Topic: Sandcast #97 restoration

[markb]

You could try and stick it in the oven and drop the liners out, giving you the benefit of not having to work around them and all that heat should soften up that gasket. 

Sorry, but that seems a little radical to me.  I think I'll experiment with ways to soften the gasket.  Thanks for all the great input.

[754]

  BEADBLASTING CASKET Surface before installing gaskets, increses grip...I would do it to the base gasket on a bigbore motor..

[ekpent]

Some good quality liquid,not paste paint stripper carfully applied to the gasket may soften and break the bond. I have not seen much that can stand up to that material.

[markb]

Some good quality liquid,not paste paint stripper carfully applied to the gasket may soften and break the bond. I have not seen much that can stand up to that material.

I dropped it off at a local engine rebuilder to soak in their hot tank.  It that doesn't do it, the paint stripper is my next shot.

[markb]

I got the gasket off.  What a PITA.   


I had dropped it off on Thursday but they didn’t get it into the tank until yesterday morning.  They soaked it all day then scraped on it then soaked it all night and scraped on it again this morning.  Then they put it back in back in for the morning and scraped it one more time before I picked it up at noon.  They got maybe 50% off but there were a couple of scratches bigger than I liked so I decided to tackle the rest myself.  For $35 I was hoping they would be able to get more off than that.  I used some Permatex Gasket Remover and that seemed to help some.  I put it on and would let it soak for 15 minutes on one half while I worked on the other half and back and forth until I got it off.  It was a matter of shaving it off little by little rather than scraping.

I had to grind down one of my scrapers so it would fit between the number 1 and 2 and between the number 3 and 4 sleeves. 


I was tempted to try paint remover but I was at least making slow progress so I stuck with it.  I guess the only liquid that really worked was elbow grease.  It actually looks pretty good.  I don’t think they scratched it that bad.  It was still about six hours of labor total.  I’m glad that project is done.

[MCRider]

Did you ever use any heat? Not saying that it would have helped. I've never used it either and was wondering if it would help.

[sandcastcb750]

The green dots are on the sandcast engine cases and the outside of the #4 carb body. It's a sticker. You can find very similar ones at an office supply store.

Early diecast KOs had them too.

[markb]

Did you ever use any heat? Not saying that it would have helped. I've never used it either and was wondering if it would help.

Good question, actually I did.  I used a propane torch near the gasket and even right on the gasket.  It didn't seem to help loosen it and it didn't even seem to want to burn but I only held the flame on the gasket for a minute or so.

[MCRider]

Did you ever use any heat? Not saying that it would have helped. I've never used it either and was wondering if it would help.

Good question, actually I did.  I used a propane torch near the gasket and even right on the gasket.  It didn't seem to help loosen it and it didn't even seem to want to burn but I only held the flame on the gasket for a minute or so.

That was a stuck gasket. Always a PITA.  Had someone been in the engine before and used an adhesive on the gasket? I don't think they're that tough from the factory.

[y2kc0wb0y]

Like pealing wallpaper. That gasket has probably seen more heatcycles than my Mom's dryer.

[markb]

That was a stuck gasket. Always a PITA.  Had someone been in the engine before and used an adhesive on the gasket? I don't think they're that tough from the factory.

This isn't the cylinder from E100 by the way.  That one has broken fins and bored out to 1mm over.  This one came from E1789 and unless someone did a really good job it didn't appear to have ever been torn down.  Funny part is the cylinder separted from the case easily and didn't leave any behind on the case.

[markb]

The green dots are on the sandcast engine cases and the outside of the #4 carb body. It's a sticker. You can find very similar ones at an office supply store.

Early diecast KOs had them too.

This subject goes a ways back.  Some were red too.  Do you know anything about the significance of them?  My early diecast didn't have one but they might have come off before I bought it in 1975.

[MCRider]

That was a stuck gasket. Always a PITA.  Had someone been in the engine before and used an adhesive on the gasket? I don't think they're that tough from the factory.

This isn't the cylinder from E100 by the way.  That one has broken fins and bored out to 1mm over.  This one came from E1789 and unless someone did a really good job it didn't appear to have ever been torn down.  Funny part is the cylinder separted from the case easily and didn't leave any behind on the case.

