Volvo 275 outdrive Thump when shifting into Reverse

"I"ve noticed my outdrive

"I"ve noticed my outdrive thumps going into reverse. When shifting into forward it may thump a little or may go in smooth. Is this something that needs adjusting in the gearbox? Is it a sign of wear? I'd like to fix it if I can before it gets worse.

By the way, Idle is set at 650 rpm AQ260. retaining pawl works good.

Thanks for any help."

"It is normally a sign that th

"It is normally a sign that the 'wear ring' at the bottom of the vertical shaft need replacement.
An easy job, but the top unit needs to be dismantled.
Get a manual, measure the clearing between the upper nut and bearing. If out of tolerance - dismantle and change. Whatever you do, do not fall for the trick of putting on a thicker nut!!!"

"The drive parts by now may be

"The drive parts by now may be wearing some. You may have a little more slack between the set pin and the receiving area of the main suspension fork (FWD shift clunk) and a little more slack in the REV latch unit (REV shift clunk).
None of which is great, but it can be considered normal for this drive.

It can help some if you make sure that the return spring is in good condition and strong!
Also if the Latch Hooks are not stretched out and/or worn....... and as you mention, RPM set correctly.

Your cone clutch sliding sleeve/gear cup may also be engaging a little too much on the agressive side.

Question:
Have you had the upper unit over-hauled, checked, any changes made, etc?
Too much vertical shaft end play from a worn split ring keeper can (not always) contribute to a harder than normal hitting shift!
If typically running LH prop and/or a Duo Prop, have this looked at! Replace if need be!

Edit: I see that Morten just posted while I must have had my page open. Yes, ditto that procedure. That is precisely what I am speaking about. This is a brass part..... subject to stretching over time.... and particularly when using LH prop or Duo Prop.
(this has to do with which "driven" gear is being used..... up-lift on shaft.... pressure on split ring!)

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"Thanks for the replies. I am

"Thanks for the replies. I am going to be tearing into the outdrive this winter and will address it then. I have not had any work done on the upper or any of the drive. I don't know the history. I do know that everything else seems worn out.

I'm not conviced this is a job I should take on. If I'm pulling apart the upper, I may as well go through it completely. I just can't find a good AQ mechanic in my area."

"captmello, I do have people

"captmello, I do have people (from areas where they can't find nor trust a local shop) ship these to me for repair. I am mainly into the AQ series drives. I am in Portland, Or.
If interested in this as an option for later this winter, click on my user name...... it will direct you to my email address.

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