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Okay I blew a head gasket on my 350, I was using whatever the blue colored ones are that you can get from kragen for 50 bucks and its the second time one of these has blew on my, last year the right head gasket blew now a year later the left one blew (I did replace both last year.)
Another Note: My heads are good, they aren't warped I had them checked out.
I was wondering what kind of gaskets y'all recommend me get.
A link from Summit Racing would be desired (:
Thanks!
is the deck flat a lot of the newer chevy have a choppy finish if this is a hi cr engine ? are the fire rings hanging in the bore? to much timing will and preigition make the head gaskets go. if you do not think you have any thing wrong than use a MLSfel-pro or cometic they will not blow out
This basically a stock block, it only has an intake and headers, as far as timing goes its tuned perfectly, no-preigntion or "pinging", throttle nock, etc. I'll go ahead and check these gaskets out, thanks for quick reply!
Edit: Shoot they want a size, what is the standard bore size for a chevy 350?
You didn't gouge them when you put the heads on? I know sometimes it can be a pain to line up the dowel pins when your putting head back on when the motor is in the truck. I've used those low cost blue felpro head gaskets you can buy from just about anywhere on a couple motors and never had problems. I have a friend who builds a lot of small blocks for people and he normally uses these gaskets too for anything that is under I would say 10:1 ratio and I don't think he has had any problems either.
I don't run it too hard I rarely ever take it about 3700 because of the gas prices. Its a possibility that I gouged the gasket upon installation because we did have a tough time lining up the left head and thats the head that happened to blow. I got the gaskets recommended and hopefully I don't have to tear it down again in a year.
Thanks for the help guys!
I usually leave the stamped steel rocker arms on when I reinstall heads. You can get a good grip on the head by putting your fingers under the rockers.
you would of had to really gouged them and it would not have any thing with blowing the fire rings out? i cut many heads and blocks on my mill. i think your deck is not flat or the heads or both and if you say there are flat how do you know ? how did you check them ? and were they check for twist and like i said many chevy decks are very choppy .i have use stock fel-pro head gaskets with alot of cr but every thing has to be dead flat
They were checked by a machinist and I don't know what "fire rings" are whats the deal with those?
yes but was the block ? the fire ring seal up the heads to the block look at the head gaskets they are the metal ring around the bores of the gasket . you engine sounds like a 427 a guy had he could not keep head gaskets on it they studed the heads and cut them flat but they still would blow it had to much timingQuote:
Originally Posted by 79C10
denny were do you get all them pics ? nice job denny i would add that if the head or the deck is very choppy and you can check the surface contact with carbonless paper from goodson if the surface is bad it saw on the fire rings so i like the finsh to be very good
This guy I know had a cutlass and he said he was running so much cr he had to replace head gaskets every month. I don't know about olds motors but that sounds really excessive. He must have been running like diesel cr.
chevy have a good head bolt patterns on the small block and the big block look at your timming fuel air mix find a new machine shop to check your stuff if you blow head gaskets the block can move and so will the heads i have had over 14to1 with stock type head gaskets i have fix blocks that have had blow thru they moveQuote:
Originally Posted by Gerald Streeks
When you say you used the blue gaskets, do you mean the plastic-coated garbage ones that GM sells? We've had two sets of them, both sets blew on the same hot day, just melted the coating.
WHEN YOU INSTALL THE GASKETS,ARE YOU MAKING SURE YOU ARE TORQUing THEM TO SPECS AND ALSO ARE YOU MAKING SURE YOU DO THE CORRECT SEQUENCE. I START OUT AND TORQUE THEM AT 50 AND THEN 60 AND FINALLY 75 AND THEN I WAIT ABOUT 5 MINUTES AND RETORQUE THEM ,,(AGAIN)CLOCK WORK YOUR WAY OUT,FROM ALSO DID U CLEAN THE SURFACE PERFECT,,, THERES IS NEVER TO MANY TIMES TO CHECK THIS OUT,,THIS MUST BE ALL THE SAME (YOU MUST USE TORQUE WRENCH)Quote:
Originally Posted by 79C10
THIS WILL CAUSE A PROBLEM ,IF YOU DID NOT CLEAN AREA....
The blue ones at the parts store are usually Fel-Pro Permatorques. They're good gaskets, I have a pair in my truck.
To RPope, the coating melting off should have nothing to do with the head gasket failure. The coating is a lubricant that allows the gasket to crush properly during the first torque sequence. It eliminates the need to retorqe after heat cycling the block. This is the same concept behind the Permatorque gaskets. Mr. Gasket's head gaskets are made of a material called Grafoil by Garlock. Grafoil gaskets are made of graphite powder pressed on to a stainless steel perforated core. They are also self-lubricating because of the graphite and have very high temperature capabilities. We use grafoil gaskets on superheated steam pipes with temperatures up to 1500 degrees F. Grafoil is fragile, though, and if you're having trouble lining up your heads then you don't want to use them. Other types of head gaskets are multi-layer shim gaskets. They're basically stacked layers of steel. They don't compress which can eliminate some of the distortion that occurs while torquing the heads. They're reuseable, too. The only experience I have with them is on my dirtbike. The cheapest head gaskets you get are steel shim gaskets. These ones are the ones that need to be retorqued after heat cycling the engine. Copper gaskets aren't strong enough to resist blow-out on their own and require the block be o-ringed. A groove is cut for the gasket to sit in and the block supports the gasket and gives it strength. Copper gaskets are not for the street. They make good header gaskets, though.
Back to you, 79C10. Buy new cylinder head dowels, it will make installation of the head more easy. You can pull the old ones out with pliers, but be careful. You don't want to chew up the top of the block. A safer and easier alternative is to just push them trough with a punch and into the water jacket. They wont do any harm down there. New dowels are supprisingly cheapest and your Chevy dealership. They wont have part numbers for your older engine, order them for a 97 Chevy pickup or something, they're the same. They cost about $3 for all 4. My local automotive parts store wanted $12 for the 4 of them and they had to special order them. The dealer will have them in stock.
Don't use silicone on your head bolt threads. Use a teflon pipe thread sealant PASTE or something like Permatex #2 or Aviation Form-A-Gasket. The Av. Form A Gasket will make the best seal, but I like the teflon because it lubricates the threads of the bolt for more consistent and accurate torque values. I emphasize paste because it is my opinion that teflon tape has no place in an engine. It makes little stringies that float around in your engine.
I found the problem, the fire-rings were hanging over the bore, every fire-ring on every cylinder was cracked in half, they were all gonna go at any minute. I put some new gaskets on there (the fire-rings fit nicely), followed the correct sequence & first torqued them to 30 ft lbs then 65 (which is what my chevy book recommends.) Thanks for the help! Ill post pics of the bad gaskets as soon as I can find my card reader.
yes 65 ft pounds the newer vortec heads are about 70 ft pounds,,,,,
good job!!!!!!
There was a crack in every fire-ring, although you can only clealy makeout one in the pic.
http://www.xylicon.com/misc/P1014003_small.jpg
And the block itself (before I cleaned it up of course)
http://www.xylicon.com/misc/P1014005_small.jpg
Last question, is there a sequence for the intake? (its an edelbrock performer) and I can't locate one on their site.
Thanks again!