Trailer wheel-bearing (boat related)

Bunchats

Bunchats

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Boat trailer -

I had new suspension and wheel-bearings put on two years ago.

Trailer has only been used for local running.

Wheels had very short dip in salt/fresh water and were washed off.

Mechanic who did the new suspension now says the bearings are shot and need replacing.

Trailer has done no more than 50 miles in that time and has stood in the shed through the whole period.

Has anybody any experience of this - is it genuine or are they lookig for work.
 
As well as noise, check obviously for play, i.e the wheels should not wobble.

When I got myboat, on it's trailer, all 4 wheels wobbled. A clear lack of maintenance by the previous owner. All tightened up okay but two are noisy so next summer when the boat's back in the water I will replace the 2 noisy ones.

I really can't think just 50 miles would trash them. Did whoever fitted them completely forget to put any grease in?
 
You do not mention the time between immersion and the bearing problem (nor what type of bearing), but many bearings are supplied without waterproof grease.

When I fit new bearings I always remove the grease as supplied and replace with waterproof.

Also, If they are taper rollers you can remove them and see if there are marks on the surface.
 
would think that two seasons is fairly good life for a set of 'road worthy' bearings. have been in a dive boat syndicate for 18 years and during the time we used to move the boat a lot, it used to eat bearings. Now we just keep it near to the launch site so we don't mind about bearing condition so long as the wheels will turn and that still means new bearings every few years. the problem is that when you tow it to the site the wheels warm up the grease thins and clears off the bearings etc then you plunge it into salt water, this floods and contaminates the bearings and the grease and no amount of hoseing down afterwards will remove it. now left to sit in this salt the bearing surface's pit and rust and bingo they're shot. they will still turn and move easily but are shot and if you can feel any graunciness at all the they are not really fit for the road anymore. best practice if you want to play is to let the wheels and bearings cool right down before immersion and also to pump in more grease( though this has issues on braked trailers) before and after immersion too. In the end though you'll just find its easier to change out the bearings on a regular basis, and not very expensive if you do it yourself! now brakes and drums and wheel rims too are a different matter
 
ean_p said:
the problem is that when you tow it to the site the wheels warm up the grease thins and clears off the bearings etc then you plunge it into salt water, this floods and contaminates the bearings and the grease and no amount of hoseing down afterwards will remove it. .....

best practice if you want to play is to let the wheels and bearings cool right down before immersion
Click to expand...

Good points. What boat does the OP have?

Mine's a small sailing boat, so once we get to the slip, there's the mast to put up and rigging to sort out, so it's probably an hour before we then back the trailer into the sea, plenty of time for the bearings to cool down.

Likewise when taking her out, there's plenty of pottering about on the boat to do first, again allowing time for the bearings to cool down.
 
If the bearings fall apart when you dismantle them, it is far easier to buy a complete hub and bearing assembly (it was £4 more than just the bearing when I did it 3 weeks ago). Definitely go for waterproof grease (about £7 a pot and you might need one pot per assembly).

If there's any doubt at all I would change them, especially if you're planning to go more than a mile or so. Not nice to have a wheel melt on you. Repair/recovery is not straightforward at the roadside.

Good luck.
 
Trailer bearings

Maybe when they were fitted they were not re-adjusted after a short while. Sometimes the bearing do not tighten up correctly when first fitted. A short journey and re-adjust to take up any slack is a good idea. You should now jack up each side, spin the wheel and listen, see if there is any rocking motion in the wheel, if you can rock it, tighten the bearing till the wheel binds then slacken off till the wheel stops binding. Spin the wheel again and listen if it is quieter than before you just may have fixed the problem. If the noise has gone then grease up fully and check the bearings after each journey. If they are really gone then there will be a noise when pulling the trailer plus the bearings may get hot. Running the bearings with too much play may ruin them after just a short while. Good luck.
 
If you are going to put the trailer away without use for any length of time it makes good sense to remove the hubs and clean the bearings, putting new grease in, before storage. Sealed bearings are a pain on this score.
It's the water and the air together that start the corrosion. So put them away clean.
 
Bunchats said:
Thanks - will do that and listen to the noise if any - much appreciated.

