PRM 260 Gear box shaft seal leak

[patria]

Guys I am looking for a bit of guidance on replacing the shaft seals on a PRM 260 gear box which has developed a leak which I think is one of the shaft seals, the output shaft seal. Do I "simply" dismantle the output shaft to pull it out the back of the box - then unbolt the seal carrier and replace the seal or do I have to dismantle the gearbox to replace the seal? ie is there a separate seal carrier.

Cheers

Patria

 

[Tanqueray]

Guys I am looking for a bit of guidance on replacing the shaft seals on a PRM 260 gear box which has developed a leak which I think is one of the shaft seals, the output shaft seal. Do I "simply" dismantle the output shaft to pull it out the back of the box - then unbolt the seal carrier and replace the seal or do I have to dismantle the gearbox to replace the seal? ie is there a separate seal carrier.

Cheers

Patria

Hi,

Here is the link for the manual from Peachment. Just click on 260 workshop manual. You need page 27 and a parts list / numbers are provided. Gearboxes are simple to overhaul.

PRM | A R Peachment

 

[captainboo]

Easy to do as said above. I have an earlier version of the gearbox but with a similar setup.

Look at page 44 of the above manual for a detailed cross section of the output shaft. You will need to find a way of locking the output shaft/flange to prevent it from rotating whilst undoing the output coupling nut as it will be very tight 250 lbf.ft! - I use a piece of angle iron bolted to the output flange that then rests on a block of wood against the hull etc. to prevent the rotation and then use a long breaker bar.

Once this is removed then just unbolt the carrier seal from the back of the gearbox and remove and then replace the seal. It is also advisable to replace the o-rings that go around the outside of the seal carrier and the one between the shaft and the flange.

If there is any wear to the output flange sealing surface you can get a Speedi Sleeve or equivalent ( SKF Speedi-Sleeve | SKF ) to rebuild the shaft surface. Alternatively if you note the position of the seal in the carrier you may be able to put it in a slightly different place so that the lip is on a different part of the output flange.

It is worth checking that you haven't got a leak from the pump where it mounts on the back of the gearbox which might be running down the back of the box and making you think it is from the output shaft. If this is leaking it can be removed in situ but access to the bolts is easier with the output flange removed again. There are two o-rings between the pump and the gearbox for sealing (B3 page 36).

You can get a full overhaul kit from ASAP: PRM Gearbox Spares, MT0382 Seal, Gasket and O-ring Kit (asap-supplies.com) or just get individual bits from local bearing suppliers or ebay if you measure the sizes.

 

[Boater Sam]

Easy to do as said above. I have an earlier version of the gearbox but with a similar setup.

Look at page 44 of the above manual for a detailed cross section of the output shaft. You will need to find a way of locking the output shaft/flange to prevent it from rotating whilst undoing the output coupling nut as it will be very tight 250 lbf.ft! - I use a piece of angle iron bolted to the output flange that then rests on a block of wood against the hull etc. to prevent the rotation and then use a long breaker bar.

Once this is removed then just unbolt the carrier seal from the back of the gearbox and remove and then replace the seal. It is also advisable to replace the o-rings that go around the outside of the seal carrier and the one between the shaft and the flange.

If there is any wear to the output flange sealing surface you can get a Speedi Sleeve or equivalent ( SKF Speedi-Sleeve | SKF ) to rebuild the shaft surface. Alternatively if you note the position of the seal in the carrier you may be able to put it in a slightly different place so that the lip is on a different part of the output flange.

It is worth checking that you haven't got a leak from the pump where it mounts on the back of the gearbox which might be running down the back of the box and making you think it is from the output shaft. If this is leaking it can be removed in situ but access to the bolts is easier with the output flange removed again. There are two o-rings between the pump and the gearbox for sealing (B3 page 36).

You can get a full overhaul kit from ASAP: PRM Gearbox Spares, MT0382 Seal, Gasket and O-ring Kit (asap-supplies.com) or just get individual bits from local bearing suppliers or ebay if you measure the sizes.

If you do remove the pump, make sure you put it back the same way up!