Block - Deck surface prep question

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Oct 1, 2007 | 07:42 AM

biggrizzly

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Melting Slicks

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From: Chesapeake Beach Maryland

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Block - Deck surface prep question

Over the weekend I cleaned up block. On the deck surfaces I used a scotchbrite wheel on a drill at low speeds. On some stubborn areas around water jackets I used a scotchbrite wheel on a dremmel. It was a bit more abbrasive. When I was finished all looks good and clean.

What has me worried this morning is that a read a little further in my "How to Rebuild Small-Block Chevy LT-1/LT-4 Engines"; it states "DO NOT use an abbrasive material such as Scotchbrite, since it's easy to create waviness in the deck surface, especially if driven by a power tool."

WTF - Have I screwed the pooch? What is the proper way of prepping the heads? I thought I was doing good. I did a SBC about ten years ago and think that I cleaned the deck surface the same way with no problems at all. Any feedback appreciated.

Thanks - Don

Oct 1, 2007 | 08:43 AM

LTxDave

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From: Marianna FL

Are you not planning on having any machine work done? Its hard to tell from your post if you are just doing heads or a complete rebuild.

Any engine I rebuild gets the deck and head checked and surfaced if needed by the machine shop. I doubt you put enough distortion into the surface of the block that it can't be decked. If you're just doing heads and not a complete rebuild, I don't know what to tell you. There's really no way to fix it with an assembled short block. You could get a straight edge and check the deck yourself with feeler gauges and then decide from there. Good luck.

Oct 1, 2007 | 09:39 AM

biggrizzly

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Melting Slicks

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I'm leaving the block in the car - Not doing a whole engine rebuild. Just heads, cam and intake

Oct 1, 2007 | 09:49 AM

rklessdriver

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From: Dale City VA

With a Scotchbrite on a die grinder its pretty easy to screw up something soft like an alum head surface or intake manifold surface. You have to use very light pressure on soft non ferrous metals.

On something as hard as a cast iron block, IMO you would have to be trying pretty hard to screw it up. It can be done thou... If you are in doubt just get a strait edge and check the deck surface.
Will

Oct 1, 2007 | 10:06 AM

Greg Gore

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From: CLT, North Carolina

Block probably has more waviness from the factory broach operation than you could possibly do with a scotch bright wheel but if in doubt get a good straightedge and check flatness. You don't want to be able to put .004 in anywhere. Another thing you could do is get a good long "Mill Smooth" file and while holding it steady with both hands lightly stroke the deck a couple of times to give you a good visual of what the surface flatness is.

Oct 1, 2007 | 11:38 AM

biggrizzly

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Thanks guys - I have been sweatin' bullets all morning, because I didn't want to pull the whole block to fix some bonehead screw-up. This whole project has gone very smooth so far with no surprises. I hope to keep it that way. I have the car shoehorned into a one car garage doing all my work. It would be pretty interesting fitting a cherry picker in there to get the block out.

I can't believe that a scotchbrite wheel would mess up a cast iron block, but as you guys stated anything is possible in the hands of some people. I will check it for flatness tonight when I get home, just to make me more at ease though.

Oct 1, 2007 | 11:40 AM

Muffin

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From: Merritt Ils Fl

I'll throw in with those who say you most likely didn't hurt the block. A straight edge will tell. Another quick check is a straight edge and a small flashlight. Low spots will show up very quickly. How do you plan to get all the trash out of your cylinder bores, especially out of the ring grooves?

Oct 1, 2007 | 12:03 PM

biggrizzly

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Melting Slicks

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From: Chesapeake Beach Maryland

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I don't know, but I've been wiping and oiling and wiping and oiling. I hope that flushing it with WD40 will clean it good enough. There wasn't too much crud to start with - Any suggestions?