Honda bf20 corrosion on engine - advice please in remedy?

[Jung at Heart]

I have picked up a 2011 Honda bf20 which has not had much use and was regularly serviced by a dealer until it was stored for two years.

It appears that it has inadvertently been stored with some sea water left under the cowling and now there is fairly extensive rust on the what appear to be just the external engine parts.

Externally the engine looks fine, it seems just to be the parts around the block that have corroded.

What is the most cost effective way if dealing with this issue please, should I take it in to a dealer to be inspected and have the parts changed or is there something I can do myself that will avoid that course of action.

Also what are the implications for the engine, I think i will be happy to get it sorted and run it for as long as it lasts so Resale in future isn’t a concern but I would like to know if the rust makes it not worth repairing?

Thanks in advance for any suggestions on a sensible way forward.

The pics show a sample of how much corrosion there is.

[Fenlander]

I have to be brutal... I really don't like the look of that. I've had over a dozen used outboards as old as 24yrs at time of ownership and never seen such heavy rust on components. There is no reason for that amount of salt water to be in the under cowl area.

Is there a chance this has been submerged in the past? Does it start and run faultlessly?

If it were mine and I thought there was some weird but innocent reason and it is otherwise OK so decided to keep longer term I'd have to go through it and take those bits off and treat/ paint spray the brackets then replace the rusty headed bolts... but I am a bit OCD about under cowl condition.

Pics below of my Yamaha which is what I'd call average clean and is 8yrs older than your Honda... and a previous Mercury that was about 19yrs old.

The pics aren't to wind you up just to show the typical condition under the cowl of leisure use portable outboards.

[Jung at Heart]

Originally Posted by Fenlander

I have to be brutal... I really don't like the look of that. I've had over a dozen used outboards as old as 24yrs at time of ownership and never seen such heavy rust on components. There is no re

I agree with you Fenlander, all of my outboards in the past have been immaculate for all of the time I've owned them, even the one which gave me nightmares but that was for mechanical reasons and the lack of spares.

The chap that I bought it from is honest, I take him at his word that when he last used it it was immaculate and he is happy to refund me if I'm not happy to keep it. I think it's had sea water in and just been left, there's no sign of corrosion elsewhere that I can see and it doesn't appear to have been cleaned up elsewhere.

I've been looking at the Honda parts diagrams this afternoon and the parts are available to replace the parts that are rusty, I think that is my preferred option rather than cleaning them up.

It's certainly a risk, i will need to give it some more thought.

Thanks for your input, it is very helpful as always.

[Fenlander]

New parts even better.

Have we discussed timing belt and pulley on these motors?

If the under hood atmosphere has been less that ideal I'd change the belt now. Also do you know that model had an issue where the timing pulley boss wore badly (or perhaps the timing pulley itself breaks up... plastic I think) giving excess play throwing the belt off?

That's about all I know to watch out for on that model.

[jeffstevens763@g]

It's been for a swim electrics next

[Jung at Heart]

Originally Posted by jeffstevens763@g

It's been for a swim electrics next

Thanks for taking the time to chip in Jeff.
When you say electrics next, I’m assuming you are saying yet they will corrode and fail is that what you're expecting to happen?

[jeffstevens763@g]

Originally Posted by Jung at Heart

Thanks for taking the time to chip in Jeff.
When you say electrics next, I’m assuming you are saying yet they will corrode and fail is that what you're expecting to happen?

That would be my fear there's a blue tinge on some of the parts could be copper sulphate deposited I might be wrong well hope i am. I certainly would be giving it a liberal coating of moisture repellent and get some q rust on the steel bits after rubbing down OMO

[Jung at Heart]

Thank you for all of the advice on this engine, the chap I bought it from has been very decent about the whole thing and was as surprised as me to see the corrosion and we have agreed a way forward that suits us both.

I've decided to keep the engine and am looking forward to making a start on cleaning it up, over time replacing whatever needs replacing and hopefully to enjoying it for a few years to come.

Now off to order some parts including a timing belt and a camshaft pulley, I understand that 20HP on my new T38 will be very different to my old river cruiser with it's 9.9hp and 6 knot speed limit and i can't wait to try it!

[The Crabbotherer]

Are you going for the Alan Young engineering version of the pulley? I bought a BF20 back in March and have done the belt and pulley, plugs, thermostat, anodes impeller etc etc.
Mine was a little bit corroded around the plated mild steel mounts so have given everything a good blast of ACF50 and all looks nice and glossy now, however it runs fine but then keeps cutting out.
I'd have thought if yours runs fine, a good clean and rinse down then some corrosion treatment and hopefully you'll be ok
best of luck

[Jung at Heart]

Originally Posted by The Crabbotherer

Are you going for the Alan Young engineering version of the pulley? I bought a BF20 back in March and have done the belt and pulley, plugs, thermostat, anodes impeller etc etc.
Mine was a little bit corroded around the plated mild steel mounts so have given everything a good blast of ACF50 and all looks nice and glossy now, however it runs fine but then keeps cutting out.

Thanks for your message.
,You’ve done a fair bit to your outboard, do you know why it’s cutting out? It sounds frustrating after all of that work.

I’m not sure whether to go for the Alan Young version of the pulley or just use the Honda one and keep an eye on it, which pulley did you use and was it straightforward enough to replace?

It certainly looks like the mild steel plates and the bolts are prone to rust, I wonder if it’s just cost that stops Honda using stainless steel.

I have enquired about buying parts to replace some of the rusted items, it seems that my local Honda dealer is very slow at responding if they are going to bother at all.

I’m not sure how well the engine runs at the moment, I’ve tried it on muffs bout not on the boat yet, hopefully it will be fine, I’m going to give the carburettor a good clean as the engine has sat for a while, wondering whether to pick up a cheap ultrasonic cleaner or just use a can of cleaner.

Once it’s sorted I will take it out for a run and report back.

[The Crabbotherer]

I bought the engine just before the apocalypse began so took the opportunity to work through it, i did go for the billet aluminium pulley having read all the horror stories about the plastic version.
Changing it over was pretty straight forward once i'd sourced the right puller.
I guess there's something going on in the carb so will try a good blast of carb cleaner and if that doesn't sort it (i'm not hopeful) i'll turn it over to the professionals and throw some money at it.

if you're anywhere near Boardwise in Cannock i could send the pullers down to there as i've got a mate who travels down weekly if you want to borrow them.

I'd just clean up the various corroded parts as they don't look shot thru and spend your money on the pulley. The various brackets seem to be made of cr@pply plated steel.

i'll post some pics of mine later when i go for the second attack on the carb.

it is possible to remove the wiring harness and give it a good soak in distilled water to remove any possible salt ingress, or better still in a ultrasonic bath?

[Jung at Heart]

Thanks for the offer of the loan of the puller, that will be great, i'm only 45 mins or so from Cannock or I'm happy to pay for insured postage if that works?

Hopefully a carb clean will get yours running reliably. Thanks for the tip on soaking the wiring harness, i will give that a try.

How much was the Aluminium pulley please? I read somewhere £130 but that was an old post.

[The Crabbotherer]

The pulley was 140 quid total delivered
pm me your address and i can post it no problem, it'll save you a 2 hr round trip!
Just beware that the puller only comes with one timing mark, i just marked the 2nd one up with a marker pen to be sure.
i'll sort the pulley out when i'm up at the garage later rather than post the whole box with all sorts of heavy pieces you won't need

[Livid]

i've seen worse, it just looks like the bracketry is rusted. I agree with the others, you should definitely check and clean the electricals as that would lead to a miserable bout of mystery issues if they go on the fritz