Volvo SD120 sail drive not engaging

tawhiri

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HELP
I and am stuck in Rogozenice and my transmission will not engage reverse or forward. The cable is selecting correctly. but the prop just free wheels
Any ideas or where I can find A SERVICE MANUAL
tHANKS
 
No personal experience of this drive but- does the output shaft rotate as it should F/N/R but the prop not, splines or rubber cush drive at fault?

If so, a new prop /bush may be all that's required- hope its resolved soon.

Nick
 
Might be worth checking that the operating lever at the top of the gearbox, has the clamp onto the operating shaft fully tightened. If the bolt has loosened or broken, the lever will move back and forward but not transmit this movement into the gearbox.
 
Yes even removed the cable to try and engage manually, with no luck. I am beginning to think it could be the splines on the shaft. but the should have been warning signs?
Cheers
 
Unlikely to be the splines. If it is at the prop end then it will likely be the rubber bush that has come away from the prop hub. You might be able to check by diving and seeing if you can turn the blades while holding the cone nut which is screwed to the shaft. If the blades turn the bush has failed and a new prop should solve the problem.
 
I spoke to John from Kiwiprop yesterday. He said it is impossible to strip the spines with my small MD2020 engine, and indicated that the problem is most likely in the drive train. Possibly the gear at the bottom of the saildrive leg. The prop turns smothly and feathers corretly which reinforces his idea.
 
Unlikely to be anything in the bottom of the leg. More likely to be in the gearbox at the top end. If the bottom was broken you would still hear and feel it go into gear. It is more likely to be the selector or the clutch pack - although the latter usually seizes solid when it fails. You still need to check if the output shaft turns or not when the gear lever is in gear, not just the feathering of the prop which is done by waterflow, not mechanically.
 
Unlikely to be anything in the bottom of the leg. More likely to be in the gearbox at the top end. If the bottom was broken you would still hear and feel it go into gear. It is more likely to be the selector or the clutch pack - although the latter usually seizes solid when it fails. You still need to check if the output shaft turns or not when the gear lever is in gear, not just the feathering of the prop which is done by waterflow, not mechanically.

They are cone clutches in the 120 drives I believe. It seems unlikely that both forward and reverse gear selection would have failed unless it is the selector mechanism failing to move the sliding sleeve in either direction.

I agree very unlikely for anything to have failed in the bottom gear box .

It should be possible to confirm that the drive is being transmitted from the engine to the upper gear box by inspection via the oil fitting cap. Maybe also to see if gear selection results in the vertical shaft rotating

Upper gearbox exploded diagram: http://www.marinepartseurope.com/en/volvo-penta-explodedview-7746410-44-213.aspx
 
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It could be the dreaded Volvo gearbox spline problem depending on your engine number. Early 2000 series engines had a tendency to strip the splines on the gearbox input shaft without warning. See this thread for more details. http://www.ybw.com/forums/showthrea...et-and-splines&highlight=volvo+gearbox+spline

Luckily, I discovered the wear on mine before it failed and managed to fit the modification from DB Marine.

Edit - it's a problem on engine numbers earlier than 2300059128.
 
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It could be the dreaded Volvo gearbox spline problem depending on your engine number. Early 2000 series engines had a tendency to strip the splines on the gearbox input shaft without warning. See this thread for more details. http://www.ybw.com/forums/showthrea...et-and-splines&highlight=volvo+gearbox+spline

Luckily, I discovered the wear on mine before it failed and managed to fit the modification from DB Marine.

Edit - it's a problem on engine numbers earlier than 2300059128.

IIRC hat only applies to the 2000 series, not to 2010 2020 etc ????
 
Just to close this thread.
I was in fact the prop. The mechanic / Diver was correct.
I must say Marina Kremik have been the best support I could wish for, and done a very profesional job.
Thanks for all the info guys.
 
Just to close this thread.
I was in fact the prop. The mechanic / Diver was correct.
I must say Marina Kremik have been the best support I could wish for, and done a very profesional job.
Thanks for all the info guys.

Update much appreciated. Not everybody does that.
 
Hi, I aslo have a similar problem and would greatly appreciate advice. After hitting a submerged obstacle yesterday my engine will no longer go forward but does go in reverse, any ideas? (Volvo penta 2001 9hp and saildrive 120s). Thanks.
 
If you put the lever into reverse, the prop should free-wheel in one direction and not the other. Then if you put the lever into forward it will free wheel in the opsosite diretion to reverse and also not turn in the oposite direction to reverse. Of couse your engine is NOT running at the time. This is all done by hand, and proves that the transmission is engaging gears correctly.
Most likely the prop is damaged. Is it a feathering or folding prop?
 
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