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Honda BF20 grinding/clicking gears in neutral

T

Towens17

New member
My recently purchased 2017 BF20 4 stroke has an issue with grinding gears when in neutral. When the motor is in neutral, it grinds (clicks) and seems like it wants to engage reverse. To avoid the grinding, I can pull the gear shift lever slightly forward(not engaging forward gear) to release pressure and the grinding will stop. Shifting into forward works just fine, same with reverse. Just when it is in neutral it seems like it’s in between gears and wants to grab reverse. I tried adjusting the linkage up and down but that didn’t seem to help much, if at all. I just did a gear oil change, no water in the oil. Any advice is appreciated!
 
Hi,
Is this a tiller model or remote control?
When you say that you adjusted the linkage, do you mean:

under the hood?

at the shifter console (remote with cables)?

or at the shift rod/shaft that sticks up out of the front of the gearcase?

Reference items 11, 30 and 12 in the link below for the shift rods and adjustment nut:

Honda Outboard 20HP OEM Parts Diagram for WATER PUMP + VERTICAL SHAFT (S,L) | Boats.net

Buy OEM Parts for Honda Outboard 20HP WATER PUMP + VERTICAL SHAFT (S,L) Diagram
www.boats.net www.boats.net

My first thought was that the shift rod just needed a minor adjustment. That's the first thing that should be checked in a case like this. Oftentimes the jam nut holding the longer adjustment nut comes loose and the adjustment gets out of whack. Sometimes it's just that the shift rod wasn't properly adjusted in the beginning and it has just "drifted" that tiny bit more to cause this issue.

If you adjusted anything other than the shift rod, you may need to go back on that to get back to a place that a shift rod adjustment will be effective.

With the other shift components back to their former settings, the shift rod can be adjusted.
Sometimes it's best just do a "base" adjustment.

....NOTE: Anytime you shift ANY outboard that isn't running (dry shifting) rotate the prop slowly at the same time. It doesn't matter in which direction. It just needs to be slowly turning to prevent the clutch from hanging up so that you don't accidentally bend the upper or lower shift rods.....

Shift the outboard into reverse to fully expose the adjuster and jam nuts on the forward exterior portions of the cases.

Loosen the jam/locking nut while holding the long adjustment nut (item 11). You will need two 10mm open end wrenches.

Turn the long adjustment nut clockwise so that it climbs UP the upper shift rod (item 13 in the link above) and disengages the lower shift rod.
Rethread the adjustment nut onto the lower shift rod slightly then turn it so that it travels down the threads for 3/16".

That will USUALLY give a good adjustment but is considered preliminary until you test it. Tighten the jam jut keeping in mind you may need to loosen it again if necessary.

You will then need to either run the outboard in a tank or trashcan with water (I don't recommend muffs for this) to ensure that you do have a good adjustment with proper gear engagement. Try it several times at idle. Neutral to forward- pause-back to neutral-pause-neutral to reverse-pause- reverse to neutral. Once you are satisfied with the adjustment, tighten the jam nut securely. Don't "muscle" it down but do keep in mind you never want it to accidentally loosen on it's own.

I'll tell you something many boat operators don't know but should.
Outboards have "dog" clutches. Because of the way dog clutches engage, it's important that shifting only be done at idle and gear selection should be made with a swift, firm motion to keep the clutch "ears" from bouncing off of each other while rotating.
A slow, "lazy" gear engagement will often result in a chattering noise from the gear housing. That chatter is the sound of the dog clutch being slowly ruined.
Just sayin'.

If this adjustment doesn't straighten out this problem for you then the next place you will want to look might be behind the propeller. You WANT to periodically look there anyway because it's important to do so.

There is a thrust washer behind the prop and it can be a high wear item. I personally consider thrust washers as "consumable" items that often need replacing. A badly worn thrust washer is bad for the gear housing and might even set up a "prop pulse" situation during low speed, low power operation because of the excessive clearance it allows.

Bent blades, or a worn, damaged hub could also cause noises from the lower end.

Also you want to take a peek in there because things (like fishing line) tend to wrap around the shaft and that can cause damage you don't need like a leaking prop shaft seal.

Hope you figure it out.

Please let us know what you find.
 
jgmo said:
Hi,
Is this a tiller model or remote control?
When you say that you adjusted the linkage, do you mean:

under the hood?

at the shifter console (remote with cables)?

or at the shift rod/shaft that sticks up out of the front of the gearcase?

Reference items 11, 30 and 12 in the link below for the shift rods and adjustment nut:

Honda Outboard 20HP OEM Parts Diagram for WATER PUMP + VERTICAL SHAFT (S,L) | Boats.net

Buy OEM Parts for Honda Outboard 20HP WATER PUMP + VERTICAL SHAFT (S,L) Diagram
www.boats.net www.boats.net

My first thought was that the shift rod just needed a minor adjustment. That's the first thing that should be checked in a case like this. Oftentimes the jam nut holding the longer adjustment nut comes loose and the adjustment gets out of whack. Sometimes it's just that the shift rod wasn't properly adjusted in the beginning and it has just "drifted" that tiny bit more to cause this issue.

If you adjusted anything other than the shift rod, you may need to go back on that to get back to a place that a shift rod adjustment will be effective.

With the other shift components back to their former settings, the shift rod can be adjusted.
Sometimes it's best just do a "base" adjustment.

