Excellent description ronmar, I did use two pcs of solder on the piston out to the edges over the wrist pin. There was a small difference (3 or 4 thou.) that I was going to ignore, but it sounds quite easy to slip a half shim in there. I'll be on that tomorrow.
Thanks, Steve
I have been reading along here trying to decide if to keep my trap shut or speak on the matter.
Truth is, Nobody on this side of a computer screen can honestly say if .004 is good enough or not on any particular engine. It is entirely possible,, no actually it is probable that shimming the squish to exactly even would NOT be the thing to do. How is that??? Because the machine work on your Indian engine only looks flat, and it only looks square. The facts are block isn't machined square, the crankcase isn't either. The head gasket only looks like it is flat meaning the same thickness all the way across. I have never seen a head that had a flat deck as shipped from India and after it has been torqued down they move around even more. I have never measured a used head gasket that was closer than .004 from being flat. Have you had the rod checked?? bet ya it isn't straight. What about the wrist pin bushing? was it installed and sized correctly? likely not. How many have ever bolted a cylinder head down on a known flat plate using the gasket intended for use and squashed some lead to see how even things are? This test can give a difference of .010 from side A to side B and the plan is to fix it by cocking the base around with half gaskets around so the assembled clearance distance is the same?? Jig or no before you shim the block around try changing over to a spare gasket and check again, the toatl distance will change as will the difference side to side. The GTG gaskets are much better in this respect. The pistons are usually right on and a person can take them out of the equation. The prim and proper route would be to re-machine the entire engine to tolerances that allow you to use .00?? whatever for your squish tolerance side to side. BUT as received from India trying for a .001 side to side squish is like applying rocket science to a rock boat, it dont work.
So what does a person do?
Think about it. If your parts are new or not worn the piston has .006-.010 clearance to the cylinder wall. I have already stated that the pistons are usually dependable, measure your pin heights if you have doubts. And you are going to use the wrist pin as a lever to cock it around in the bore and correct all the other problems??
Only the worst of the worst engines need things like half gaskets under the cylinder and you do not determine that need by measuring squish. What you do is assemble the short block without the head or piston rings or gaskets under the block. Spacers for the head bolts can be anything from hardwood to washers. it doesn't need torqued just snug so it doesn't move. While rotating the crankshaft I watch the rod for side to side movement. this requires a mirror and some patience. I usually do this prior to installing the cam or ider. If the rod doesn't go back and forth on the wrist pin then you should NOT be using half gaskets period. In lieu of remachining the block and crankcase half gaskets can be used to correct errors that cause the rod to move side to side as the piston travels up and down ONLY. Because of the other things mentioned above squish distance will very likely vary from side to side. Average it from side to side to come up with a figure. .040 one side and .050 the other would be .045. etc.
Hope this helps some of ya'll out,
Butch