Magnesium water pump housing repairs?

[PEZBerq]

I am restoring my first water cooled Husky and would like some learned advice from forum members who are versed in the ways of the magnesium water pump casing  .  What should I do (if anything ) with my magnesium clutch covers corrosion at the water pump. The photos show each side of the water pump. The corrosion does not seem to have penetrated the cover ...yet. It looks like a previous owner has applied some resin material to the back of the casing in the pump area. Apart from this pitting the cover is perfect and I am loath to replace it or attempt any weld repairs. The bike is a 87 Husky 510 TE and has a magnesium barrel also - with has some water gallery corrosion also but nothing that will cause me grief during my likely usage of the bike.

I dont know if it leaks or if the seal leaks - I'll find out when I first run the bike I guess 

As it will be used occasionally for pre 90 VMX/Vinduro and stored with coolant drained out (best idea  ) I am leaning towards simply leaving everything as it is. What do people think of this strategy?  Also what is the best coolant to use in these engines with magnesium components - also assuming it gets drained after every race weekend.

[evo550]

There is a guy in the uk who makes billet alloy covers to replace the old mag ones, but yours doesn't look that bad, might be best to just clean up any corrosion and  coat it with something to prevent any more corrosion. The barrel on the other hand is a whole other ball game.

[Hoony]

do they have mag cast Barells evo?

[mboddy]

There is a guy in the uk who makes billet alloy covers to replace the old mag ones, but yours doesn't look that bad, might be best to just clean up any corrosion and  coat it with something to prevent any more corrosion. The barrel on the other hand is a whole other ball game.

Who is that please.

[evo550]

do they have mag cast Barells evo?

Dunno, pez mentioned it in his first post.

The billet covers where shown on a thread in here somewhere.

[PEZBerq]

I think it is www.hva-factory.com

[HVA61]

hva-factory.com

Check their site , it has been recently updated and is really quite good.

Great people and great parts with prompt delivery , I have  a number of their components , including the engine side covers and they are very functional , fit up great and look quite factory

Be aware that shipping from UK is a little more xxee than it is from the USA.

[PEZBerq]

You do not want a magnesium water cooled barrel. Nothing but trouble - that's why they are always alloy nowdays. Now an air cooled Mag barrel is another thing!

[HVA61]

I agree ,the mag. WC barrels can be a little bit of a problem. We had a number of issues with them in the mid to late 80's.

One good thing with them , is that they readily available in new or used condition.

[Mike52]

Tidy up the corrosion [ with a wire brush ] and paint it with something because it,s not too bad.
I think the type of paint has been mentioned on this forum before  but can't remember where.
I think even enamel would do.

The back is from the factory , they are all like that.

I use Motul coolant in mine and have not had a problem.
I would not drain it out as the air/moisture could cause a problem.
Cheers

[Marc.com]

KTM 350s used to be also brutal for corroding out .... I have had a lot of success with Devcon pump repair putty, it dries hard as glass, you need to lightly blast the area so it can key in.... then press in and smooth out. Its designed to do repair corroded water pump, not cheap but the good stuff.

[Slakewell]

You guys do know that you can weld these cases 

[Rossvickicampbell]

and if you use devcon type materials makes the welding job later (as it doesn't last forever) that much more difficult?

[Mike52]

I have used Devcon on an 86 KTM and the coolant got behind it making the problem worse and hidden.
I thought I had cleaned the base metal all up and was disappointed next time I looked.

This one that Pez has posted a photo of has hardly started and really doesn't need anything done to it.
A coat of paint would settle any worries down tho.

[Marc.com]

I have used Devcon on an 86 KTM and the coolant got behind it making the problem worse and hidden.
I thought I had cleaned the base metal all up and was disappointed next time I looked.

thats why I mentioned the surface preparation has to be spotless, oil old coolant etc and it will not take. Plus you need the pump repair putty not any old Devcon product.