VP 2003 gearbox

kalanka

Well-Known Member
Joined
21 Jan 2005
Messages
273
Location
North West Scotland
Visit site
1988 Volvo penta 2003

Recently gear selection has been erratic - I can push the control lever but sometimes there is no drive to prop. After a few attempts drive is engaged and appears to operate normally. Sometimes problem confined to forward with reverse OK. sometimes only reverse won't drive but forward will.

Gearbox oil level correct. Oil clean.

Any suggestions? I shall look at the linkages first.

I am a long way from any capable engineer

Thanks
 
Has the gearbox to engine spline conversion be done, due to the lack of shock absorption between the engine and gearbox and engine drive the splines on the connecting shaft wear away, possibly causing the problem you mention although I would have thought that if it failed you would not get any drive. This conversion has been dealt with many times before I am sure if you put VP gearbox drive conversion into the forum search it will come up with loads of posts. The conversion is a good one and is a lot cheaper than anew gearbox and it has rubber bushes in it so should last for ages. It means taking the gear box from the engine and removing the drive shaft and sending it to DB marine they machine it and send it back with all the components to re assemble it when I did it I think it was around £90 but that was many years ago try this link
VP 2003 spline problem
Regards Mike.
 
Last edited:
Yes you want to check the box with the gear cable disconnected as controls often give problems
The spline problem usually not usually intermittent but the the cone clutches do give problems and more usually as you discribe
 
Yes you want to check the box with the gear cable disconnected as controls often give problems
The spline problem usually not usually intermittent but the the cone clutches do give problems and more usually as you discribe

+1 to check the operation of the gear shift with the cables disconnected.
 
Thanks. Cable Linkage was a bit sticky After freeing and lubricating changing seems better but time will tell. Haven't yet tried without cable - too rolly at present

Is the general opinion that the spline conversion is a good thing?

I am anchored off Dominica so not likely to find a spline specialist here........
 
I don't believe that spline wear would give the symptoms the OP described. When the splines go, there's simply no drive.
 
I did it I think it was around £90

jeez that was many years ago Mike...I did it two seasons ago and got no change from £500 !!!

Not to mention having to insure the shaft or £1,200 (VP replacement price) in case the courier lost it in transit :)

jr
 
Is the general opinion that the spline conversion is a good thing?

It's vital Kalanka ..... when it goes you lose all drive, instantly and without warning .....and sods law says it will happen at time you need drive the most. When I pulled my gearbox out the splines were so close to stripping I'm amazed I made it from my berth to the lift out hoist. It is possible of course yours may already have been done.... although you'd nee to remove, or at least slide the gearbox back enough to check

jr
 
It's vital Kalanka ..... when it goes you lose all drive, instantly and without warning .....and sods law says it will happen at time you need drive the most. When I pulled my gearbox out the splines were so close to stripping I'm amazed I made it from my berth to the lift out hoist. It is possible of course yours may already have been done.... although you'd nee to remove, or at least slide the gearbox back enough to check

I'm not convinced "vital" is an appropriate word for spline conversion. There are lots of theories about this spline wear, from absent lubrication on assembly, to harsh use of gearchange. The problem initially became evident on charter boats, where harsh gearchanges are par for the course. I doubt very much whether every potentially affected gearbox has been modified, so there are loads out there that have done maybe 30 years service without problems. It's wise to have a look at the splines, certainly, but the problem is rather over-stated.
 
I had same problem on granada 375 but eventualy lost all drive .Turned out to be stripped bevel gears in saildrive.Had eventfull sail from cork to liverpool marina.I purchase 2nd gearbox and saildrive.If its you gearbox I have a spare in the garage
 
Well sorting out a very floppy cable link seems to have fixed it but you guys have worrying about my splines!

Are the splines the connection between engine and gearbox or gearbox and shaft?

How do I inspect?
 
Well sorting out a very floppy cable link seems to have fixed it but you guys have worrying about my splines!

Are the splines the connection between engine and gearbox or gearbox and shaft?

How do I inspect?

The gearbox has a splined shaft which fits into a splined hole in the flywheel. To inspect, you need to undo cooling pipes to the gearbox, undo the propshaft coupling, slide propshaft back, undo bolts holding gearbox, and pull the gearbox off the engine.
 
Well sorting out a very floppy cable link seems to have fixed it but you guys have worrying about my splines!

Are the splines the connection between engine and gearbox or gearbox and shaft?

How do I inspect?

Look at the link in my earlier post at #6 but note the engine number after whch it does not apply anyway.
 
Top