Restoration of Sandcast #97

[markb]

Thanks for the "hot" tip.  I have done that but usually as a last resort.  I always do it when I'm removing studs and never had a problem getting them out.  Good idea just to do it on everything when an engine is this bad.  No down side to everything coming out easier.
Mark 

[kp]

Mark,
Sorry about the post. Looking at your workshop why wouldn't you know to do this. Shouldn't have told you how to suck eggs KP

[Steve Swan]

Working with rusty steel in oxidized aluminum can be nerve wracking.  We've all twisted something off at some point in time or we haven't worked on 'em.  I'm keeping my fingers crossed for the cylinder block removal.  I am infatuated with those exhaust spigots and the cam cover cross hatching !

[markb]

Mark,
Sorry about the post. Looking at your workshop why wouldn't you know to do this. Shouldn't have told you how to suck eggs KP

Don't be sorry!  I may know to do it but the fact was I wasn't doing it and should be.  And because of your post I will be now.  This is certainly the most challenging project I've had so any advice is appreciated.  Especially with everyone watching, I want it to be right.
By the way that's my work's shop.  Just lucky enough to have a little corner I can work on my projects.
Mark

[kp]

Yes indeed Steve, they are amazing finds. And the treasures yet to come 

[Steve Swan]

Well, since Mark's given us permission to beat our drums........    

I LOVE KANO LABS AEROKROIL  !!!!  

I've used it for 30+ years and a dear freind of mine used it since it came out in the 40's.  

I've seen it make "frozen" ancient rusted stud removal look miraculously easy, in cases where the stud would have twisted off.  I've also used it on rusted ancient struds that were twisted off, of course then having to use an EzeOut with heat.  Using AeroKroil, i've never had a "frozen" stud refuse me.

Can be ordered on line - http://www.kanolabs.com/

[markb]

OK, you talked me into it.  I've got some on the way.  I'll weigh in after I've had a chance to check it out.
Mark

[Steve Swan]

Cool !  Let me know what you think !  

When the stud is removed, you can see the AeroKroil has penetrated it's way along the threads.  Usually, i give the part to be removed 1-2- or 3 soaks, depending on how rusted, i will wait anywhere from a couple hours to a few days.  Helps to have some exposed threads.  Where there's no exposed threads, such as in the case of a Phillips or a hex head, it's more difficult for the penetrant to make it's  way in.  In these cases i still use AK, but i give more than one application, apply some heat inbetween applications, after AK's had a chance to penetrate.  Once the object of affection has loosened, depending by feel, before attempting removal, i'll squirt some more AK, then turn back and forth and squirt, and turn, so forth and so on, til the part comes free.  But, where there's a stud going into the object or a nut on a stud, it always does the job.

[markb]

I haven’t had much time this week to work on the bike but in anticipation of trying to free up the engine this weekend I decided to give the cylinders another good soaking.  While I was wiping out the cylinders I noticed a 1.00 stamped on one of the pistons.  Ruh-roh.  A quick check revealed the same thing on the others.  I measured the bore to make sure but yes they are oversize pistons.  I almost had to laugh.  Cylinders 2 & 3 are down and the cylinders don’t look to bad.  Numbers 1 & 4 don’t look so good from what little I can see.  So maybe I’m thinking too far ahead here but assuming the worst and the cylinders are not good what are my options?  Replace the jugs, resleeve and rebore to stock, or go bigger yet (is that possible)?  Either way I replace the pistons.  Keeping in mind a fairly exact restore, is an oversize bore acceptable?  I’d like opinions guys.  One more question, anyone ever split the case, remove the bottom of the connecting rods and pull the cylinder with the pistons in place?
Thanks,
Mark

[hondasan]

Mark,
For me, re-bore during restoration is not an issue. That said , I have never had one at +1mm, therefore requiring non Honda oversize pistons. My personal preference would be to re-sleeve, or replace the jugs to be able to stay within Honda's own range of piston sizes.
Each to his own in this sort of area for me, and after all, when its done, only you have to be satisfied with the result.

