Topic: Sandcast #97 restoration

[Greggo]

Another one, huh!?  With the prices still rising, and more n more people looking to sell, it seems to be a good time to be buying.

[Old Scrambler]

Some people say that 3 is a crowd!  Others say its a good hand to draw to! I know of one other sandcast collector with 3 bikes...........so there must be others!

Regarding the brake lines..........I have a lower brake line that I purchased new in the 70s for a potential double-disk set up. Never used it. I don't know if its the same part number, but if you need it give me a holler.

When do we get to see your new addition?

[754]

 I have turned the finned filter can down. It looks good but has no tang.. Will keep you happy for a while..

 I think the originals were weak & broke when overtightened, so a de-finned one may be stronger.. not sure though..

[MoMo]

Mark,   

It is possible that the white dot at one time had the initials of the assembler.  From what I understand some of the early sandcast were hand assembled.  Larry

[markb]

Another one, huh!?  With the prices still rising, and more n more people looking to sell, it seems to be a good time to be buying.

I hope so.

Some people say that 3 is a crowd!  Others say its a good hand to draw to! I know of one other sandcast collector with 3 bikes...........so there must be others!

Regarding the brake lines..........I have a lower brake line that I purchased new in the 70s for a potential double-disk set up. Never used it. I don't know if its the same part number, but if you need it give me a holler.

When do we get to see your new addition?

There are definately others.  If you check the SOOC site there's probably at least fifteen collectors that have 3 or more and one guy has 10!  
The early brake lines had a short-neck banjo and I think were used up to VIN 2157.  I don't think the part number changed.  Can you email a pic?

I have turned the finned filter can down. It looks good but has no tang.. Will keep you happy for a while..

 I think the originals were weak & broke when overtightened, so a de-finned one may be stronger.. not sure though..

I have a turned down oil filter cover too and may have to settle for that.  I agree that they're probably a little stronger because of internal ribbing.

Mark,  

It is possible that the white dot at one time had the initials of the assembler.  From what I understand some of the early sandcast were hand assembled.  Larry

Might be possible.  There's a pretty good discussion about this on the SOOC site.  Here's a link:
http://cb750sandcastonly.com/smf_forum/index.php?topic=383.0

[markb]

I just had a huge surprise.  I knew the bike I picked up had a 2-hole airbox.  I never even looked to see if it had the reliefs because I assumed it wouldn't because it's a later number (1553).  I took it off tonight and it doesn't have reliefs!!  Even better it's in incredible condition.  I was kind of bummed out when I got home from picking it up all the way from New Jersey to Minnesota, because our house had been broken into.  This doesn't make up for that but it helps. 
One thing I need input on.  The center part is stuck to the top.  I didn't try very hard to separate them.  Does anyone have any suggestions for getting them apart without damaging them?
I don't have my camera with me but I will post pics as soon as I do.

[markb]

Here’s pics of the 2-hole, no relief airbox.  I don’t think I’ve ever seen one (any airbox) in this good shape.  Too bad it’s the wrong color.  Minor detail.  By the way it’s much greener than the pics show.


Closeup of the corner with no relief.


I haven’t tried separating the middle from the top yet.


There are a couple of small cracks here but very repairable.


Bottom half.


Doesn’t show up in the pic well but the bottom is slightly warped.

[Magpie]

No pics just the dreaded red "X" or is it just me. Sounds like a good score though Mark.
Cliff.

[markb]

It wasn't you, pic problem solved.

[goaarongo]

Learning a lot from this thread.  Thanks for sharing so much about your project.  If those two pistons are still stuck, you might try this technique for removing them: http://forums.sohc4.net/index.php?topic=70136.0  - I was really happy with the way it worked.

[markb]

I got them out after I disconnected the rods from the crank and pulled the cylinders off with the pistons in place.  Some good soaking from the top and the bottom and they came out pretty easy.  But I've got another stuck one to work on, don't know how bad yet, so I might consider that option.
Thanks,
Mark

[markb]

I hesitated posting this because I figure I might get some “I told you so’s”.  But maybe someone will have some good input so here goes and I know I’m not the first one this has happened to.  I had some time over the weekend so I decided to work on getting the starter motor out and tackle the studs.  I took it slow and worked on the motor for about an hour and finally got it out.  On to the studs.  I already had one out and had been heating and soaking all week.  A couple were a little stubborn so I heated and soaked them and moved on to the next ones.  After about another five hours, everything was going good until I got to #14.  I use a vice grip and if it slips I know the stud is still too tight.  This worked on my last two projects and never had a problem.  This one actually moved about a half a turn and SNAP.  Son of a….


