what does a properly prepped block look like?

Facime

Leather work expert
Jun 1, 2006
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Ok well, I saw my block at the machine shop today. I was not entirely sure that the block surface was ready for a Cometic MLS gasket (RA50). The machine shop owner swears its MHG ready but Im not convinced. Since Ive never seen a block that was supposedly prepped for a metal gasket, can someone actually take a picture of one for me? I mean Ive read the description (pretty much mirror shiney right?)

I got tired of sorting through threads trying to find a picture of what RA50 or better looks like.

If anyone can help me out that would be great.
 

jdub

Official SM Expert: Motor Oil, Lubricants & Fil
SM Expert
Feb 10, 2006
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Valley of the Sun
Don't have a pic, but if you can feel machine marks with your fingernail...it's not good enough.
 
C

cnewingham

Guest
Here are the best photos I have, you can see the lint on the block (not scratches). Hope it helps:

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jetjock

creepy-ass cracka
Jul 11, 2005
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Purty. Not all shops have a profilometer but any machine shop worthy of the name should have at a set of surface roughness standards. They're like what, $80 to $100 for the set? Ask to see those. It'll give you a perfect idea of what it should look and feel like.
 

ma71supraturbo

Supramania Contributor
Mar 30, 2005
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cnewingham said:
Here are the best photos I have, you can see the lint on the block (not scratches). Hope it helps:

sm_photo_missing.jpg

I had to take off a ton of material to get rid of all the pits/grooves by the coolant passageways -- so much, in fact, that I had to return my 1.4mm mhg and get the 2.0...
 
C

cnewingham

Guest
I had to take off a ton of material to get rid of all the pits/grooves by the coolant passageways

believe it or not you could not feel these areas of discoloration with your finder nail at all. I figured they are just stained (haha)
 

Facime

Leather work expert
Jun 1, 2006
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wow thanks guys, those photos (while hard to see some of the detail) really helped. I was actually thinking that everyone had their blocks prepped like IJ's. So when I went to pick up the block today I was concerned that it wasnt smooth enough. The head looked very nice and was much closer to a mirror (I suspect because its aluminum...right?) The thing that has me so concerned is that the shop didnt even know what "RA" was. Granted when I took the parts in to them there was a language barrier but I distinctly heard "diamond cut"

As it turns out, when I went to pick up the block they showed me the pistons and rod bearings...

Junk

So, Im doing a full bottom end rebuild now. I'll take pics when I get everything back, and if its not smooth enough I'll find a shop to fix it. The price I paid for what they did was nothing, and they did it super fast. But like we used to say in the printing business: "You want it cheap, fast and perfect? Pick two and call me back"
 

Facime

Leather work expert
Jun 1, 2006
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empera said:
how much does a machine shop usually charge to prep/lap a block.

I paid $120 for the head and block. And that included taking both apart (basically I gave them a seperated longblock)
 

tte

Breaking In - in progress
Mar 30, 2005
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Northern California
ma71supraturbo said:
I had to take off a ton of material to get rid of all the pits/grooves by the coolant passageways -- so much, in fact, that I had to return my 1.4mm mhg and get the 2.0...

I just had my head and block machined...The machine shop used a CBN machine and produced finishes esp for metal head gaskets. I cannot feel the machine marks and it is very hard to see them.

Is that stock pistons in your block?
My pistons are stock and have a thermal coating on the top.
IJ told me that genuine toyota pistons come with a coating on top.

Maybe you cleaned yours off.

Cheers,
Roy