Loud "Clunk" When Shifting Into Gear

greg82255

greg82255

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Hello,

I have a 1986 Merc 260/Alpha One, just winterized it and am thinking about all the things I need to do to it in the off season. There is a loud "clunk" noise when I shift into both forward and reverse. It goes into gear and stays in gear without any other problems, and it happens every time I shift into either gear. I've been reading around and think it might be the lower shift cable, but all the bellows are in great shape and I don't want to pull anything apart if I don't have to. Is there a way to troubleshoot all the different parts that could be defective? And besides the cable, what could it be?
 
C

crazy charlie

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Re: Loud "Clunk" When Shifting Into Gear

Is your noise heard when the boat is in the water or are you on land on muffs?? Submerged in water will be much less of a clunk to hear.On muffs it will be a lot louder.Charlie
 
Don S

Don S

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Re: Loud "Clunk" When Shifting Into Gear

What's the engine idle rpm that you are shifting at? Do you have a SS prop?
 
S

sschefer

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Re: Loud "Clunk" When Shifting Into Gear

If you have a owners manual you'll find that it recommends a positive action when shift from neutral into gear. The dogs engage hard when they are in good condition and that clunk is usually a good sign not a bad one. Because of the way the dogs engage it is never recommended to slide it into gear since this causes excessive wear.
 
greg82255

greg82255

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Messages
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Re: Loud "Clunk" When Shifting Into Gear

crazy charlie said:
Is your noise heard when the boat is in the water or are you on land on muffs??
Click to expand...
I hear it on land and on the muffs. It's still very noticeable in the water.

Don S said:
What's the engine idle rpm that you are shifting at? Do you have a SS prop?
Click to expand...
The idle RPM is about 800-850 and I do have an SS prop.

sschefer said:
Because of the way the dogs engage it is never recommended to slide it into gear since this causes excessive wear.
Click to expand...
Agreed - I always push it right into gear, never slide it.
 
Don S

Don S

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Re: Loud "Clunk" When Shifting Into Gear

The idle RPM is about 800-850 and I do have an SS prop.
Click to expand...
No wonder it clunks loud. Way to fast of an idle speed, get it down to 650-700 like it's supposed to be, especially with a SS prop.
 
greg82255

greg82255

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Messages
781
Re: Loud "Clunk" When Shifting Into Gear

Alright, perfect. I'll set get it down to 650. So this means the lower shift cable is probably ok?
 
Bondo

Bondo

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Re: Loud "Clunk" When Shifting Into Gear

greg82255 said:
Alright, perfect. I'll set get it down to 650. So this means the lower shift cable is probably ok?
Click to expand...

Ayuh,... How old is it,..??
When shift cables wear inside, ya usually can't adjust it ti hit Both forward, 'n reverse...
If they get sticky, 'n drag, they cause stallin' when shiftin'...

The Clunk is kinds normal for an Alpha, but as noted, a High idle, 'n SSteel wheel are exacerbating yer's...
 
greg82255

greg82255

Senior Chief Petty Officer
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Messages
781
Re: Loud "Clunk" When Shifting Into Gear

It's a 1986 but I'm not sure how old the lower shift cable is. I bought the boat about 13 months ago and I was told it was always dealer serviced. I pulled the drive this year to check the gimbal bearing, u joints and bellows and everything looked good (except for maybe slightly worn u-joints that I mentioned in another thread), so I am lead to think that it was maintained properly. I have no problem hitting both forward and reverse, and it has never stalled when shifting - just clunks.
 
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