Restoration of Sandcast #97

[markb]

I kind of got distracted with the side stand mount.  That and Christmas coming up and I haven't had a lot of time to work but I have finally have all the parts on the cases off.  Here they are.


My plan now is to degrease and clean them up as best I can.  I found a place to do the hot tank thing but no luck finding someone that can to the ultrasonic but I'm still looking.

[kp]

All coming together well Mark but yes, you need to take a break for Christmas. If you and Wayne need it I could knock up a template and send it over KP

[kp]

Mark, Any chance of you posting a good quality, reasonably close up, picture of your cam carrier assemblies. I keep records of this stuff and will publish it all in coming months. Thanks KP

[markb]

No problem, I'll get some this weekend.
Mark

[markb]

I had little time tonight and didn’t feeling like tearing down on the other sandcast or cleaning the cases so I decided to tackle something easy like removing the rotor from the crank.  I’ve been soaking it in Safest Rust Remover since last week.  This is the stuff.  It works great.  Check it out: http://safestrustremover.com/


I only had a gallon so I put the crank, rotor side down, in a bucket, since last week.  Crappy picture but you get the idea.


Remember that here’s what it looked like before.


So I had the torch ready but decided to put the wrench on the rotor bolt and give it a test twist.  It came right off!   Then I put my special rotor removal tool (20mm hex head bolt) into the rotor and it came right off!!   Here’s what the rotor looks like after the soaking.  It’s not perfectly clean but that was with no brushing, no agitation, no nothing.  All I did was dry it off a little with a rag.


Some more good news, it’s the correct (for this VIN) 10mm bolt.


Here’s the 10mm hole.  The later sandcasts have a 12mm bolt.  Seems like that’s a pretty large increase.


So that went way too easy so I says to myself…(I won’t say it) why don’t I try to remove the spark advancer shaft.  I’ve been soaking it for weeks now.  I double nutted the threads and gave it try.  No go.  Out came the torch.  I heated on it for about 5 minutes.  She was smokin’.  Gave it another try and it came out!!  I’ve always had trouble with these probably because you’re trying to turn a 8mm thread with a 6mm shaft.


  So it was a good night.  Start to finish about ½ hour.  Now I’m really scared.  I’ve had kind of a good, bad, good, bad cycle.  I can’t wait to see what happens next.

[Wayne]

Wow! That stuff is amazing! Not to be cruel but I'm glad it's you Mark. Being my first sandcast I don't think I could handle the additional stress of all that rust! I'm stressing over a broken fin and an exhaust flange bolt broken off even though I know they are easy fixes! You sure so seem to find an answer for each challenge that beast throws at you. 

[Steve Swan]

Mark, Who told you about Safest Rust ?  Did you get Safest Rust off the internet or a local supply store ?  Just wondering if it's a product i could source locally without having to have it shipped in.  Looks like GREAT STUFF !!!!  I gotta have some !

[markb]

I think I learned about the Safest Rust Remover from the SOHC4 forum quite a while ago.  It is some good stuff.  I don't know if it can be bought locally, I bought mine online and I'm going to buy some more soon.

Edit: I just checked online and I remember why I only bought 1 gallon, it's a little pricey at $25/gallon or 4 gallons for $84!  But it works so I'm biting the bullet and getting 4 gallons.

[Steve Swan]

Does the bottle say what is the active ingredient ?

[markb]

I checked the bottle and there's no ingredients listed. 

[Wayne]

I found a place to do the hot tank thing but no luck finding someone that can to the ultrasonic but I'm still looking.

Mark
I was talking with an old builder friend of mine. He advised us to be careful hot tanking aluminum. He said it can be done but the person doing the job must be well versed in cleaning aluminum. You can't use the same bath they use for cast iron pieces.

[markb]

Wayne, thanks for the heads up.  I'll be sure to ask them about doing aluminum.  The place is a local, well known engine rebuilder that's been around for 50 years.  I would assume they get into some aluminum block stuff but I will definately double check.

[Steve Swan]

I know you'll be very careful, Mark.  My only advice would be whatever method you decide to use to clean the cases, would be the least disturbing to the integrity of the aluminum.  The larger issue is making certain the oil galleries are clear.  Seems like ultrasonic cleaning is the method of choice, assuming u.s. cleans inside as well as out.  I've never used it, but i have always heard 2nd hand it's the best.  Conrad's experience with u.s. looks and sounds great.  I use plastic blast media because it has no abrasive left over debris and really does not disturb external surfaces.  The bottom line is you want to use nothing that will alter the surface texture and, heavens forbid, harm or damage the cases.  In that case, talking to people who have first hand experience with cleaning methods is necessary.

[1941wld]

Mark, The safe rust remover is an excellent product. Donzie and I've have gone thru several gallons of concentrate. This product has a life, it does not last forever. it will stop working. Also be very carefull when it get old. It will harm  steel items if they are not completely under the liquid. If an item is half in the liquid and half out there is a deteriorating reaction that takes place along this line as I have viewed while cleaning a gas tank.

[markb]

Again, thanks for the heads-up.  It's nice to be able to learn without making mistakes.  I just bought some fresh Safest Rust Remove so I'm not going to use the older stuff just to be safe.
Also, as far as the hot tank and ultrasonic, I have checked with the engine builder and they do both cast iron and aluminum and they're aware that there are chemicals that are bad for either and assured me that there won't be any issues.  Again, better safe than sorry.