Clunk when engaging forward and reverse

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Aug 19, 2005
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'99 Bayliner 1950 CL 3.0L/Alpha1-genII drive. There has always been a small clunk when ehgaging the drive, but last time out it was more pronounced. Idle doesn't seem high and I recently changed gear oil and replaced the gimble bearing - ujoints looked and felt smooth. Any help for this newbie would be appreciated.<br />Thanks<br />Matt
 

Don S

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Re: Clunk when engaging forward and reverse

Idle may not "Seem" high, but if it's over 750rpm, then that is your problem. The engine should idle between 650 and 700 rpm.
 

WillyBWright

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Re: Clunk when engaging forward and reverse

Is your propnut tight? A lot of people put those on fairly loose. It should be tight.
 
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Re: Clunk when engaging forward and reverse

Thanks Don and Willy-<br /><br />I can't say I know what it is idling but I do know after the gimble bearing was replaced the drive really freed up. Could the rough gimble been holding the idle down prior to the change, and now be running higher?<br /><br />I have never had the prop off, but am courious how that might effect the noise im hearing. seams to be the noise of the gears engaging hard.<br />What effect would the prop have?<br /><br />Thanks<br />Matt<br /><br /><br />Thanks<br />Matt
 

rodbolt

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Re: Clunk when engaging forward and reverse

the gears never engage or disengage, just a mechaical slam shift clutch. it should give a clunk not a chatter when shifed. if you detest the clunk next time go with volvo :) :)
 
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Re: Clunk when engaging forward and reverse

rodbolt-<br />Don't neccisarily detest, just noticed a difference from my last time out. Being a marine tech can you shed any light on my previous post? All new to me - How is the volvo different?<br /><br />Thanks<br />Matt
 

Don S

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Re: Clunk when engaging forward and reverse

The Volvo drives do not have the dog type clutch in the lower units like the OMC and Mercruiser Alpha drives do. They have a cone clutch that slips quietly into either the forward or reverse gear and disengages just as easily as it engages.<br />This also eliminates all the shift interrupt switches and extra cables and associated equipemnent needed to make the OMC and Merc Alphas come out of gear.<br />The raw water pumps are located on the engine in Volvos, no more pulling the drive apart to replace the impeller every couple of years.
 

Richard Petersen

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Re: Clunk when engaging forward and reverse

Don. Is there a, or several reasons why the Alpha drive water pump can not be bypassed by a raw water pump and filter on the main engine?
 

Don S

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Re: Clunk when engaging forward and reverse

cyclops2, that would be a perfect question for a new thread, instead of hijacking Matt's thread about clunking gears.
 
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Re: Clunk when engaging forward and reverse

Right on as usuall Don. RPMs are running 850-900 at forward idle.<br /><br />Thanks<br />Matt
 

baja power

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Re: Clunk when engaging forward and reverse

Bravo drives Don't clunk into gear, Nor do TRS or Speedmaster drives...
 

Don S

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Re: Clunk when engaging forward and reverse

Bravo drives Don't clunk into gear, Nor do TRS or Speedmaster drives...<br />
So, Baja, what does that have to do with AZMatt's post? He has neither, he has an Alpha drive.<br />Are you suggesting he change engines and drives to get an old TRS or Speedmaster so it won't clunk if the rpm is too high? Or maybe repower with a bigger engine so he can get a Bravo?<br />Even with those systems, to high an idle, and they will clunk...... Trust me.
 

baja power

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Re: Clunk when engaging forward and reverse

Originally posted by Don S:<br />
Bravo drives Don't clunk into gear, Nor do TRS or Speedmaster drives...<br />
So, Baja, what does that have to do with AZMatt's post? He has neither, he has an Alpha drive.<br />Are you suggesting he change engines and drives to get an old TRS or Speedmaster so it won't clunk if the rpm is too high? Or maybe repower with a bigger engine so he can get a Bravo?<br />Even with those systems, to high an idle, and they will clunk...... Trust me.
I was just pointing this out to others who might be reading this post with these drives.. the above listed drives will not clunk at a Normal idle. so if one has a drive as listed above and it clunks. you have a problem.. <br /><br />BTW.. My Dock neighbor's 38' Cigarette has bulldog 540's and speedmaster V drives. engines idle at 1500 and no clunk at all. gotta love Velvet drive trannies :D
 
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