Topic: soda blasting head

[MasterChief750]

cleaning up an old motor while it is apart is soda blasting the head alright. im more or less speaking of valve guides and seats. its a 750 so the cam towers are out

[fastbroshi]

  Why would you blast a guide?  And the seat I would think not, as that wouldn't help it's sealing properties.  If they're sealing fine I don't see why you 'd do anything.  If anything, a recut of the seat and new valves.   Those old seats are pretty hardy anyway, they take a lot of abuse.  In my experience the rings go before the valves. 

  Is that an F or K motor?

[rbmgf7]

I'm assuming so you can clean the chamber and the safety concern if you were to hit the seats/guides with the blaster?

It should be fine. Soda is the least abrasive media. Don't sit on an area but just enough to scrape the carbon out of the chamber. Be sure to lap the valves once you're done. If you can, try and plug the guides since it's not neccessary to be blasting down them anyways.

[MCRider]

cleaning up an old motor while it is apart is soda blasting the head alright. im more or less speaking of valve guides and seats. its a 750 so the cam towers are out

You gotta figure they are glass/plastic beaded all the time, so soda won't hurt anything. valves seats, guides, pistons, the works.  Soda is a lot more benign and water clean up.

Gotta do a valve job anyway, either cutting or lapping the seats. So glass/plastic or soda, take your pick.

[faux fiddy]

  Soda is a lot more benign and water clean up.

Gotta do a valve job anyway, either cutting or lapping the seats. So glass/plastic or soda, take your pick.

Walnut shells, less abrasive, larger pieces than sand/glass/media blasting so easier cleanup, remains on parts are easier to clean up, softer materials cause less damage than sand if residue remains and finds its way into moving or mating  surfaces.

[MasterChief750]

yeah wasnt trying to say i was soely blasting them. just wanted to double check to see if i should mas them off or just be careful around them. i asked about guides as i would like to clean out exhaust ports. thanks all sorry for slow response busy with xmas

[dave500]

just be carefull around gasket areas and valve seats etc,heres a head i just silica sand blasted,,keep off the gasket surfaces,i didnt even use a wire wheel in the sooty old exhausts,slightly damp sand works well,,off course you have to wash it out bloody well and air blow it then wash it out then air blow it then wash it off and air blow it again,i have a small pressure washer for that,i even blew the sand straight down the valve openings but kept off the seats directly,i get a 25 litre pail from the local garden supply for five dollars,i used about third of it doing this,and top dress my lawn at the same time!it leaves a good surface for paint.

           these combustion chambers were well caked,dont hover in the same spot move on once the soot dissapears.

       the crud in these ports didnt stand a chance,i spent a bit over half an hour on the whole head,it was filthy.