How much engine corrosion is too much?

[PMBTO]

I recently purchased a small runabout with a 2003 Suzuki DT 30 forward control outboard on it. When I originally inspected motor it looked like new. After closer inspection (now) saw some paint bubbling on cylinder head. Scratched a little and paint came off as seen with photos below. This area is adjacent to the breathing area of the cowl and I guess salt spray has gotten in to the engine in this area. Looking around that end of the engine I can see more areas of salt crystallisation and more paint bubbling. Immediately in front of this area and the remainder of the engine look like new.
My questions are:
- Is this cause for concern?
- What can I do for this now?
- What can I do to stop it in the future.

Thanks in advance for your advice!

[BM]

It looks like most of that corrosion has probably been caused by salt seepage from your head gasket. This is completely normal in a saltwater environment. Salt seepage will always occur from the head gasket.

In this case it looks like the seepage has also caused salt to get under other painted areas and lift them also.

You could scrape off the flakey paint and give the area a wire brush or sand. If you are anal about it you could spray a bit of primer over the surface and then some factory touch up paint. Or just spray the paint straight on the metal as its going to occur again in the future......

Welcome to the most corrosive environment short of an ocean full of acid..... :)

Cheers

[Spaniard_King]

PMBTO,

You are going to get some people saying its serious but really its not. I have seen a lot worse than this on a newer engine as well.

Firstly you need to ensure that all of the anodes are working corectly!

You need to asess if there is any stray electrical currents on your boat (all electrical equipment earthed properly.

If all is good I would be looking at adding possibly 1 or 2 more anodes.. big ones

Clean and protect those areas with a liquid protectant such as lanolin.

Cheers

Garry

[Roughasguts]

Yup salt water sepage, from your head gaskett.

Get some hot water and wash it off, then after dried out, buy some penetrol, made by floods in a spray can, spray that on it's clear and 30 times or something penetrates better than water. Wait till dry 3 days or so, longer the better then paint her black again.

After several weeks spray the motor again with the penetrol, seems to last years on the inside of my motor, don't last long on the leg though.

You can get penetrol at BBC or mitre 10 the stuffs been around nearly 70 years.

[PMBTO]

Thanks guys, I really appreciate the advice.

Garry, is checking for stray current and fitting anodes easy to do?

[snelly1971]

Once you have cleaned it up... spray the motor with Lanolin every couple of trips...Lanolin doesnt come off like other products...

Cheers Mick

[Spaniard_King]

PMTBO,

Stray currents are all about checking that there is no voltage flowing through the hull/engine back to the source/battery

Looking at your pics I am unsure if you have a battery setup or not. If you have, it could be as little as improoving the earth between the battery and the engine or you may have to add an earth between the two.

Stray earths are generally an accesory which uses the hull to earth rather than having an earth wire running back to the negative on a battery

garry

[Roughasguts]

PMBTO, do you disconect your battery after use.
Think it pays to, cause there will always be some leakage with stray current going through switches and the like.

[PMBTO]

Next job beyond cleaning the engine up will be placement of an isolator switch!

Thanks again for the advice.

[Roughasguts]

I just disconect me battery.
Then before I go out for the next trip, I charge the battery and clean the terminals and battery posts. Half the jobs already done then.

But I don't go out very often, pretty sad really.

[OPTI]

You Dont See 4 Year Old Mercurys Doing That.i Guess Thats Why They Call Suzukis Disprens,they Dissolve In Water?:(

[Roughasguts]

You Dont See 4 Year Old Mercurys Doing That.i Guess Thats Why They Call Suzukis Disprens,they Dissolve In Water?:(

That ain't rust Opti, that's the crap paint preperation and it peeling off.

[OPTI]

Well Good Luck Getting The Head Bolts Out.;)