operated.....damage occurs.
 
The impeller only had 3 blades left - and they were in rough shape. I blew out all the junk and got a good strong stream from the engine.

Just to be clear the damage of shifting into reverse is to the lower unit? So with the lower unit removed I should be safe to investigate and mess with the reverse lock and shift into reverse on the stand? Thanks for your help.
 
Right. If it shifts good with lower unit off then you are off one tooth on the splines and lock is not causing the trouble. I could tell another way, but if you do it your way, you will have the answer too.
 
Those are very difficult motors to put the leg back up. After you get the water pump working correctly (and I recommend a bucket test to make sure) you can have an easier time of it if you follow the following procedure:

Turn the rest of the motor upside down.
Look where the shifter goes and see if the fe,ale portion coming down is centered. If not, use paper towels stuffed in there to force it centered.
Put the shifters both in forward.
Take all the slack out of the LU side and slip it together.
With the prop in place, turn it to get the driveshaft to engage the crankshaft.

Jeff

PS: If there's an o-ring at the top of the driveshaft, throw it out and lube the splines thoroughly. Much easier to get the thing together.

PSS: THe photo below shows how to spin the driveshaft with a drill to test the new impeller.
 
Don't throw the o-ring out.-----On some of these the hole for the spine goes right into the crankcase.-----O-ring is needed to seal crankcase compression !!
 
Ok – was able to investigate a little more tonight. 99% sure the problem is with the reverse lock cam. F/N/R do not give any vertical movement to the rod leading to the transom hooks. Just a slight side to side binding. When I shift to Forward I have to manually move the rod to release the engine and tilt. Can't see any obvious damage, but it might just be wore out. When I shift to Reverse, the cam rotates and seems to bind up and not allow full motion of the shift lever.

So... Can I bypass this and not have a reverse lock? Or what would be involved replacing?
 
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You really need to keep that lock, especially if you backtroll while fishing. Determine which parts are bad and notify me, I will direct you to cheap used or you can just order new from this site.....marineengine parts. I have seen a lock release done with a wire or makeshift string/cord, but it will take a little creativity on your part. Make sure to have it in release mode when traveling in high speed forward....in case of rock strike or grounding. Maybe you don't care about backing up, but that lock is a must for fishing using a backtroll method.
 
The more I look at it - It appears to me that if it was removed and turned one spline over it would work correctly. When I place the engine in forward it rotates and I still have about of 1/2" of travel for the metal rod remaining. When I shift to reverse it bottoms out in the groove to soon. So I would think I need to center the piece to allow equal motion in each direction.

Do I need to remove the saddle to access this? From what i see it is 4 Snap rings to release the pins and I should be able to gain access. Is this correct?
 
..."On some of these the hole for the spine goes right into the crankcase"

Not on this motor.

There's an orphan spline in that shifter coupler that is supposed to prohibit the shifter coupling from going together all but one way. Unfortunately, most of the (female end) of the couplers were plastic, which allows one to force the coupling together improperly. When that happens, you not only don't achieve reverse, separating the gearbox often rips out the lower shift rod.

Jeff
 
Can someone recommend a manual that covers changing the Reverse lock cam or give a few pointers?
Its not covered in the book I looked through
Thanks
 
I recommend you install the o-ring on the driveshaft.----On some the crankshaft hole for the spline goes right into the crankcase !!
 
..."I recommend you install the o-ring on the driveshaft.----On some the crankshaft hole for the spline goes right into the crankcase !! "

Not on this motor!

Jeff
 
How would one know what crankshaft is installed in a 35 year old motor ?-----Perhaps it is not original and therefore I recommend installing the o-ring.-----I have never had a problem installing those lower units.----Nothing to it at all.
 
Guys - I have not had a problem installing the lower unit - And I have the ring in place.
My problem is the shifter will not shift into reverse even when the lower unit is removed. It is binding - that is why I requested info on the reverse cam
 
..."How would one know what crankshaft is installed in a 35 year old motor?"

You won't let that drop, will you? (No O-ring is needed and makes reassembly difficult.)

Which way are you turning the LU shifter? Also which way does the top half of the shifter turn as you go from F to R? (There was two versions of that shifting setup.)

Jeff
 
Personally I install that o ring to help keep grease or anti seize in place.....and help keep moisture out......but that's just me, my 50 years in marine repair has taught me to not only follow good advice, but stand behind what you do.....that's how I have learned. You 2 guys are among our top 5 techs, this o ring is not a big deal.
 
When you are desperately trying to get the LU to go up there that last inch or so, the O-ring fights you.

I've restored about 3 dozen of these and know what I'm talking about.

Jeff
 
look at the locking assembly between the transom brackets. That lock needs to hold the motor down in neutral and reverse. It should only release the motor in forward.
 
I often set the lock to release in neutral too....that's just me.....doing what I shouldn't do, but what works better for my guiding. That way it is already in neutral when I tilt down the motor and start it. I have maybe 15 of these little Mercs around, and as I sell them, most customers appreciate the modification.
This preference possibly leads back to the "manual" locking systems used over the years with Johnson / Evinrude, which were more commonly used at our Ontario camps where I grew up.
 
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