Here’s a close-up.  It broke off about an 1/8” above flush.  That’s the good news.  I’m still thinking about what to do but I think I will make a bushing that’s c’bored on the bottom the diameter of the stud and a smaller hole drilled through the top so I can get a pilot hole exactly on center.  Then drill out the stud using an 8mm x 1.25 tap drill and then pick out the threads.  I’m thinking I might not keep track of my hours anymore.

[Roach Carver]

I would weld a nut to it. the extreme heat usually loosens it up.

[markb]

Hmmm.  I kinda like that idea.

[y2kc0wb0y]

Good read. I have no desire to restore like this but I completely respect the attention to detail and patiences needed to achieve this. I'm happy to have read all your updates until now. Consider me subscribed. The welded nut trick does work.

[markb]

I’m thinking ahead here a little.  Has anyone ever removed item #6 in the drawing below?  I took off the cap (item #5) on the other side (which surprisingly came off quite easy) and it doesn’t look pretty.  I don’t know how that much dirt and sludge could get in there.  Anyway to do a proper job of cleaning out the oil path it seems like removing the plug (item #6) on the other end would be helpful.  My guess is it’s just pressed in.  Once I get the cases stripped down that will be my next job is to thoroughly clean out all off the oil passages.  Some of them are completely plugged with what looks like mud.

[ken736cc]

That plug is a press fit. You can easily remove it with a long dowel pushed in from the other side.

[markb]

Some good news.  My studs are out!  I’m afraid I wussed out on you guys though.  After much good advice I had a shop EDM (Electrical Discharge Machining) them out.  I mentioned my problem to one of the guys in my shop and he suggested I just do that.  Doh!  We occasionally have a tap broke off in an expensive part and we just send it out.  I felt the odds of maintaining the threads was better that way too.  The threads look good and I did a test torque and they went to 8 lb.-ft. no problem.  By the way the oil hole plug came right out.


Now I can move on to this mess.

[myhondas]

Mark,

That looks really bad, but I think you will find that it looks worse than it really is. Most of that will clean right up and leave you with a nice clean case and gears.

[markb]

I tried to pull out the gearshift fork shaft but it wouldn’t budge.  The end of the shaft is tapped with an 8mm thread so I threaded in one of my studs to try to pull it out.  The forks moved freely so I figured the shaft was stuck in the case.  So I drilled a hole in a piece of bar stock and made a slide hammer.  Then it came out easily with a few light taps.


Then I decided to tackle the pin the holds the kick start spindle.  Normally I use a side cutter to pinch on the pin and a thin piece of sheet metal to protect the machined surface on the case and pinch and pivot until it comes out.  Of course the pin gets damaged but I just replace it.  No luck this time.  I’ve been soaking it but being a press fit I’m not sure how much good that does.  I don’t want to try to rotate it because being a spring pin I’m afraid it will damage the hole and I think it’s too hard to try to drill out.  Any ideas besides burning it out?

[754]

Try warming up the case before pulling, the ally case will grow more than the part. The shaft you pulled would come out easier and maintain its fit..

[lone*X]

Looks like a fairly large pin, how about running a small tap inside it and screwing in a hardened screw/bolt.  Would give you the screw head for a better purchase on pulling it.  Or affix the screw to your slide hammer for some light impact. 

[markb]

I think that's what I'm going to try first.  The pins are pretty hard so hopefully I can tap it.. without breaking the tap.  That and soaking and heat and patience and it should come out.  Thanks for all the suggestions.  I'll keep you posted.
Mark

[754]

I think the tap will break, not only hard but interrupted cut as well.
 Can you tack a piece on to fasten to slidehammer.

 When you clamp a vise grip to the slit-pin, will it not close it enough to loose its grip?

[Toxic]

Wow, your persistence and dedication are inspiring.

Carry on.