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First timer Head Gasket replacement

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Old Sep 2, 2011 | 08:41 AM
  #61  
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Originally Posted by sly vette
I see that the head gasket appears to be compromised however I still believe the heads are cracked due to the fact that you are showing water on the top of the header flange.
Heads are being pressure checked, put on level, and checked for cracks as we speak. I discovered with the help of the machinist when I took them in that they have been milled before.

Good pictures and even better, your pistons have been changed. You might want to go with thinner headgaskit.
How can you tell they've been changed? The top of the piston read 040 just FYI
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Old Sep 2, 2011 | 08:54 AM
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Originally Posted by jkjazzsax
How can you tell they've been changed? The top of the piston read 040 just FYI
The pistons have valve relief "eyebrows" on both sides of the piston, allowing them to be installed in either bank, which is typical of "rebuilder" pistons.

The "040" indicates an .040 overbore, meaning for sure it's been overhauled. There may also be a part number laser cut into the piston depending on how long ago they were manufactured.

It will be important to measure how far down in the hole the pistons are; the best way is to beg, borrow or buy a dial indicator and magnetic stand - a cheap one is fine. There's a simpler way that works as well if you're not interested in going that route.
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Old Sep 3, 2011 | 11:55 PM
  #63  
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Confirmed today with the machine shop that the suspect head was cracked

They are looking for a remanufactured head with the same casting number.
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Old Sep 4, 2011 | 12:01 AM
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Well, Sly gets the cookie - he called it

Might be worth thinking about a set of Vortecs...
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Old Sep 4, 2011 | 02:23 PM
  #65  
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its great to see the future of the hobby helping you. i remember helping my dad in the garage, but my dad always had cool cars a 60 Plymouth station wagon I'm 6'4" now and i think The fins are a foot taller than me! and a 65 Plymouth fury 2 3:55-1 posi rear 3 on the tree and a slant six someone ordered that right! but enjoy it he will remember every minute his entire life.
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Old Sep 5, 2011 | 07:38 PM
  #66  
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Did the headers today. My 5 year old son helped me sand and paint. Not the best pictures but you get the idea.


As they came off the car, covered in grease and rusty:





Finished product. I used Rustoleum high temp 2000 degree paint on these guys. Sanded with 100, then 150 then 200. After that I painted two coats of primer then 3 coats of paint:








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Old Sep 7, 2011 | 09:55 AM
  #67  
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Originally Posted by billla
Well, Sly gets the cookie - he called it

Might be worth thinking about a set of Vortecs...
Not to hijack but Im going down the Vortec route. Will it be OK to re use my stock head bolts once they have been cleaned up? I also ask this for the OP as I see no reference in this thread to buying new bolts.
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Old Sep 7, 2011 | 10:21 AM
  #68  
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Originally Posted by jotto
Not to hijack but Im going down the Vortec route. Will it be OK to re use my stock head bolts once they have been cleaned up? I also ask this for the OP as I see no reference in this thread to buying new bolts.
I tend to replace any torqued fastner if they're removed - but this is a personal preference and absolutely not required. Go ahead and clean up and reuse your head bolts - remember that they need sealant on them.

If you do want new, the best deal is oddly from GM under P/N 12495499; sells for around $35.

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Old Sep 7, 2011 | 11:31 AM
  #69  
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Originally Posted by billla
I tend to replace any torqued fastner if they're removed - but this is a personal preference and absolutely not required. Go ahead and clean up and reuse your head bolts - remember that they need sealant on them.

If you do want new, the best deal is oddly from GM under P/N 12495499; sells for around $35.

Thanks for the part # I was looking at ARP bolts @$78 so any saving is a bonus.
With regards to installing them, would you use an assembly lube such as ARP Ultra Torque or a sealer such as the ARP Teflon Sealer? I was going to use the Ultra Torque on the head bolts and the Teflon sealer on the screw in studs I have installed. The studs are in through holes so need some kind of sealant. Also heard good stuff about Permatex High Temp sealant.
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Old Sep 7, 2011 | 11:35 AM
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ARP are the best...but for a mild build the GM bolts are fine

No assembly lube, just sealant
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Old Sep 7, 2011 | 12:21 PM
  #71  
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I've been using the stock head bolts, with sealant, on my Vortec heads.
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Old Sep 13, 2011 | 09:22 AM
  #72  
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Finished getting the heads on there last night. Here are some pictures:

Finished product of the paint to the headers. I used 2000 degree high temp, 6 coats with 2 coats of primer:



Painted the heads to match the block. Don't worry, I scraped off the excess paint on the exhaust. I learned a good tip from my neighbor though - if you put vaseline on the parts that you don't want paint on, it won't stick to it:





This is what came out of the oil pan when we drained it Looks like MUD!






