Part Selection for Rebuild

Thank you for the suggestions. I already have plans to get the block deck surfaced. The valve seat area is also concerning (pitted) and I may need to put in seats (which aren't currently there). Surprisingly there are still honing marks in all cylinders from the last time it was rebuilt.

I also noticed this making on the crank (M&T 020). Does this mean the mains are undersized .020?
 

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M&T 020 could be saying that the M (main bearings) are 0.020 undersize but the "T" is a puzzle. Your answer is easily answered by measuring them.
 
Phil Brown said:
Main's and throws both .020
Click to expand...
I agree especially since that's stamped on the crank, not the block, but you'll want to mic them anyhow to check for taper and ovality. Typically on blocks I've seen stampings for C (cylinder), M (main) and R (rods), but T for throw certainly makes sense.
 
Go ahead and deck the block, surface the head or put on a Snyders or Burtz head for a little more poop. Check the valves. Does it have mushroom bottom valves or straight stem valves? If the bores look good check the piston to wall clearance you want a minimum of .0035, .004 is better and out to .006 is ok. Then hone it with a ridgid hone and put new piston rings in. Looks like some stuff went thru the motor and got the crank a little. Just polish the crank and check the bearing clearance. If you need new pistons I wold go with the AER pistons. (Antique Engine Rebuilding) they use a more modern narrow ring than the snyders and they are cheaper than the EGGE's. Open up your oil pump and see if any of the crap went thru it also.
Use the BEST graphite gasket. When your checking the block for straight on the intake/exhaust side of the block you should also check your intake and exhaust manifolds.
They should be surfaced together to get a good seal, maybe thats where one of your issues is. What type of cam gear is on it? I'm sure the engine shop is also aware of all the above, but at least I've given you a few things to talk to them about.
 
did each bearing cap have shims. in other words can you remove any shims to set the clearances.

if so you should be able to just polish the crank. and save the babbit.
 
To answer the questions yes both the mains and rods had shims (two and one shim, respectively). My block will need aggressive decking on the side, it's out .005" and it has moderate pitting that goes in at least .010" more. I will give you an update when I start measuring clearences and will talk to the machine shop when I get the engine down there.
 
Ask your local clubs - Lots of decent running engines floating around from people who installed Burtz engines. Usually $500-1,000.
 
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