Crack/Knick in 350 Cylinder Wall

This block sat uncovered last winter and was full of water/antifreeze. I’ve torn it down and noticed this crack or knick in the cylinder wall. What do you guys think? It appears to be a Knick to me because one side is higher than the other. A crack would tend to be somewhat flush with a tiny gap? The pistons were seized in there really bad and took some banging to get out. Is this something honing could fix or is this block trash? Zero engine experience btw

Crrrraack!

Thats now a boat anchor. Thats a crack and needs sleeved but most wont spend that money on a 350.

Magna86 said:

Thats now a boat anchor. Thats a crack and needs sleeved but most wont spend that money on a 350.

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Do I have to sleeve all 8 or just the one that’s cracked? It’s bored .30 over right now so would a machine shop bore it over the thickness of the sleeve so that the .030 pistons will fit or does it get sleeved back down to stock of 4.00” bore?

I wouldn't toss it yet. 350 blocks are scarce. When I worked at PAW in the late 90's, cores were drying up and we started putting in 8 sleeves and making std bore blocks. It was actually a $100 upgrade as the sleeves were substantially stronger and consistent thickness.

SMC2224 said:

Do I have to sleeve all 8 or just the one that’s cracked? It’s bored .30 over right now so would a machine shop bore it over the thickness of the sleeve so that the .030 pistons will fit or does it get sleeved back down to stock of 4.00” bore?

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You'll have to sleeve the one and probably bore the entire block 0.060

Bennyt said:

You'll have to sleeve the one and probably bore the entire block 0.060

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I’m sorry, this doesn’t make a lick of sense to me. If I put a sleeve of let’s say 3/32” or .09375”. The bore is now 4.030 - .09375” = 3.93625” in that cylinder while the rest are still 4.030”. Are you saying bore .060” from there? So 3.93625+.06 = 3.99625”? Or bore all 8 cylinders to 4.060”? Cause if that’s the case wouldn’t that just bore through the crack? Why put a sleeve in there if it’s gonna be bored away? Thoroughly lost how the bore could increase after sleeving? Unless I don’t understand how sleeves work but I was under the impression it just sat in the old cylinder wall

You have to bore the block like .250 and then the sleeve is press fit in. Basically cutting away the old material Then you bore the sleeve to match the existing cylinders. You stated existing is 0.030 but based on what I am seeing, I am going to assume all the cylinders will need to be bored during a rebuild.

And don't worry about sleeves. Substantially stronger than stock, used in diesels. Plenty of matching numbers blocks saved with sleeves.

Bennyt said:

You have to bore the block like .250 and then the sleeve is press fit in. Basically cutting away the old material Then you bore the sleeve to match the existing cylinders. You stated existing is 0.030 but based on what I am seeing, I am going to assume all the cylinders will need to be bored during a rebuild.

And don't worry about sleeves. Substantially stronger than stock, used in diesels. Plenty of matching numbers blocks saved with sleeves.

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Thank you, that makes much more sense. Do you know what going price is for sleeving and boring so I got an idea? Thanks

No idea on price. Haven't had a block bored in years and rates vary greatly on location and shop. I got 2 quotes to get a crank ground this week. One shop was $125 and the other was $220.

SMC2224 said:

Thank you, that makes much more sense. Do you know what going price is for sleeving and boring so I got an idea? Thanks

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You are gonna have to do some of your own homework, shop prices vary through out the land

I have sleeved quite a few blocks for different reasons, never had a problem. The procedure is:
get the right sleeve, if the other bores are in tolerance and just need a hone, you are good to go. We had chevy sleeves always in stock. Anyway while I have seen others bore until they get into the water jackets for really thick sleeves for a blown application, (Check out LA Sleeve), we would bore the block so the finished sleeve would have at least .0625 wall thickness. I would leave a shoulder on the bottom for the sleeve to bottom out on. Care must be taken when getting close to the bottom with the sleeve that you did not break that, as we used a 10 lb sledge hammer to drive it in. You will here it when it hits bottom. Then bore out to within .002 and hone out to spec. I am sure there will be nay sayers, but it has worked well for me. Note, freeze the sleeve B4 install, follow the mfg recommendations for bore press. Here is a short video of a block I bored.

SMC2224 said:

This block sat uncovered last winter and was full of water/antifreeze. I’ve torn it down and noticed this crack or knick in the cylinder wall. What do you guys think? It appears to be a Knick to me because one side is higher than the other. A crack would tend to be somewhat flush with a tiny gap? The pistons were seized in there really bad and took some banging to get out. Is this something honing could fix or is this block trash? Zero engine experience btw

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That is a crack. A score would be straight. You can have it sleeved, but first mike the other cylinders. If they are already at maximum oversize, you will have to decide if you want to sleeve all the cylinders. Not cheap, but 350s are becoming less than common, so think about it.

J. B.

Check the rest of the block,very,very carefully for cracks. Block left out all winter, uncovered,I would assume water got in and froze,causing that crack. But wouldn't be surprised to find a cracks in the lifter gallery area,where most people wouldn't think to look. Anywhere where water could get in and freeze,is a potential cracks are. Blind bolt holes, any direction around a water jacket,or oil passage. Also a little tip for you and any newb on assemble make sure any blind bolt holes are clean and dry liquid or grease can get in blind bolt holes and as you are tightening a bolt create hydraulic pressure and crack or even pop part of a block off. @Craig Nedrow hadn't heard the name L.A sleeve forever we used them like 90s ish. Are they still around?

I vote for a future boat anchor. Don't waste your time or money on it, look for a re-man from summit racing or similar retailer.