Installed the heads!!!!





Last edited by jkjazzsax; Sep 13, 2011 at 09:24 AM.
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Old Sep 13, 2011 | 12:20 PM
  #73  
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Nice work overall

You may want to quickly paint the intake side of the heads - being iron, the unpainted portion above the intake will rust pretty quickly.

Oil looks bad

Last edited by billla; Sep 13, 2011 at 12:39 PM.
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Old Sep 14, 2011 | 09:35 AM
  #74  
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Heads were torque'd down to spec last night. 30/50/60 ft/lbs. Boy, was I exhausted after that one Glad that part is over.

Started attaching the headers to the heads and ran into a few problems, mostly fitting issues with the old headers attaching to the new head. I grew frustrated after trying to get the far back bolt through the header into the head (not very much clearance against the firewall) and walked away before I hurt myself or made a stupid decision.

So far I think I have about 10 hours into this rebuild project. Not bad!

I do have a question on the temp guage. For some reason the PO had a temp guage and individual cluster hooked directly up to the block instead of running it to the guage cluster. It just sat under the hood... I know... stupid idea. How are you going to see the guage under the hood

I can't locate where the wire is that you hook into the temp guage that goes to the cluster inside the dash. Know where/what I can find it? I'm hoping the PO didn't cut the wire...

Oh, and while in there, found the source of why the Speedo wasn't working. The cable going to the transmission had falled on the headers and burnt through Going to order a new one on Friday.
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Old Sep 14, 2011 | 10:16 AM
  #75  
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Sounds like you got this one under control. On my 71 the temp wire is a green wire that is sleeved in a heat resistant sleeve that runs with the harness that also supplies the alternator.
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Old Sep 15, 2011 | 09:48 AM
  #76  
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Newly fresh painted headers were installed last night. I had some difficulty with these guys. The bolt on drivers side very back (#4 Cyllinder) was a BIATCH to get in there. The headers have very little clearance to get a wrench on, plus when mounting them it's very difficult to get all the bolts started without putting them in the heads all ****-eyed. I had to put one in, put another, remove one, add another, remove a different one... kind of like in a star pattern until they were all started. But alas, they are in!




Next was the rocker arms and push rods. Note to people who haven't done this before - DEFINITELY do this BEFORE putting on the intake manifold. That way you can make sure the push-rods actually go into the lifters (you can't see them if you put the intake on )




Finally I stopped last night by putting the Holley intake on. It was really easy actually. The gasket kit came with the really nice silicone front and rear gaskets for the intake so I didn't have to lay down a bead of RTV. Very good.





I ended the night with a few beers and took off the thermostat coupling and sanded and painted it the same color as the headers. It was looking pretty dirty so why the heck not
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Old Sep 15, 2011 | 09:51 AM
  #77  
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Originally Posted by Roco71
Sounds like you got this one under control. On my 71 the temp wire is a green wire that is sleeved in a heat resistant sleeve that runs with the harness that also supplies the alternator.
Thanks Roco! I did indeed find that wire last night and it was intact Thanks so MUCH! I'll just need to order the electronic temp sensor now... which is here: http://www.zip-corvette.com/ProductD...R-SR&CTitle=&#
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Old Sep 15, 2011 | 10:19 AM
  #78  
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Originally Posted by jkjazzsax
The gasket kit came with the really nice silicone front and rear gaskets for the intake so I didn't have to lay down a bead of RTV.
Nice work overall, but those end gaskets will leak and blow out in relatively short order as previously noted
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Old Sep 15, 2011 | 10:28 AM
  #79  
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What cam did you have in it and are the springs up to the task?

Depending on the cam you may geta little more out of it with an open spacer rather than the 4 hole.

Keep going..
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Old Sep 15, 2011 | 11:04 AM
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Am I missing something or are you missing your pushrod guide plates?
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