DP-G Prop and nose cone questions

[jon and michie]

Hi - Last weekend when I had the joyous task of cleaning my props I noticed that where the nose cone tightens up against the first smaller prop there wasnt a washer and within the prop near to where the hole for the shaft is there is a stainless type ring which is slightly damaged.

should there be some sort of washer/spacer between the prop and nose cone and is there a replacement ring that fits into the prop ?

2nd question - last year was my first year for removing the props - which took a bit of persuasion after which I fully cleaned the driveshaft and put plenty of grease on.
When I came to take them off last weekend I found that I didnt need to engage the gears and the nose cone and second nut came off relatively easy and found that the props just required a gentle tap with my hand. last year I torqued up the bolt and nut as specified in the volvo manual. --- is this because I totally cleaned the shaft and put plenty of grease on and is quite normal with being looked after properly or was I lucky not to lose my props.

many thanks for any advice
Jon

 

[BruceK]

Hi - Last weekend when I had the joyous task of cleaning my props I noticed that where the nose cone tightens up against the first smaller prop there wasnt a washer and within the prop near to where the hole for the shaft is there is a stainless type ring which is slightly damaged.

should there be some sort of washer/spacer between the prop and nose cone and is there a replacement ring that fits into the prop ?

2nd question - last year was my first year for removing the props - which took a bit of persuasion after which I fully cleaned the driveshaft and put plenty of grease on.
When I came to take them off last weekend I found that I didnt need to engage the gears and the nose cone and second nut came off relatively easy and found that the props just required a gentle tap with my hand. last year I torqued up the bolt and nut as specified in the volvo manual. --- is this because I totally cleaned the shaft and put plenty of grease on and is quite normal with being looked after properly or was I lucky not to lose my props.

many thanks for any advice
Jon

Oh no. Ask me I am forever loosing that rear prop . Ask Roy (Seastoke) he dines out on that fact every time we spar. Use Locktite when putting them back together. Dont be shy. Mine have stayed on since using it. (although I am DP-D your prop set of spacers and nuts look like mine)

Have a look for your prop type here: https://www.marinepartseurope.com/en/volvo-penta-cat-7744570.aspx
This is for J series

 

[BruceK]

A possible factor in why mine may have loosened before using Loktite is my props never stop windmilling except for slack water. The estuary moves on average 3knts constantly and sometimes more.

 

[dpb]

Having lost a prop and cone a few years ago I took the advice of our local Volvo mech which was to use new locknut and washer each time and to be sure to torque to spec..
I think jamming a block of wood under the prop blade rather than using the gears would be kinder on the drive line mechanism.
Coming apart easy when maintained yearly was my experience.

 

[BruceK]

That would be for the forward prop not rear. I have never had or heard issues about the forward prop coming loose or even off. There uses to be a castle nut before the current "nylock" nut (which like all nylocks are use once). The castle nut was prone to coming loose and if those nylocks came loose yes I could imagine it would have an impact on the forward spacer of the rear prop. Neither however accounted for my losses.

 

[Scubadoo]

Every year a clean the prop shaft with a wire brush and a small amount of white spirit (away from the seals), then I use quite a bit of prop grease on the shaft and to the seal and never had a problem with removing the props a year a later. I simply hand tight the nuts and cone very tight when fitting, this method has served me well for 20+ years without losing a prop.

 

[dpb]

That would be for the forward prop not rear. .

It was the rear prop.

 

[BruceK]

It was the rear prop.

But there is no locknut on the rear prop? There is the cone assembly and locking bolt.

 

[dpb]

True enough....I meant bolt and washer!

 

[BruceK]

That could make sense. I have always been reusing the old bolt. I wonder if it's one of those stretch bolts.

 

[dpb]

That could make sense. I have always been reusing the old bolt. I wonder if it's one of those stretch bolts.

Apparently it is.

 

[BruceK]

................And to think of all those Stainless steel props littering Conwy channel for want of a new bolt :ambivalence:

 

[jon and michie]

Right as I have a bit of time I have some pics.
The first one was taken a couple of years ago which I fitted and I didnt appear to have issues with.


Now this was taken a couple of weeks ago with the numbers lined up



appears to look okay at first



Then after turning by hand



The above to me does'nt look right so when I get back to my boat I will re position the rear prop

Thank you for the replies so far

jon

 

[jon and michie]

Bump

 

[jon and michie]

Right as an update - I got down to the boat last weekend and re alighned the props setting up the larger forward prop with the volvo markings at 12 o'clock.
then I placed the smaller rear prop with its volvo markings at 6 o'clock and now they look right.





after rotatoation

 

[AdeOlly]

Yup - in your earlier post you had one prop on backwards It looks correct now. The teeth on the inside of the prop are only half length as they are on the shafts, so in theory prop spins if put on the wrong way round.

 

[jon and michie]

believe it or not the prop went on th same orientation - just in a diffrent position on the splines
jon

 

[BruceK]

I dont see how you can use markings on the prop themselves to align as the prop can and does slip or at least creep on the rubber bushings of the hub...?

 

[jon and michie]

Bruce - I read about this method on the Internet and just out of curiosity followed it seems to work this time.
Jon

 

[AdeOlly]

believe it or not the prop went on th same orientation - just in a diffrent position on the splines
jon

looking more closely I can see that now .. sorry.