Winter (Now Almost Spring) 350 Fresh-Up Project

Discussion in 'Small Block Tech' started by knucklebusted, Mar 13, 2021.

  1. Dano

    Dano Platinum Level Contributor

    Honestly, it probably makes almost no difference on a 350 car but I'm a resto guy at heart & had a GSX once that I'm 100% sure was the original engine but the block had been decked. Like I said, on a '71 the VIN is on the front anyway so decking wouldn't even get rid if that. It's just the other codes that are on the deck.
    Mart, 72gs4spd and knucklebusted like this.
  2. 72gs4spd

    72gs4spd Well-Known Member

    There are ways of having the block re-stamped. My machinist mentioned it to me in one of our many conversations. It was one of the reasons that I didn’t want to rebuild the original 350 in my car, the most important being I can’t drive the car without it. As he said and I quote, “he hasn’t seen a block that’s 50 years old that had a deck height parallel to the crank centerline. In fact I’ve seen new ones that were too far off for my liking.”
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  3. Dano

    Dano Platinum Level Contributor

    That's why my plan is to build my two #'s matching 350 blocks m/l stock and I have a few spares that can get squared up, blown up (not a 350, lol), stroked, etc.
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  4. knucklebusted

    knucklebusted Well-Known Member

    Today, I used my digital calipers to check the crank. The rod journals and main journals were all 2.000 and 3.0005 respectively. That isn't with a micrometer. I was thinking of buying the Harbor Freight mics and bore gauges to see for myself what shape it is in.

    I can't catch a finger nail on any of the rod or crank journals though they do look like they have minor water/rusty spots on them. At least one rod and one crank bearing look like they have a scuff in them that can't be attributed anything I did taking it apart.

    I've still not gotten a call back from my preferred machinist! Frustrating.
  5. Mart

    Mart Gold level member

    By the looks of your journals, you should be able to polish them. Either taking to shop that has a polishing setup to spin it, or just use the lawn mower starter cord rope trick with 1,000 grit paper cut to the journal width. Works real slick....
    Here's a vid so you get the idea....
    Last edited: Apr 3, 2021
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  6. knucklebusted

    knucklebusted Well-Known Member

    I might give that a try. I have 1000 and 1200 on hand. It shouldn't take much at all.

    At this rate, I may not have much machining done on it.
    Dano likes this.
  7. Mart

    Mart Gold level member

    I never use 500 grit, only 1k. Maybe do the knurled seal jrnl with 500 to smooth over that seal area.
  8. Storm1

    Storm1 Silver Level contributor

    Just take a picture and be done with it :D

    Then let er rip!

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  9. Dano

    Dano Platinum Level Contributor

    I've done similar - Works well. Not sure I'd use 500 but seems to be ok. I'd prob. use something finer for a final step too (500/1000/1500 maybe). I also cut sandpaper upside down on my paper cutter. Easier on the blade.
    Mart likes this.
  10. knucklebusted

    knucklebusted Well-Known Member

    OK, I put the crank back in before I did any polishing and checked it with plastigage. It looks like it is currently .002 standard to me. Anyone see any different? I checked with red (on the left .002-.006) and green on the right (.001-.003) just to confirm nothing was out of whack.

    Second question: Do the bearings look like that because it did sit a lot before (and after) I bought it? Acids in the oil, etc?

  11. Mart

    Mart Gold level member

    Look just stained.. You could 000 steel wool those and they would look like new.
    knucklebusted and sean Buick 76 like this.
  12. knucklebusted

    knucklebusted Well-Known Member

    At least one rod and #4 main have debris scratches in them. The one with the green gage shows it.

    I'm going replace them simply because it is cheap and easy. I was mainly making sure it wasn't already too much undersize for standard bearings.
  13. knucklebusted

    knucklebusted Well-Known Member

    So, I went and bought a set of calipers and bore gauges to check out the crank, rods, mains and bores. I guess with all the machine shops busy and not taking on any more work, I'll have to do a lot myself to get it back together.

    Not looking good to have it back together by GS Nats at this rate with a 350. I could probably pull off a 455 swap in the time allotted.
  14. Mart

    Mart Gold level member

    You are right. You need to do stuff yourself to speed things up.
    I just use .0001 dial bore gage, & a 1"- 4" mic set in tenths to set the bore gage.
    Great for checking rod end roundness along with size.

    Attached Files:

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  15. Fox's Den

    Fox's Den 27 years of racing the same 355 Buick motor

    Looks like a nice expensive set of tools.
    knucklebusted likes this.
  16. knucklebusted

    knucklebusted Well-Known Member

    Checked the crank and block. All the main journals spec out to 3.000-3.000+ a smidge and the rod journals all came in right at the high side of 1.999+ to 2.000. Bores look like they are not tapered by any more than 0.001 with the gages I was using and seem to be pretty round. The ring ridge is non existent once I hit it with a little Scotchbrite pad and got the carbon off.

    I found the serial number on the front and the deck stamping. Deck shows is TB I70 best I can tell.

    I'm going to check the main saddles and rods this afternoon to see what measurements I come up with. So far, it looks like everything is going to come back standard.

    What's the best way to clean it since I'm not getting any machine shops to take it? I saw where oven cleaner was recommended earlier.

    Going to buy a 1/2 inch drill bit to drill out the oil passages.

    I swear, if it weren't for the front cam bearing having a ridge, I'd hone the cylinders, rering, put new bearings and gaskets in it and put it back together. All it really needed was degreasing and external gaskets before I went a little crazy. A lot crazy is dropping the 455 in. :D
  17. Mart

    Mart Gold level member

    Since journals looks so good, what you're doing will work.
    Oven cleaner works with a brush.
    Get these tube brushes at H. Freight to clean out all passages real well.
    Think doctor clean.:D

    Attached Files:

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  18. knucklebusted

    knucklebusted Well-Known Member

    I've already got the brushes in the cabinet when I bought the mics and bore gauges.

    I drilled out the short oil pickup and started the long oil feed down the side of the block but I couldn't find a 12" long 1/2" drill bit I like. All I could find was this deWalt that wasn't really what I thought I needed.

    Does anyone think it would be fine to drill cast iron for the oil passage? This was all they had in stock.

    This was my first choice but it wasn't in stock.

    Making progress but cleaning and drilling is nasty business. Short side drilled.

    Long side drilled as far as I could go with my existing bit.
  19. Max Damage

    Max Damage I'm Working on it!

    That bit looks like it will work ok. Just don't over heat it... I like the Cobalt best, but they aren't always easy to find.

    That engine really was put together right and was maintained too. NICE!
    knucklebusted likes this.
  20. Mart

    Mart Gold level member

    Either should work. You don't need a split point as you already have an existing hole.
    Just pull out to clean chips often, use lube to minimize seizing up way down inside. You will get heat buildup.
    Keep going.:D
    knucklebusted likes this.

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