Brunton autoprop problem help needed

Hi Pagetslady,

I have a Corsair with a Beta 38, (700hrs) PRM gearbox and an Autoprop. I find that it spins in neutral, with anything over 3knots, only seems to lock in forward. Typically get and extra .3-.5 knot when shaft locked.

Good luck..
 
My autoprop manual is extremely clear:

"Do I need to do anything to make the Autoprop 'feather' under sail?
All you need to do, is to stop the engine whilst motoring in ahead, and thereafter leave the engine engaged in ahead. With engines fitted with some hydraulic gearboxes, engage your shaft lock. Your Autoprop distributor will be able to advise you if this is necessary."
 
I have an Autoprop H5, on a 1GM10 with the KM2P-1 2.62:1 gearbox. It holds the propshaft fixed in ahead gear, but not in astern. If I leave it in neutral, the prop starts rotating at around 4 knots.
 
rgarside said:
I have an Autoprop H5, on a 1GM10 with the KM2P-1 2.62:1 gearbox. It holds the propshaft fixed in ahead gear, but not in astern. If I leave it in neutral, the prop starts rotating at around 4 knots.
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There is something odd about the way that this gearbox (I have the same one) locks the shaft. My normal practice is to put the gear into reverse as soon as I turn the engine off, which will arrest shaft rotation immediately. However, recently I have forgotten to do this on a couple of occasions, only realising that the shaft was still rotating some time later when I heard it from the saloon. I find that putting the gear into reverse at this stage has no effect, whereas putting it into forward stops the shaft.
 
vyv_cox said:
There is something odd about the way that this gearbox (I have the same one) locks the shaft. My normal practice is to put the gear into reverse as soon as I turn the engine off, which will arrest shaft rotation immediately. However, recently I have forgotten to do this on a couple of occasions, only realising that the shaft was still rotating some time later when I heard it from the saloon. I find that putting the gear into reverse at this stage has no effect, whereas putting it into forward stops the shaft.
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Interesting , we have a Volvo D2 40 with a sail drive S130 with a Volvo folding prop , stopping the engine first the prop with still go around at speed ( we would be sailing at some speed at this stage ) and when putting it on rev it make a loud chunk , I have emailed Volvo in the past asking it it wouldn't be better of we stop the engine in gear and them put it in rev , there answer has been not to stop the engine in gear and don't worry about the chunk , personally I don't think that right but you would expect Volvo to know what they are talking about , or would I ? What the panel opinion or this ?

www.bluewatersailorcroatia.webs.com
 
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vyv_cox said:
There is something odd about the way that this gearbox (I have the same one) locks the shaft. My normal practice is to put the gear into reverse as soon as I turn the engine off, which will arrest shaft rotation immediately. However, recently I have forgotten to do this on a couple of occasions, only realising that the shaft was still rotating some time later when I heard it from the saloon. I find that putting the gear into reverse at this stage has no effect, whereas putting it into forward stops the shaft.
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The logic of that is the prop has feathered so far that it is driving the shaft in reverse which possibly explains why the drag and turbulence is so high.
 
since my last posting here ,i change boat and also fitted and autoprop on an volvo 120 saildrive , see other thread.
what I found now is in rev the gearbox still turns , in forwards it stopped but i am unable to get it out of gear which mean starting it in gear , which i not too happy about , six Volvo dealers have given me conflict info about stopping it or not , so now I also a bit lost .
 
Pagetslady said:
Hi I have fitted a Bruntons Autoprop to my Westerly Corsair which I also fitted a new Beta Marine 35 hp engine. The problem is that when sailing I select astern to stop the prop rotating and feathering the blades. Ok this some times works but some times it does not, when the prop is turning the drag is amazing slows the boat down by at least a knot, it also causes steering problems. I have tried selecting ahead which sometimes this locks it but not always. On my old engine VP 2003 locking it in Astern was fine. Has anybody out there experienced this problem.

Regards Mike.
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Not reverse, leave it in forward gear - I was advised to do that when I fitted the Autoprop in 1992.
To relieve the puzzled - Yanmar boxes in forward, most others in reverse - has to do with the cone clutch gear-change.
 
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Hi this thread goes back a while. Since first asking the question here I have had a new gearbox curtesy I'd Beta, my original one was very noisy. But the locked shaft is still a problem that I haven't yet solved, I have considered a Shaft Lok from America which is very clever. Beta have explained that because the cones are held I place with oil pressure, it is necessary to run the engine ever few hours to replenish the oil( sound like rubbish) but that is why after a few hours running the prop starts rotating.
I think I will fit a shaft lock for next season.
Mike
 
charles_reed said:
Not reverse, leave it in forward gear - I was advised to do that when I fitted the Autoprop in 1992.
To relieve the puzzled - Yanmar boxes in forward, most others in reverse - has to do with the cone clutch gear-change.
Click to expand...

Although it depends whether you have a shaft drive or sail drive.

Yanmar advice for SD20 saildrive is to leave in neutral.

Richard
 
sailaboutvic said:
since my last posting here ,i change boat and also fitted and autoprop on an volvo 120 saildrive , see other thread.
what I found now is in rev the gearbox still turns , in forwards it stopped but i am unable to get it out of gear which mean starting it in gear , which i not too happy about , six Volvo dealers have given me conflict info about stopping it or not , so now I also a bit lost .
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I have a similar set up (Brunton & S120). Engaging forward stops the rotation, getting to neutral sometime takes a bit of effort getting it out of gear. I find that if the boat is moving at more than a couple of knots, then the rotational force of the Brunton makes it difficult to disengage the gears. Solution is either to wait until the boat speed drops a bit more, start the engine in gear or, using a bit of force, knock the engine out of gear. I usually start the engine in gear.
 
Ok here we go , Email reply .

Dear Vic,

We have fitted the Autoprop to thousands of saildrives now with very good results. The shaft does need to be locked to get the benefit of the Autoprop when sailing. To do this the engine does need to be locked into the ahead position to enable the blades to take the least line of resistance when sailing. To get it into gear whilst sailing with the prop turning and the engine switched off, can prove to be difficult at times and therefore we have said that it is easier to just stop the engine in gear, with the sails powered up. Furthermore, attempting to shift the gear back to neutral when sailing can be difficult, so we recommend that you first slow the vessel by heading into wind, this will reduce the moment on the propeller making easier to engage neutral, so that you can start the engine. In an emergency you can also start the engine in gear.

I hope this information has been of assistance. If you have any further questions please don’t hesitate to ask.

Many thanks.

Ok guys I hope this help other out .
 
I have a Bruntons 3 blader. This business of using the engine- gearbox combination to lock it drove me nutty. I found in the USA a manufacturer who makes a contraption to lock the shaft when under sail operated by a control cable. It is called a Shaftlock. Perfect.

My 3 blader is a right handed propeller. Therefore I have to remember when engaging the engine first of all to make a second's burst astern to free the lock then to neutral before engaging ahead to make way.

The result is a guarantee the prop will not spin when sailing when the Shaftlock is engaged. Marvellous to just hear the gushing noise as she cleaves through the sea free of unnerving rumbling noises caused by a spinning prop. Perfect. A glass of chilled champagne completes the delight.
 
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