Long overdue, 304 rebuild.

Gearhead

Gearhead

Member
1969, 800A Aristocrat with a 304. Six out of eight cylinders measured .006” to 0065”on the wall taper and .0025” out of round. The block is at the machine shop and will be bored to .030” over. I did not measure cam lift during dis-assembly as I planned on replacing anyway. I’m looking at the Insky 256 super cam. Will this cam replace the original (direct fit)? How about the push rods and springs? I would appreciate any info and experience related to the cam fit.
 
Whatever you do, before you do machine work of any kind. Locate all your parts before you do the work.

Pistons have become very very hard to get.
 
I spoke with the Machine shop about the parts. They felt comfortable that they could get pistons .030” over. They did check on .020” over and said they couldn’t get that dimension.
 
I'd have them secure the pistons so they can mic them and have them in stock, before any machine work is done to the block.
 
No machine shop I have ever run across will bore a block without the pistons, unless you give them a finished bore diameter.
The later I do regularly so I can control clearance without the machine shop making decisions for me, but I seldom do stock builds.
 
I agree with you. Unless they have the piston I’m sure they won’t bore the block until they do. They are currently working on the heads. 12 bad valves and all the guides. Both heads need surface grinding. They are looking at the seats. This is an E block so they are saying, “they can cut the seats” as they are already hardened. I need to follow up on that in the Service Manual. Any knowledge regarding that topic would be very helpful. Thank you for your Suggestions.
 
After all this time!! The Machine shop did the work needed. Re-decked the block, bored the cylinders .030 over and did the head and valve work and installed the cam bearings. I am in the process of assembling the engine right now. The cam is in, to spec and the crank is in, to spec. I have set the end play on both so the timing gears are also installed.

I installed the pistons and rod bearings. The rod bearings are (std). The rod direction is correct. The widest spot on the crank is 2.3729.

I have torqued all the caps, loosened and re-torqued. The problem I’m having is the Crank Shaft locks up after I re-torque the #1 rod journal. I have checked the rod bearing clearance. It is in the tolerance. What am I missing?
 
Yes. The Machine shop measured when the machine work was completed. I also measured the journals and bearing clearance during assembly the first time. I removed the #1 piston today and re-measured with a bore gauge. I am used to snap gauges and don’t have a lot of experience with a bore gauge. I checked myself with both and #1 journal bearings look in spec. Pulled out #3 and did the same thing. Not in spec. So I pulled the bearings and looked at sizing marked on the bearing. .010 under. So I pulled all the pistons and inspected all the bearings. Three of the bearing half's are marked .010. Since I purchased a master kit, I called the machine shop and talked with them and also got on Mahle’s web site. The .010 under bearings where packaged under the wrong stock number and I should have paid better attention during install. I would have seen the sizing difference. Problem solved.
 
You must log in or register to reply here.
Back
Top