Question on POR 15

[twarren]

I’m restoring a 30-year-old KTM dirt bike and find the magnesium clutch cover/water pump cavity is very badly corroded. It’s still usable but I would like to coat the inner surfaces to prevent further deterioration.

Would POR15 work for this? Heat and anti freeze are the elements to affect the paint.

Or, can someone suggest a better ingredient which can be applied like paint?

Ideas??

Thanks,
Twarren..

 

[Kaizen]

Ive never seen por used internally like that. I’d leave it alone till it fails


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[amolaver]

Admittedly no experience with the idea, but is be concerned ANY of the coating might flake off and plug or limit flow in a small gallery. That interior is not pretty - is the sealing surface really not going to leak?

 

[1926Speedster]

I wouldn't trust POR 15 internally. I would recommend Glyptol, the reddish paint you've seen inside race engones.

Andy

 

[Bigblue&Goldie]

Por15 ***** for its intended application; not a chance in hell I'd use it on that.

 

[twarren]

Glyptol! I have never heard of this before but from what I have read this morning I believe this is exactly what I want. I have even found it locally in Canada at the same price as the US.
I am constantly amazed at what I can learn here at Garage Journal. Thank you 1926speedster.
Twarren.........

 

[Strouty]

It is true, the GJ teaches me more things, of course that generally comes with a lighter wallet too.

 

[Capt Chrysler]

Por15 ***** for its intended application; not a chance in hell I'd use it on that.

My only comment to this.

 

[ng8264723]

Epoxy primer?

 

[metlmunchr]

I'd check with the manufacturer of Glyptal before using it on magnesium. Mag is so highly reactive that the paint may turn loose regardless of how it bonds to cast iron or aluminum. The classic coating for mag is Dow 7 to stop corrosion. The sorta goldish color on true magnesium wheels from the 50's and 60's is Dow 7. Google Dow 7 for magnesium and you'll find a lot of info.

 

[EdT]

I don't know what the impeller looks like, but, generally, water pumps are pretty "loose" AFA the impeller to housing clearance. If that's the case with this one, you might be able to bore out the corroded area and sleeve the cavity with a brass or aluminum part pressed or epoxied in like they do to repair brake calipers. Aluminum might be a good choice since it's close to magnesium on the electro-motive series and galvanic corrosion would be less of an issue. Magnesium would be great, but a bit harder to find. While the part is set up for boring, you might be able to clean up the sealing surface a bit as well. As suggested above, I'd be leery of any kind of coating or filler on that material since it might come loose and plug something up (if all the passages are not already plugged up).

 

[twarren]

Hmm, I thought this thread was dead but not so.
Here is an update. Following the advice of a local engine builder I sand blasted and then applied a couple thin coats of JB Weld. This filled all of the cavities and left a somewhat smooth surface. Then some careful grinding with a dremel and the impeller spins free. Finally a thin coat of VHT paint and I think the thing is going to work.
Thanks for the suggestions everyone.
Twarren.......