If pistons are seized, I ALWAYS do what you suggest - ie, split the cases, undo the bearing caps and reomve the block with pistons / rods attached. At least that way you can deal with the pistons one at a time (and hopefully some of them will be free anyway) rather than risk block damage, bent con rods, etc, going the other way.

Cheers - Chris R.

[Steve Swan]

Before i replaced the cyl.block, i would want to make sure there were no differences between #97's cyl and a later one used of some other sandcast.  That seems the easiest solution and i'm like Chris, i don't see boring to o.s an issue.  

Re-sleeving to std is certainly the option of choice for originality's sake.  

the 3rd option i can think of would be to use an 836 kit...........  That's a pretty radical measure for remedying the problem, especially considering we're talking about #97..........  The power would be really cool and the sound out the LR's would be equally cool, especially if the head was flowed ot match the 836 kit.  I'm having the head flowed on E2241, but nothing else. I actually thought of having the cyls bored to an 836, but hated to do that since they only needed to be taken to 1st o.s.

I've re-sleeved 2 different times, both on single cyl. 500cc engines.  The procedure is not difficult, but how a person is going to remove the sleeve and then drop the new sleeve in, the procedure must be thought out step by step and carried through accordingly.  One does not want to get a sleeve stuck sideways in a bore or not pushed all the way home.

[markb]

Well, things aren't getting much better.  I got the transmission cover off OK but wasn't happy with what was underneath it.  I guess that's what I should expect.


I've got all the screws out on the rotor cover but one.  It's stuck part way out.  I was hoping if I could loosen up the cover I could get some rust loosener down by the threads.  I wonder if this is the hole with the pin.  I soaked all around the gasket edge hoping that will loosen it up.  I've got a funeral to go to now so I'm going to let her soak.

[cb7504]

Mark:
       The hole with the screw still in it, is not the one with the alignment pin. The one with the alignment pin is the forward one of the two screw holes on the bottom of the alternator cover.
       Mark if you can tap the cover away from the cases and apply some oil or light film of grease to the screw shaft and threads if showing. Tap the cover back into place, tighten and un-tighten the screw several times until it comes out. If all else fails remove the screw head and slide cover off and deal with the stud by it's self without possible damage to early thin lipped alternator cover. Marty K. 

[Steve Swan]

I like Marty's suggestion of removing the screw head and removing the cover.  If you don't go that route, then in addition to what Marty suggests, I would also heat the case in the area the screw is threaded into.  And, since you've ordered AeroKroil, i would wait until i had the AeroKroil to squirt on the screw where it goes into the case, after you've separated the cover from the case.  When i have these stubborn screws, if there is room, i will get on them with a ViseGrip, that way there is no back and forth "slop" one would get using a screw driver.  Using a ViseGrip, I can actually feel the screw threads turning in the aluminum, taking care to also watch the entire screw turn, making sure it is not only twisting the exposed area of the screw.  Using a Visegrip makes it easier to feel how much torque to apply to avoid twisting off the screw.  The screw is not going to be useable after you've removed it anyway.   Using a screw driver, it's impossible to feel the screw turn one way or the other.  In addition, it could help to to lightly tap the end of the screw, anything to disturb the debris 'cementing' the steel threads to the aluminum threads, especially, at this point, to turn the screw back in.  Those threads are about a 90% fit, so there's not a lot of room to move the screw in the threads that are full of debris from rust and oxidation.  AeroKroil, heating, tapping and turning the screw back and forth a 16th of a turn with a ViseGrip, repeating the procedure is what would be safest.  Since you were able to turn the screw part way out, it's obvious the screw can be loosened.  The problem now is, in turning the screw out, the debris of rust and oxidation has piled up in the threads of the hole and the screw CANNOT turn out any further.  Attempting to turn the screw out any further, will increase the risk of twisting off.  The screw needs to go back in, at least a lttle bit, before it can come out any further.

Brother....... !  Looks like that engine was sitting in a lake.  

[kp]

Brother....... !  Looks like that engine was sitting in a lake.  

Hey Mark, Steve's right; so it's no good going any further with the project. Can you ship the lot over to me. I'll be happy reluctantly be able to take it off your hands  . Seriously It's exciting following this project KP