Volvo shaft seal

[mikegambling]

has anyone found a satisfactory method of greasing the seal as one is required to annually /forums/images/graemlins/confused.gif

 

[jerryat]

HI mikegambling,

This is what I do every year just before launching. Take a good quality i.e. reasonably thick plastic bag. Cut one corner off, so that you have a triangular piece about 75 x 75mm. Put the grease (I've used Blakes seacock grease for the last 16 years) into the corner. The recommended amount is about 1 cc, but put a fair bit more in to allow for what escapes during the process.

Cut the corner off to give you a slot about 6-8mm long. Squeeze hard and lift the gland up to open up a gap above the shaft and insert the cut corner in this gap as far as you can. Roll up the hypotenuse (the longest side of the triangle, opposite the cut) to squeeze the grease into the gland. It's a bit like using one of those icing squeezer thingies my wife tells me.

A little grease will be lost as you squeeze it out, but the vast majority will go into the gland where you want it. Wipe off the surplus and job done!!

This really does work, so have a go!

Cheers Jerry

 

[gjeffery]

I use Volvo grease, unfortunately supplied in fairly small tubes.

I release the two clips holding the seal, slide the seal a few inches along the prop shaft. Apply grease to the shaft, slide seal back, and tighten clips. That way, I also get a good look at the seal.

 

[theia]

if you are going to move the seal make sure that you insert the plastic cap supplied when new first. You could damage the seal or even worse, allow it to reverse when returning it and eventually losing the watertight seal

 

[RJD]

Hi, I used silicone grease last season and found that thenegative pressure on the outboard end of the seal sucked air past the seal. This caused the cutless section of the seal to rumble as if a bearing had gone in the gearbox! Volvo grease cured the problem and I have had no further problems... The icing bag approach sounds good!
Tony P

 

[reeac]

My marine engineer guru says that it's easy to damage these seals by trying to get grease into them and that they last perfectly well with an initial grease during installation and then just the usual "burping" to remove air when the boat goes into the water after being laid-up.

 

[jerryat]

Hi reeac,

I think you were being given very bad advice. The installation instructions specifically mention greasing once a year, and carrying out this regime has been proven, for me, by the fact that the seal I've just removed as part of a big refit was exactly twenty years old (i.e. the original) and had never leaked a drop. Of course, the reason for greasing is that there are two lip seals in the VP unit. The outboard end is lubricated/cooled by sea water, but the inner end isn't - hence the need to grease as it would run dry otherwise.

If you try the method I outlined earlier, you can envisage what happens: the corner of the 'bag' is flat, while it's flat you lift the seal to produce a slight gap in the same way you do when venting it and slide the cut cut of the plastic bag into this gap.

At this stage I usually release the seal but ONLY so that I can roll the long edge of the 'bag' over itself to help provide a seal to stop the grease squeezing out that end, instead of into the VP seal.

Once that's done, lift the VP seal again, and squeeze the grease into it. It takes surprising pressure (hence needing a good quality bag that doesn't burst!) but works extremely well. When you consider that the whole operation takes less than 10 minutes, it doesn't make sense NOT to do it IMHO!!!

The VP lip seal is in no way damaged by this method, and indeed, the method shown in my original instruction is exactly the same. There was even a plastic sachet of grease provided that you cut the corner off!!

Cheers Jerry