Frozen duo props on DPS drive legs

Megs20Burt!

Megs20Burt!

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Hi,

we have just brought a twin engined sportsboat with Volvo DPS drive legs. I asked for the drive legs to be serviced, the yard doing the work rang me today and told me they have been unable to remove the props to get to the leg oil drain plug.
it would appear I have two options,
1. Use a pulley to try and remove the props,
2. Cut the props off.

has anybody any experience of this including these options?

any help would be appreciated.

thanks
 
Megs20Burt! said:
Hi,

we have just brought a twin engined sportsboat with Volvo DPS drive legs. I asked for the drive legs to be serviced, the yard doing the work rang me today and told me they have been unable to remove the props to get to the leg oil drain plug.
it would appear I have two options,
1. Use a pulley to try and remove the props,
2. Cut the props off.

has anybody any experience of this including these options?

any help would be appreciated.

thanks
Click to expand...
Has it been a dry stacked boat ?
I often have trouble removing props beca they are dry stacked the anodes don’t wear but the salt in the water corrodes the props to the shafts , sadly this is down to poor servicing , you say you have just purchased the boat , I’d enquire on the level of servicing as this will indicate when an oil change was last carried out .

I would also question what pullers the engineers have to carry out the job as I have in the past made up a very slim puller to pull off the rear prop , once that’s off it’s easier to remove the front one .
Suggesting to destroy the props is just ridiculous, I’d be asking them to stand down .
 
volvopaul said:
Has it been a dry stacked boat ?
I often have trouble removing props beca they are dry stacked the anodes don’t wear but the salt in the water corrodes the props to the shafts , sadly this is down to poor servicing , you say you have just purchased the boat , I’d enquire on the level of servicing as this will indicate when an oil change was last carried out .

I would also question what pullers the engineers have to carry out the job as I have in the past made up a very slim puller to pull off the rear prop , once that’s off it’s easier to remove the front one .
Suggesting to destroy the props is just ridiculous, I’d be asking them to stand down .
Click to expand...
Thanks for the rapid response.
I think the drive legs were last serviced in 2017. The boat has had little use since then from what I understand. The pre-purchase survey picked up a gimble bearing fault (which has been replaced) and the sea trial went well with the boat running nicely up to 28 knots. You mentioned what puller they are using, the workshop manager is on holiday this week and I wonder if he is the engineer with the experience? The yard is very busy and low on staff, maybe whoever was put on this job doesn’t have the experience or knowledge?
appreciate the advice VP?
 
If you have easy access , takes days a bit at a time but drop a bit of freeing up agent around on it .
The steel stud ( your shaft(s) stubs and alloy ( your props ) the corrosion issue occurs with trying to remove alloy cylinder heads on alloy blocks that have bolted down with steel bolts .If there’s been a gasket seeping....water + alloy + steel dissimilar metals etc etc .
A puller rig + PB blaster ,penetrating oil or WD 40 applied regularly does the trick .
Some say make your own stuff with white spirit + olive oil .......kid you not mix up the ratios to suit .........quite a lot of spirit to start with to penetrate at first then add more oil as the days goes by .
Just takes time .
Eventually the spirit part works it way in between dragging the oil and they separate.


Generally
Anodes need Immersion in a salt solution erh ,,,,seawater to work a moot point amongst a few on hear who have fitted a “Tm Bodgeflow “ To there anodic protected engines .
 
Correct me someone if I am wrong but does any leg have an oil drain plug that necessitates removing the props?

To the OP I have had some success in removing salt encrusted shaft grease which can cause the props to stick after creating a cement by simply pouring boiling water down the shaft splines with the leg raised to melt and dissolve any grease cum salt cement. It wont work on corroded hubs though and cutting them off is a last known resort should you not get them off with a gear puller.
 
Try using a heat gun on the root of the props.
This has worked for me in the past.
You only need a couple of thou. expansion and they should come off.
 
volvopaul said:
Where is this ?
Click to expand...
BruceK said:
Correct me someone if I am wrong but does any leg have an oil drain plug that necessitates removing the props?

To the OP I have had some success in removing salt encrusted shaft grease which can cause the props to stick after creating a cement by simply pouring boiling water down the shaft splines with the leg raised to melt and dissolve any grease cum salt cement. It wont work on corroded hubs though and cutting them off is a last known resort should you not get them off with a gear puller.
Click to expand...
sure do .
 
volvopaul said:
sure do .
Click to expand...

Yes Spannerman has already confirmed but now I'm really intrigued as to why Volvo made this move. Having to remove props and no doubt the shaft anode too seems a rather long winded and inconvenient way of changing oil. Would you know their rationale behind it? Are the torpedoes narrower as a consequence? What benefit?
 
BruceK said:
Yes Spannerman has already confirmed but now I'm really intrigued as to why Volvo made this move. Having to remove props and no doubt the shaft anode too seems a rather long winded and inconvenient way of changing oil. Would you know their rationale behind it? Are the torpedoes narrower as a consequence? What benefit?
Click to expand...

probably to force you into removing props and greasing them as part of the service instead of just leaving them in place for years causing them to seize.
 
Boat2016 said:
probably to force you into removing props and greasing them as part of the service instead of just leaving them in place for years causing them to seize.
Click to expand...

I always thought the ring anode behind the props served this purpose.

BTW, I have had to cut a prop off before. It had been on for two years only and defied any and all attempts to remove it. Probably could have got it off with better kit, but I opted for cutting it as it was near end of life anyway.
 
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