Corrosion on screws in winches

[TheBomber]

While servicing my sheet winches (Lewmar Evo No.8) last week I found some had rusty screw heads within. The screws sit beneath the stainless top plate, pass through plastic and fasten into the winch body (which I believe is an aluminium alloy). Once I’ve managed to get these out:
- do I just replace with stainless steel
- do they need something like Duralac on the threads?
- have I been unlucky, did Lewmar make a mistake or is this the inevitable price for neglecting servicing for a few years?

 

[PetiteFleur]

Looks like they are steel screws- probably BZP, (Bright Zinc Plated)which will always rust, particularly in a marine environment. I would replace with A4 stainless screws and Duralac or similar compound.

 

[thinwater]

I've never seen them like that. I'm guessing they are not factory.

If you are servicing the winch, grease should be enough. There should be no reason for Duralac. If 316 screws are rusting you need to service more often!

BTW, with SS in aluminum it should be the aluminum that corrodes (less noble) and the SS should be protected. I seriously doubt the screws are stainless. But I've never struggled to get screws out of a winch.

 

[vyv_cox]

Definitely carbon steel. Stainless steel will never corrode like that.

 

[TheBomber]

Thanks all - so shame on Lewmar then*. Surprised they even had carbon steel screws around to fit in error.

* I am the second owner of the boat, but the first only had it for a year and didn’t look to have used the sails much - so I’d be surprised if he serviced the winches at all, let alone removed stainless screws and replaced them with carbon steel.

 

[Neeves]

You were lucky in your timing - left a bit longer and removing the fasteners would have been crisis work! I find it very difficult to believe that Lewmar would not use the appropriate fasteners.

There are other people in the 'supply' chain, boat builder, commissioning agent as well as the previous owner. Your comment is correct - it would be very odd if Lewmar had carbon steel fasteners, at all. Nothing I can think of in the Lewmar inventory would need carbon steel fasteners - there would be no reason to have them in stock.

I assume you will be servicing all the winch(es) now. It will be interesting to learn if the others have the same issue.


To illustrate what happens - we bought a new yacht, came straight from the factory. It was commissioned by the company that sold us the yacht and there agent for the boat builder. The company had an identical yacht that they raced. I cannot recall the background but our yacht had a Gori prop and there was some issue with it. I contacted Gori and they said that the background I sent them, was incorrect. The unique number of the prop was much older than our yacht, like years incorrect. Gori had chapter and verse of the prop.

On commissioning the old prop of the older racing yacht was installed on our yacht and they had the new prop (after all how would anyone know . ). But you eventually get caught out - its pretty awful PR. It does make you wonder.

Jonathan

 

[Snowgoose-1]

I purchased some of those naff canvas tea cosy covers for my four winches a few years back.

It may be my imagination, but they seem a lot freer after a British winter. Water did seem to collect in some of them before the covers.

Definite upgrade from Tesco carrier bags.

 

[TheBomber]

Of the 12 screws across 4 winches, 5 are in this rusty state but presumably all are the same material. All of the non rusty ones unscrewed and I’ve managed to get 2 of the rusty ones out, but I’m going to have to buy something like an impact driver to persuade the remainder to turn. It’s still possible to do a reasonable servicing job without undoing them, it just wouldn’t be possible to replace a broken pawl spring.

 

[Rappey]

It’s still possible to do a reasonable servicing job without undoing them, i

They really need changing . I would have thougnt that leaving them this time around would make it nearly impossible to remove next time as they corrode further ?
What could happen if they snapped under load ?

 

[Neeves]

However difficult they are to remove now - they will only get worse. The bolts, even the correct ones, cost peanuts - if the bolts fail you may lose the winch (and they don't cost peanuts) or hit a crew member.

Bite the bullet and prioritise their removal and replacement.

If you ask, here, you will get some sensible answers on how best to remove the fasteners (but you might need to start a new thread).

Jonathan

 

[TheBomber]

Do not fear - I will be attempting to remove and replace all of them. Even if there was zero purpose in it, just having such rustiness onboard would irritate me.

 

[littledancersadhu]

I would use a correctly fitting impact driver for these screws, i made this mistake,and had a night mare!