....NOTE: Anytime you shift ANY outboard that isn't running (dry shifting) rotate the prop slowly at the same time. It doesn't matter in which direction. It just needs to be slowly turning to prevent the clutch from hanging up so that you don't accidentally bend the upper or lower shift rods.....

Shift the outboard into reverse to fully expose the adjuster and jam nuts on the forward exterior portions of the cases.

Loosen the jam/locking nut while holding the long adjustment nut (item 11). You will need two 10mm open end wrenches.

Turn the long adjustment nut clockwise so that it climbs UP the upper shift rod (item 13 in the link above) and disengages the lower shift rod.
Rethread the adjustment nut onto the lower shift rod slightly then turn it so that it travels down the threads for 3/16".

That will USUALLY give a good adjustment but is considered preliminary until you test it. Tighten the jam jut keeping in mind you may need to loosen it again if necessary.

You will then need to either run the outboard in a tank or trashcan with water (I don't recommend muffs for this) to ensure that you do have a good adjustment with proper gear engagement. Try it several times at idle. Neutral to forward- pause-back to neutral-pause-neutral to reverse-pause- reverse to neutral. Once you are satisfied with the adjustment, tighten the jam nut securely. Don't "muscle" it down but do keep in mind you never want it to accidentally loosen on it's own.

I'll tell you something many boat operators don't know but should.
Outboards have "dog" clutches. Because of the way dog clutches engage, it's important that shifting only be done at idle and gear selection should be made with a swift, firm motion to keep the clutch "ears" from bouncing off of each other while rotating.
A slow, "lazy" gear engagement will often result in a chattering noise from the gear housing. That chatter is the sound of the dog clutch being slowly ruined.
Just sayin'.

If this adjustment doesn't straighten out this problem for you then the next place you will want to look might be behind the propeller. You WANT to periodically look there anyway because it's important to do so.

There is a thrust washer behind the prop and it can be a high wear item. I personally consider thrust washers as "consumable" items that often need replacing. A badly worn thrust washer is bad for the gear housing and might even set up a "prop pulse" situation during low speed, low power operation because of the excessive clearance it allows.

Bent blades, or a worn, damaged hub could also cause noises from the lower end.

Also you want to take a peek in there because things (like fishing line) tend to wrap around the shaft and that can cause damage you don't need like a leaking prop shaft seal.

Hope you figure it out.

Please let us know what you find.
Click to expand...
I appreciate the in-depth response! This is a tiller motor with the exposed shifter rod linkage on the arm. Your explanation makes sense and I think I just didn’t spend enough time working with the linkage to fully come to a conclusion. Also didn’t help that I did not have two 10mm open ended wrenches.
You said shift into reverse to do this, the linkage nuts are exposed while I’m in neutral, could this be an indication that the linkage is off? Should I be able to access those nuts while in neutral? Also, when the motor is off, it doesn’t really let me shift into reverse, any tricks to get past that other than starting the motor?
Thanks again for you help.
 
Well, I haven't worked on any newer than 2010 but I don't think any of them have a reverse lock out mechanism so not being able to obtain reverse might be because you're not turning the prop while trying to shift by hand.

As far as can you access the adjustment nuts in neutral, yes I think you can...barely.... but it's so much easier in reverse.
And, the 3/16" adjustment might not work properly if it's not done in reverse. I don't know because I've never tried it that way.

If you rotate the prop and it still won't go into reverse, then there may very well be a problem either with the linkage or internal to the transmission.

Are you sure your "linkage adjustments" didn't introduce a problem with the linkage?

You could check that by disconnecting the lower shift rod from the upper and then turn the prop while pushing DOWN on the lower rod. It should go into reverse that way.
You might need to use a pair of pliers to grip the rod to push it down. I always used a small pair of vice grips when doing that but pliers will work.

If it goes into reverse that way then you can then see how the upper linkage works by simply shifting to reverse with the handle as you normally would. It should move easily and the lower end of the upper rod should then be very near the upper end of the lower rod.

Let us know what you find.

Good luck.
 
jgmo said:
Well, I haven't worked on any newer than 2010 but I don't think any of them have a reverse lock out mechanism so not being able to obtain reverse might be because you're not turning the prop while trying to shift by hand.

As far as can you access the adjustment nuts in neutral, yes I think you can...barely.... but it's so much easier in reverse.
And, the 3/16" adjustment might not work properly if it's not done in reverse. I don't know because I've never tried it that way.

If you rotate the prop and it still won't go into reverse, then there may very well be a problem either with the linkage or internal to the transmission.

Are you sure your "linkage adjustments" didn't introduce a problem with the linkage?

You could check that by disconnecting the lower shift rod from the upper and then turn the prop while pushing DOWN on the lower rod. It should go into reverse that way.
You might need to use a pair of pliers to grip the rod to push it down. I always used a small pair of vice grips when doing that but pliers will work.

If it goes into reverse that way then you can then see how the upper linkage works by simply shifting to reverse with the handle as you normally would. It should move easily and the lower end of the upper rod should then be very near the upper end of the lower rod.

Let us know what you find.

Good luck.
Click to expand...
I was able to get everything squared away. I think my issue was trying to adjust the linkage in neutral. Once I made the adjustment in reverse, everything worked as it should. Thanks again for the help.
 
Good news!

Glad you got her fixed up!

I didn't know if trying to make that adjustment in neutral would work or not but now I know it won't.

Thanks for taking the time to post the update and explanation about what you had to do.

Happy boating!
 
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