Dissolving Magensium Scale

[vmx1963]

G'day POGGERS!

After a year's layoff due to ill health (long story) I'm finally starting the restoration job on a '74 400 that emigrated from a back yard in Texas all the way to Western Australia

Splitting the cases has revealed the usual KTM magnesium rot, with the added bonus of the crank looking like something from a science experiment. The crank, shaft and bearings all look fine except for the thick layer of mag scale.

In the hope of avoiding the hours of elbow-grease to manually remove the crud, is there a magic chemical that can dissolve the white scale?

Cheers & thanks,

VMX1963
//www.vmxktm.net

[hrbay]

Reversing the "white magcrud" would be nice but would require a degree in chemistry and some expensive reverse osmosis type equipment. Elbow grease and penetrant soaks are my method of choice... The damaged (corroded) cases can be repaired after dissassembly with a suitable epoxy resin or something previously mentioned here but can't recall the name. Let the fun begin.

GC

[farmer58za]

Devcon F

Regards

David
'75 KTM GS250
'75 KTM GS400

[farmer58za]

Devcon F is the repair epoxy

Regards

David
'75 KTM GS250
'75 KTM GS400

[hrbay]

VMX,
     Try a search, "Red Glyptol"... don't know what it is but sounds like the solution to sealing up cases like yours.

GC

[Rain Man]

glass bead blaster

Raymond
 Down East Pentons

[DKWRACER]

"let the fun begin" ? The restoration of a water logged engine has happened before. Of note, if you have dismantled the cases and have the crank assly intact, perhaps, as mentioned, soaking in a bath of diesel fuel, from an earlier post. My fear, is of the connecting rod lower bearing......Once cleaned, carefull examination of the bearing and mains may yield pitted surfaces, if so, deep dudu.. The lower end may have some wobble as well, due to the corrosive action on the surfaces to bear. Once you determine the crank is in reasonable condition, then becomes the task of magnesium restoration.
As mentioned, Kip Kern does have some very good techniques re: restoring the web area, and it does involve media blasting with epoxy application and Red Glyptol, but before getting way out on a limb, you should consider the condition of the core elements within.

Not a real expert, but I do pay attention to what is salvageable.
I am in tears, everytime I pull a motor apart, and the previous owner said " well it used to run, but I let is set outside"


BUT, it is a Penton, and worthy of the effort!

Good Luck, from the "upper fidy" [^]
Tom Brosius
Mile High Pentons

[vmx1963]

Thanks for all the ideas fellas - I remember using devcon years ago in grinding mills (I'm a miner) and the stuff goes like steel, so I'll be hunting around for some plus the Gyptol.

I'll post a photo of one of the cases that I've "de-rotted" - it will make you cry

VMX1963
//www.vmxktm.net

[doncw]

I agree with all the previous advice. After the cases are cleaned and repaired with the devcon the Glyptal is an electric motor paint that should be available in spray can. i am now using it to coat all the interior surfaces and that will end all chance of future rot. used to paint race car engines inside with the stuff to drain the oil back faster. Cheers Don

After a year's layoff due to ill health (long story) I'm finally starting the restoration job on a '74 400 that emigrated from a back yard in Texas all the way to Western Australia

Splitting the cases has revealed the usual KTM magnesium rot, with the added bonus of the crank looking like something from a science experiment. The crank, shaft and bearings all look fine except for the thick layer of mag scale.

In the hope of avoiding the hours of elbow-grease to manually remove the crud, is there a magic chemical that can dissolve the white scale?

Cheers & thanks,

VMX1963
//www.vmxktm.net
[/quote]

[DKWRACER]

doncw, would you be D. Galloway? Owner of a KRP Flatracker? an original, with contributions from BAUB too? [}:)]
Tom Brosius