Well you got me. All you can do is worry it off. 

[754]

 Along time ago, a tech told me this;
 Use a boxcutter type knife to CUT OFF as much of the gasket as you can. By varying angle of blade, it usually will not dig into the metal and shaves most suff off with a lot less scraping... try it works verey well..

[Old Scrambler]

I had a similar base gasket removal problem......twice on the same motor...........cleaned and replaced the base gasket on a rebuild..........ran the motor for about 5k miles over 3 years.............pulled the head because of a bad valve and did a re-hone just because............another couple of hours with brake-cleaner and a scrapper...........but on the cases..............hard to keep pieces out of the crank...........I used a towel with holes cut for the pistons..........then vacuumed before removing the towel.

[markb]

Along time ago, a tech told me this;
 Use a boxcutter type knife to CUT OFF as much of the gasket as you can. By varying angle of blade, it usually will not dig into the metal and shaves most suff off with a lot less scraping... try it works verey well..

I did try that for a bit at first.  I guess I was looking for something quicker.  Anything might have been quicker that what I did.     Next time I have one like this I'll try that and stick with it a little longer.  Thanks for the tip.

[supersports400]

Hi,

A little late, but with this tool I can remove gaskets, even from pre 1970 Honda's (http://forums.sohc4.net/index.php?topic=65233.25)
The tip angle isn't sharp, but a little sphere, so it cannot dig into the soft aluminum. I also tried to make a copper tool, but this was too soft, and I had to re-cut the tip too often. Like mentioned earlier, older bikes (pre 1970 Honda's) tend to have these stubborn gaskets. Not only the cylinder bottom gasket can be a pain, also the clutch cover gasket. I wonder what kind of "glue" they used in those days

Jensen

[markb]

I haven’t posted lately but I have been busy with the holidays.  Even then I’ve managed to get a few things done.  Besides sorting through my parts for plating I got the cases, cylinders and head ready for painting.  Everything checked out OK on the head and the valves are lapped.  The cylinder is honed and ready to go.  Everything has been blasted, cleaned and masked.  I dropped them off at my painter’s last night and I should be able to pick them up tomorrow.

[Greggo]

Nice touch with the tennis ball 

[markb]

The tennis ball works great for plugging the hole.  I mask the bore first and then push in the tennis ball.  They also work great for plugging exhaust ports.  I haven’t found any other plug that fits very well.  It takes a little cutting but it seals them up perfect.

[markb]

Here are the finished products ready to assemble.
The cylinders:


I did put the head together before painting so I didn’t have to worry about dinging it up with the valve spring compressor.


Lower case:


Upper case:


Gotta love that number


Normally I’d be tempted to start putting things back together but I’m going to work on getting all the parts ready first.  I’ve got some smaller engine parts to paint too but at least I have the big stuff done.

[Magpie]

Gorgeous!! Cliff.

[markb]

Thanks, Cliff.

I decided to tackle the wheels next.  I figured while I was at it I would do the plating for #97 and #1553 at the same time so I’ve got both sets of wheels to work on.


It only took about two hours. 


One weird thing is a lot of the spokes were sticking out beyond the nipples on the 97’s rear wheel.  The other three seemed normal.  Now that I think about it maybe those spokes seemed a little tighter.  I checked both wheels and they’re exactly the same size as near as I can tell.

The rear rims are definitely the rolled rim type...:


… with the DID logo, the only marking on the rim.


I did notice one difference between the rims.  The rim on the right is off #1553 and appears to have some kind of coating in the center of the rim and 97’s doesn’t.  Any significance to that?

[754]

 Your cylinder is not finished, needs the rubbabuggababeebumpers installed.. try soapy water..

 I seen that coating on the rims before.. can you measure rim width for rear, think I  have one in my stash with a slight bump.. be worth trying to fix if its correct for KO..

[markb]

Good eye!  I assume you're talking about the rubber inserts that go between the fins.  They go on the head too.  I have a set of 34 brand new ones just waiting to get put in. 

The width of the rear rim is about 3.160".