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Discussion Starter #1
Hey guys. I just put a new head gasket on my 71. Its got a motorsports cam in it also. When I turned it over by hand it was smooth and perfectly in time. But when i fired it up it had a miss. So I figured the timing was off. Wrong! Its right. I balanced the carbs, checked the plugs, wires. Then I did a compression check. Number 3 has no compression at all. Im thinking either I blew a hole in the piston, broke a valve, which they were all checked by a machine shop along with the head. I dont see how a valve could be stuck in the down position unless its bent but then it would hit the piston right? Question number 1 :How much am I looking at for a stock rebuild? Im figuring that getting one from a junk yard would most likely be in need of a rebuild also so that would defeat the purpose. Question number 2: What else could be the problem is my second question? Also the car is in good shape with nearly new everything under the hood and shock and paint and stuff like that so its not ready for the junkyard. Thanks everyone for your input. Mark
 

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NO compression? must be a valve because you have run your car for lean for long time before you burn out piston. The valve does have to hit the piston, it may be not seated properly. hit the #3 valve springs mallet. May be you lost the valve retainers. What's your cam? May be your valve is staying open all the time due to a unproper tappet.
 

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Im preparing to move saturday morning all of the paper work on the cam is packed up. If you have a motorsports catalog its the third on on the list. And yes I got all new rockers arms, springs. I did a proper wipe pattern test also. I turned the motor over by hand 10-15 time before I tried to start it to make sure it was in time correctly. Tappet you mean what? Im going to pull the valve cover in the morning and see what else I can find. I can put a screw driver in the spark plug hole and see where the piston is and then pull it out and hit the starter and the piston is going up and down. The car didnt hardly run but a few seconds before it started missing. It didnt and still doesnt burn any oil nor did it knock or anything. Hope that helps cause I guess im screwed. Laterzzzz Mark
 

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MSA still haven't sent me a new catalog yet. I lost my old one. but I think that's 490 lift with 270in/280ex cam. tappet, i mean the valve and rocker arm clearance. if your rocker is too tight, the valve doesn't close during compression. Won't you take the valve cover off and turn over the engine and see what's going on with the #3 valves? You should be able to see if your valve is moving properly. I doubt it since you are getting no compression, but it could be your valve stem seals too. I replaced mine with shorter one because my head guy said the OEM seals are too tall for my cam (480 lift)

If you are not buring oil then it's not your piston. When you blow a piston, you'll get lot of blow by.
 

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I bluw a head gasket a few years back and I picked up a used engine for 500 bucks
at a outfit that had nothing but Jap engines .It seem that over there they have no
smog stuff ,so they have to get a new engine after a min. amount of miles .The one
i got is still runing great .I'd do it again for sure .
 

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Warped ??

You replaced the head gasket, but you didn't mention if you surfaced the head. If the last gasket let go because of a warp caused by overheating the new gasket won't last either. The reason I mention this is mine required removal of .030 on the ends to flatten it after a blowen gasket. So the arch in the middle prevents compressing the new gasket, I've noticed the gaskets seem to let go around the 3 and 4 pistons. If this is the case make sure the cam bases get leveled and you'll need cam tower shims. Hope I'm wrong. A tweeked valve might be a blessing.
 

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Discussion Starter #7
Ok guys. I double checked the valves this evening and they are all rising up and going down. The piston is going up and down but I get absolutly no compression on #3. All the others are 155-160 which im told is pretty good. I guess its toast and Ill have to find a shop here in the atlanta area. Anybody know one reliable? And resonable priced. Money doesnt grow on the trees around my house. Thank again for all the responses. Laterzzz Mark
 
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