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Old 02-17-2019, 02:53 AM
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I can't tell how smooth the block deck is from the picture.

I would have the heads resurfaced but you might want to also consider using a different head gasket as well.
Old 02-17-2019, 02:57 AM
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Originally Posted by 1FastBrick
I can't tell how smooth the block deck is from the picture.

I would have the heads resurfaced but you might want to also consider using a different head gasket as well.
I've just ordered GM 12498544
Old 02-17-2019, 08:20 AM
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Originally Posted by GQLS1
I've just ordered GM 12498544
those will be fine, in post #18 the top picture it appears the heads have some VERY deep gouges right by the water jacket. I would definitely take them to a machine shop and see if they can be cleaned up
Old 02-17-2019, 10:26 AM
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Copper spray is your friend here. Permatex 80697

I'd use the graphite gaskets or copper spray a new set of LS6 MLS gaskets. Use your thumbnail to feel for depth of scratches, you really shouldn't feel much if any of them. If present you can have em machined or use the home doer upper system of a flat surface and sand paper. Theres a bunch of vids on youtube about it. Its not a new idea by any means but with time and patience you can achieve the same results as a machine shop

Something like this



But your probably going to be fine with new gaskets, bolts and proper torque spec.
Old 02-17-2019, 01:23 PM
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Thanks again for the replys. I've read conflicting advice about copper spraying mls gaskets. Is it OK to do to the GM gaskets? Cheers
Old 02-17-2019, 04:21 PM
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Copper Spray works fantastic.

Anyone whos says other is trying to sell you new gaskets or simply doesn't truly know. I've re-used all kinds of LSx MLS gaskets with copper spray successfully. I havent tried reusing head bolts yet, but I will one of these days. The gaskets are coated with some rubber that gets messed up during removal/install. Most of the guys who re-use MLS from a non leaking good running car don't clean the gasket surfaces so the rubber sealer stays in place. Anyways if the surface is smooth enough not to catch any of your finger nail and you get new bolts I'd use copper spray and go. If you have access to local parts at trade prices and most of all are not in a huge hurry? Aint never a bad plan to install new gaskets. Its always better, just not always convenient, or cost effective. Prices have come down a good bit on these though. I like the MAHLE brand LS6 5 layer for small bore. Hope this is of some help

toss a few coolant pucks in there when your done too. AC Delco 12378255
Old 02-17-2019, 05:32 PM
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Originally Posted by 1FastBrick
The finish on those heads is too rough for an MLS gasket.

It appears that it was originally sealed with a Graphite style head gasket
Good point on the roughness and using with MLS



OP, yes take them and have them decked/milled. If you don't want to raise compression tell them to take the least possible off, if you do, now is the perfect time to add a little.
Old 02-18-2019, 01:27 AM
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Thanks for all the great info everyone. I dropped the heads off today to be cleaned up. The blocks all clean & ready to go!


Old 02-18-2019, 03:24 AM
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For future reference, we have 2 bore sizes of mls gaskets that will work with notched heads.

And copper spray isnt an end all be all. Its a pretty terrible idea to spray on top of the flouroelastomer etc coating on a gasket also. Im sure that gasket companies know well more than you or I about that though. It can also contaminate the cooling system. Or cause sealing issues itself by being unevenly applied or running.

Ps im not trying to sell gaskets, im giving actual professional advice. I dont care if you buy the gaskets from us or not. We offer the option regardless though.
Old 02-18-2019, 03:53 AM
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Originally Posted by tech@WS6store
For future reference, we have 2 bore sizes of mls gaskets that will work with notched heads.

And copper spray isnt an end all be all. Its a pretty terrible idea to spray on top of the flouroelastomer etc coating on a gasket also. Im sure that gasket companies know well more than you or I about that though. It can also contaminate the cooling system. Or cause sealing issues itself by being unevenly applied or running.

Ps im not trying to sell gaskets, im giving actual professional advice. I dont care if you buy the gaskets from us or not. We offer the option regardless though.
Thanks mate, thankfully I don't have the notched heads. I sourced some GM gaskets locally here in Australia. Do you ship internationally, just for future reference?
Old 02-18-2019, 07:31 AM
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I'm not trying to spend your money but I must mention that now would be an excellent time to replace lifters if they haven't been replaced already. Probably not a concern if the mileage on the motor is low.
Old 02-18-2019, 12:20 PM
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Originally Posted by 98cherrySS
I'm not trying to spend your money but I must mention that now would be an excellent time to replace lifters if they haven't been replaced already. Probably not a concern if the mileage on the motor is low.
x2 this is wise advice

Old 02-18-2019, 12:29 PM
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The lifters were replaced about 5000km ago, definitely would have been a good time to do them though.
Old 02-18-2019, 12:31 PM
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Also good to spray a bit of copper between the layers if reusing the head gaskets. Not a lot just some.
Old 02-18-2019, 03:51 PM
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Id recommend not making a peanut butter and copper spray gasket sandwich.

We do ship internationally every day!!
Plus our gaskets are a TAD thinner so they give better cr and quench. They can be used on non-notched heads also.
Old 02-18-2019, 06:28 PM
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Originally Posted by tech@WS6store
Id recommend not making a peanut butter and copper spray gasket sandwich.

We do ship internationally every day!!
Plus our gaskets are a TAD thinner so they give better cr and quench. They can be used on non-notched heads also.
What's The part number for the gaskets for Notched heads on a 5.3? I need to order them this week .

Thanks
Old 02-18-2019, 06:51 PM
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Using them on a 4.8/5.3/5.7 is this one

http://www.ws6project.com/user_stor/...oducts_id=6909
Old 02-19-2019, 12:01 AM
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Nice and clean, now just waiting on gaskets and bolts.


Old 02-19-2019, 08:31 AM
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Originally Posted by GQLS1
Nice and clean, now just waiting on gaskets and bolts.

What took so long! Lol. Geez, you move fast. Looks good!



Old 02-20-2019, 05:12 AM
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Almost all back together. I would have pushed on and finished it tonight but I don't think the neighbours would appreciate the sweet sound of the LS at 11pm.



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