Radiator paint bubbled and flaking on LH side

[atoyot]

Hi,

Now that I've starting pulling bits off the bike, I'm finding a few oddities. One that has me a bit worried is the paint on the LHS of the radiator is bubbling, and scratching it with my fingernail flakes it off. Under the painted surface, once the whitish crusty stuff is brushed off is bare aluminium. No leaks at all, but I suspect that this might be galvanic corrosion. I'm going to rip the radiator out tomorrow and give the whole system a good flush, but probably just take the radiator to a shop for pressure testing.

Anyone else seen this and if so, what did you do to fix it or repaint it? I know that if cooland isn't changed, it actually holds a small voltage, so I think that it might be time to drain it at the very least.

Andrew

[Malcolm6112]

Flush the cooling system with a hose. I found it easier to remove the thermostat first, as mine had seized open, so I was going to change it anyway. You will find an engine drain on the RH side, under the exhaust headers. Then flush it with distilled water. You'll need at least 4 to
6 liters. Tap water normally has a lot of mineral salts. Put the thermostat back in, add coolant. I preferred a quality premixed.
You haven't said how old your STead is?
Are you getting two or three bars on the temp gauge?

 

[atoyot]

Hi Malcolm, yes I'm getting 3 bars on the temp guage. I've got a '03 ST1300, with 26000 k's. I've only had it a month or 2, so I think I'll change all fluids and oils to be sure. My main worry is about the corrosion on the LH side radiator tank,

regards

Andrew

[Brock]

There may have been a scratch in the paint that allowed water to get in, and with time n heat the paint lifted and the surface corroded slightly. Clean the surfaces, re-prime and give a nice new paint job. all should be good for a good while. (Matt Black heat paint is good)

[atoyot]

I've attached a pic of the radiator, and I will drop the coolant, remove the radiator and repaint it.

[Brock]

Definitely exfoliation corosion, Ally is prone to it. A rub back with scotch brite to get back to clean metal is in order, sand paper is to hard on the metal.

[atoyot]

Thanks, Brock. I'll raid the kitchen cupboard for Scotchbrites!