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1986 Johnson 70 [Lower Unit loud clicking]

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Preacher76

New member
I bought a lower unit on EBay. I set the shift rod height to factory spec 21-29/32 (one of the many conflicting factory specs I found online). It lined up with the controls almost perfectly. It shifts into forward and reverse effortlessly. When on a hose there is no noise, but when under ANY load there is a loud clicking/popping sound.
With the engine off I turned the prop in forward and reverse drive and every 1 revolution in forward or in reverse the unit makes a loud popping sound and the prop seems to slip about an inch.
Is this an issue of further adjustment, or a bad gearcase?
THANKS for any help you can offer.
PreacherMan
 
Bad lower unit. There is a part in there called the clutch dog. It meshes with both the fwd and the Rev gears, depending on which gear you are in.
Sounds like the dog and gears are worn out.
 
Thanks for your advice. My suspicion was that the clutch dawg wasn't engaging properly but I was hoping beyond hope that it was a simple installation error that I could remedy.
 
When it is doing that, you will find excessive metal in the LU oil.
Also, the fix requires you to purchase both FWD and REV gears, as well as a new clutch dog.
Then there is the installation.....

If you tear into it, look at clutch dog "teeth" and note the rounded edges. They should be square. The mesh location on both FWD and REV gears will be rounded too.

And, by the way, it is caused by "lingering through the shift" (or can be).
DO NOT linger through the shift. Shift it fast and purposefully, do not allow it to "ratchet" or grind as it tries to engage gear.
 
Thank you for your responses! I'm headed to a professional for the rebuild. I think that job exceeds my abilities.
daselbee said:
When it is doing that, you will find excessive metal in the LU oil.
Also, the fix requires you to purchase both FWD and REV gears, as well as a new clutch dog.
Then there is the installation.....

If you tear into it, look at clutch dog "teeth" and note the rounded edges. They should be square. The mesh location on both FWD and REV gears will be rounded too.

And, by the way, it is caused by "lingering through the shift" (or can be).
DO NOT linger through the shift. Shift it fast and purposefully, do not allow it to "ratchet" or grind as it tries to engage gear.
Click to expand...
 
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