Starter motor bendix

[Guest]

Anybody got any thoughts on why a starter bendix mechanism should continually become rusted. The result of this ruined one starter and now the replacement has the same problem. The rust obviously causes the bendix to become inoperable and after a period as short as two weeks the starter has to be removed for cleaning.

I have always worked on the assumption that there should be no lubrication on the bendix to allow for easy travel, however, since the problem started some six months ago I have tried all sorts of lubrication to prevent the rust forming. I am currently using a waterproof grease and hope that I can get better than two weeks.

Has anybody got any ideas - the engine is petrol in a wooden boat with a small amount of bilge water - I am assuming condensation is the cause.

Any suggestions gratefully received.

PZ

 

[steve_cronin]

Yes a bendix should be kept clean BUt it also requires lubrication.

When we ran a fleet of vehicles (motor school) in the 70's the dreaded bendix was a constant source of noise & failure UNLESS they were kept lubricated. Thick oils and grease are a mistake. You should use thin oil otherwise the bendix doesn't respond quickly enough to the initial acceleration so doesn't mesh fully with the ring gear thereby promoting early failure and uneven tooth wear. I would recommend a thin oil with an additive like molybdenum disulphide (Molyslip) or maybe, now that it is readily available, something with P.T.F.E. like "Slick 50". You don't need much, just a thin film but a bendix left dry in the marine environment will certainly rust and rust quickly. Pre-engaged starters are of course superior in marine applications.

Steve Cronin

 

[Trevethan]

Its odd that is it rusting. my starter sits in the bottom of a very damp boat and looks like it did when I replaced it about three months back. The engine has only been started a few times.

Is the corrosion being caused by your touching it? Its amazing what the acid and oils in your fingers can do to steel.

Before I put my starter back in I cleaned the exposed steel with petrol, then wore surgical gloves while re-fitting (more to keep my hands cleanish than anything else!)

I too was told no grease. Maybe try painting it with diesel?

I'd suggest your best bet is to try and get some air moving through the engine space.

I was recently sent a brochure by a company that makes a humidity controlled air circulator. It seems likea very good idea. You sit an air pump in the bilges and when humiditty gets high, on it goes and pumps the damp air in the bilges overboard, to be replaced with fresher air from the cabin, which in turn is replaced by really fresh air from outside.

Its uses minimal power and a small solar panel would be enough to maintain power drain from yiour batteries. Cost is fairly reasonable too... considering its "marine" equipment... somewhere between £200 and £400 I think.

I am quite tempted to give it a go. Combined with a couple of solar powered hatch vent fan thingies, I can see this being a really good way to keep the boat fresh.. and swmbo from whingeing about "the smell of old boat"... course I happen to like the smell of old boat but....

The company's webpage is something along the lines of dryerboats.com or similar.


Regards,

Nick

 

[Aja]

Aha! We had this problem years ago with my fathers' wooden boat before we fitted an automatic bilge pump. Took us ages - and a couple of replacement (Volvo) starter motors before the penny dropped.

Basically if the boat is left for a while and the bilges wern't pumped before the engine was started the level of water in the bilges was just touching the bottom of the fly wheel (an MD2B). When the engine was started and then running, the flywheel collected water at the bottom and I guess the centrifugal effect whipped it round the flywheel, soaking the starter. This could go on for a while until someone decided to check/pump the bilges.

We sorted it by always pumping the bilges prior to starting the engine. For us... problem solved.

Hope this helps

Donald

 

[mtb]

Why not drill a hole quite near to it then using a wd40 type spray at the end of each trip squirt a bit in

http://homepage.ntlworld.com/boats
I want a big steel ex trawler / tug v / cheap or swap for tug

 

[aztec]

bollox, grease the thing, moly disulphide is best.

there was a load more info but i deleted it 'cos i'm gonna get torn up for it!!

regards, steve.

ahh say what you like.... what's done is done!

http://homepage.ntlworld.com/s.amos/index.html