36i engine and sterngear

[kev]

Hi,

I'm having my 2007 36i lifted in a few weeks time for its annual scrub and antifoul. I've owned it from new and I'm anticipating that this year I will have to replace some parts on the sterngear. Can anyone assist with some questions I have please?

The cutlass bearing is almost certain to need replacement, as I last did this about 3 years ago - but as the boat is still in the water at the moment and I'd like to order a replacement before it gets lifted (I forgot to take any measurements last time, and I've since discovered that ASAP Supplies sell them at half the Jeanneau cost), would anyone be able to let me know the dimensions? (I only know the shaft diameter is 25mm, but there are several lengths and outside diameters to choose from).

As well as this, the Volvo shaft seal is still the original item, so I am reluctant to trust it much longer and am thinking of replacing it with a PSS dripless seal. A lot of people seem to like this make, and to me it seems a more elegant engineering solution as it essentially fails in a safe mode unlike the Volvo which could sink the boat if it fails. Has anyone have any negative experiences with the PSS seal?

Lastly the engine mountings on my Yanmar 3YM30 have sagged considerably over the years (as is usual it seems). I've had the engine realigned several times to make up the difference. Can anyone say how much minimum clearance is advisable between the two halves of the mounting before they should be replaced?

Many thanks,

Kev.

[so36idavid]

Hi Kev,

I have the same boat and I'm also planning on replacing the cutlass bearing and stuffing box on my next haul out. So when you do get the dimensions on the bearing I'd appreciate it if you'd pass them on. I plan on putting in a new Volvo stuffing box just like the one coming out. They're inexpensive and dead simple. Mine has lasted 7 years and 750 hours and I'm only replacing it as a precaution. I have friends with the PSS unit and they're a lot more complex to install and maintain. Plus I don't see how any stuffing box can "fail safe". I guess it depends on the failure modes you're anticipating?

The engine mounts on my Yanmar are very soft and the engine tends to vibrate a ton when at idle. My Yanmar guy says that they're like that for a reason and to just leave them in there. I haven't had any alignment problems, but then again I haven't looked .

David 

[kev]

Hi David,

If nobody has this cutlass bearing information already available, I will take measurements when the boat is out during the last week in May and will certainly post the dimensions on the forum.

I agree with you that it is a close call between the Volvo and PSS seals, and it's a bit like Marmite (for the benefit of others outside the UK, I don't know whether this "food" choice is available to you, but you either love it or hate it !!!).

My concern with the Volvo seal is that it will wear a groove in the shaft and there is no way of adjusting the length, so eventually, the shaft will need to be replaced and/or the seal will stop sealing effectively on that shaft location. Also when those lips eventually allow water through, I will have no way of stopping it until the boat is lifted.

On the other hand if a PSS bearing face allows water through (highly unlikely anyway), as long as I'm not actually motoring, I can always seal around it with amalgamating tape to prevent water ingress as a temporary measure to buy me time.

Agreed though that a bellows failure for both Volvo and PSS will have the same drastic consequences and be as difficult to resolve for both types.

WRT the engine mounts and alignment, you may not have noticed if you haven't changed the cutlass bearing before, but when you get around to removing the cutlass bearing, it will be immediately apparent to you if the alignment is not correct!!! With the rubber bush removed, you will probably find that the shaft is pushing down hard against the bottom of the P bracket tube....i.e more than just resting on it under it's own weight. When I had my alignment adjusted and replaced the cutlass bearing last time, it made a big difference to the noise levels inside the boat - the engine sound changed from a thundering to a purring. I noticed last summer that the noise had got very loud again.

I also think that the soft engine mounts are probably a good thing, for the reason above. The Yanmar mount consists of an inverted "U" with the bolt attached to the engine flange which sits over the top of a smaller inverted U bolted to the bearers, with the rubber blocks separating the two parts. I have noticed with mine that there is only about 5mm clearance between the two metal "U" shapes, so my question is whether this is still sufficient, or what is the minimum clearance that is advisable....or do I just leave them until there is metal to metal contact as the engine vibrates?

regards,

Kev

 

[ianpowolny]

Kev,

Here's a place to get the info on Volvo stuffing boxes. Just changed ours out after 7 years. Surveyor told its a 5 yearly job. I had a mechanic do the job. Too tight a place for me to get in to.

www.falmouthyachtbrokers.co.uk/shop.aspx?REF=Volvo+Penta+Rubber+Stuffing+Boxes

Ian

[so36idavid]

Kev,

Thanks for the info. If you do get updated measurements please pass them on here.

David

[no3l]

Hi All,

Attached is a drawing with dimensions of the cutlass bearing from a 2008 SO36i.

Please note that these are taken from a bearing I replaced and that I did not have a proper calipers when taking the measurements but they should be ok for chosing a new bearing. I will update when I get access to a calipers.

Does anyone have the part number for the bearing?

Regards
Noel

SO36i Cutlass Bearing.odg (10.5 KB)

[no3l]

Hi All,

Update to my last post, I found the attached picture on a post by Landseer, as far as I can tell the information on the label is:

Part number: 954855
Description: Cutlass Bushing 25x36x80+L R,
Baque Hydro D25/36 EPAUL
Dimensions: 25x36x80



Attachment Deleted


Regards
Noel

[kev]

Thanks to all of you for your inputs.

It looks as though the cutlass bearing I can get from ASAP Supplies (SHAFT BEARING BENETEAU 25x36x100mm Part No. 809916) will do the job. It will be slightly too long, but I don't think this will matter, or I can cut it down if necessary .......a saving of £20 on the Jeanneau price! I will let you know how I get on with it. Cutlass bearings of this type do seem to be consumable items, but at this price I have no qualms about renewing it every second year, which seems to be typical interval at my usage level.

As a coda on my jitters about the engine mounts, I discussed them with my local Yanmar agent (French Marine Motors) who have done some good work for me in the past, so I tend to trust their advice. It appears that they very rarely have to change Yanmar mounts, despite their reputation for softness. This seems to chime with what David says. Their experience is that the mounts only usually fail if they have been soaked with diesel or oil, or if the metal has been allowed to rust. It seems that the clearance I'm observing is pretty much what is expected on a bedded-in mount. His other comment was that if the clearance isn't sufficient, I would recognise it instantly since it would sound as if someone is banging on the hull with a hammer!! On that basis I will leave well alone for now and just check the alignment.

Regards,

Kev.

[kev]

I think I've reached a decision on using the PSS seal, provided I can buy one that fits.

I've measured my sterntube at 42mm diameter. Could anyone who's fitted a PSS seal please let me know which size you used?

My sterntube seems to sit just above the upper limit of the 1 1/2 inch PSS seal for a 25mm shaft, so will it stretch enough? The next larger size at 1 3/4 inch seems way too big and seems likely to need a reducer sleeve, which doesn't seem a good idea.

regards,

Kev.