It's a bit odd for this to happen when the wheels have done no mileage I would have though.
Click to expand...

It is unlikely that the mileage will have any effect on a boat trailer bearings. The bearings on my tow vehicle have done 110K miles. It is the type of use. Dunked in water sometimes salt water maybe sometiimes when hot.

I have just serviced the bearings on my 4 wheel trailer this afternoon.
They don't do badly, the trailer goes into fresh water mainly, its a yacht so usually at least an hour between arriving and dunking, usually 3 or more if mast going up.

Trailer usually taken home empty during season and stored in a nice ventilated barn. So bearings did not need anything doing to them.

Your bearings may well have failed, were they set up right in first place? tapered bearings should have a little play in them. Tightening the hub nut torque to 20ft lbs then back off a quarter of a turn or so to give 0.1mm float, which I take to mean you can push the hub in and out very very slightly. At least that is what the Indespension book says.

I also used Keenol grease which is a water resistant grease now sadly no longer available I believe.
 
grease, grease and even more grease is always the answer. My own take is that any bearing that failed in two years has not been properly maintained.
 
Trailer bearings

Your mechanic is probably treating your bearings like those on a car. ie they should be in perfect condition and suitable for high speed driving for 100s of thousands of Kms.
Boat trailer bearings are different story because they get dunked.
The only practical answer is for you to do bearing service yourself. I have tapered roller bearings from an old larger car front wheels. I can pull the wheel and bearings in about the same time as it takes to jack the trailer up. Just a few minutes. I knock the cap off the bearing and pull the split pin. I don't spread the ends of the split pin as it sits vertical with gravity holding it in. The pin is long enough that it is trapped in place by the walls of the cap. (this may raise some eyebrows). So spread the pin ends if you are worried.
The nut is quite loose and after removal the outer bearing comes out. The wheel and hub come off the axle to reveal the inner bearing hopefully still in the hub.
At this stage it is very obvious from the colour of the grease if water has got in. If the bearings are rusted it will be obvious.
I find just a bit more grease and a clean up and reassemble is all that is needed.
If you do this after each dunking.
In my opinion if you only do short trips low speed then a pretty rough bearing can be used for a long time provided it doesn't get too hot and has plenty of grease.
Just keep pulling the bearings olewill
 
I once bought a boat on a trailer and a wheel bearing collapsed when I towed the boat home forcing me to leave the boat at a Quick Fit Depot 80 miles from home, (they do not stock boat bearings) I am a bit paranoid about boat trailer wheel bearings. So when I arrive at the slipway, I grease the bearings before launching, then I grease them again when I pull the trailer out of the water, then I grease them again after I get home, and did I mention, before I even set off I grease them. Grease is cheap.
My boat trailer axles (in my opinion) have a design fault. When you grease them there is a grease relief valve at the rear which is supposed to eject any excess grease when the hub is full. The trouble is the boat trailer goes in the water, salt gets on the relief valve and it ends up sticking, so when you grease your hubs with the valve stuck, the hub pressurises, the internal seal expands and your pumping away filling the brake drum with grease.
 
I have had a couple of problems with trailer bearings.
You need to learn how to look after the bearings yourself as your mechanic won't be there when things go pear shaped on a trip.
Grease, grease and more grease is not the way to go, you can overpack the bearings. Clean off old grease and replace with fresh dry grease is good. Do this frequently.
Having the right tension is good too, not too tight, not slack, a little bit of play as David says.
Always carry spare bearings and have the tools to change them on the road. A set for my trailer single axle costs £30, I keep 2 sets so I still have spares when I have had to use a set.

Other than that, it's a doddle.
 
aquaplane said:
, you can overpack the bearings.
Click to expand...

Yes you can overpack the bearings, but when the trailer salesman says that you cant overpack the bearings as the axle has a pressure relief valve to stop that happening you take him at his word (silly me) so you start pumping and on the wheel hubs where the relief valve hasent siezed up, the excess grease is ejected through the relief valve on the other side of the wheel to fall on the floor. But you only know when the relief valve is stuck when no grease is ejected and by that time your seal has been moved backwards with the pressure and your hub is consequently getting full of grease and all over your brake shoes.
 
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