Hopefully not a cracked block....

[1979C20]

Well, Its odd because my truck has never gotten hotter that 220, for like 5 miles before I realized my heater core was leaking and the radiator was 1/4 full. My truck normally sits between 175-195 with a 180 t-stat. So I honestly dont know why it cracked, or if that heat was the problem. And if that heat was the problem, why didnt I have a problem sooner?

[Grim 82]

Could be this, or maybe it had just finally seen enough heat cycles:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=18711.0

[1979C20]

I would assume heat cycles.

[1979C20]

Took them to the machine shop. He said that the 883's are an older cast so it may or may not have hardened seats. And they 883's arent quite as notorious to crack. They are thicker, the 624's have material removed around the water ports to lighten the head, which makes them weaker and makes them run hotter. So, hes going to pull apart the 883's and check them out. Going to.use whichever parts he may need from my 624's. Going to be about a week or 2 since theyre busy. Ill post back findings.

[1979C20]

Okaaaay! Just called up the machine shop to check progress. Bill, at B&B Machine in Mesa is a customer oriented business man. I went there for my machining when I rebuilt my engine, crack check, heads gone through, block crack check, vats, replace worn valve seats, walked away at 320$. I had problems with getting oil pressure when I brought the engine home and eliminated the oil cooler and know there was oil flowing, but no pressure. I pulled the engine twice thinking I had it fixed and being wrong. I called the machine shop and BIll and Mike came TO MY house and found they accidentally put a metric sized plug in the oil passage way and they fixed it on the spot. Well, When I called and talked to Bill, he said my heads need valve guides and hardened seats installed because they are 70's heads, gonna run me 435$. Then, he said "but since I dont know what happened to the other set of heads, I dont know if its something you did wrong or if its a crack we missed, so I'm going to cut that price in half for you". About 220 And he said he should have them done this afternoon. If you guys ever need machining around Mesa, Go to B&B! And you can even tell them Kyle Taulton recommended you and he might give you a bit of a deal, but dont quote me on that.

[jaredts]

That's a steal!  Hope they work well for you.

[big bear]

great to hear theres still some stand up people out there.

[1979C20]

Okay! Picked up my heads yesterday at 430. Brought em home, got them all torqued down and got the valves adjusted. I used a remote button on the starter to turn the engine to compression for each piston, and cranking the engine caused my fuel pump to fill up the lines and when i was finishing up the last 2 pistons, fuel started puking out of my carv all over.my.wngine bay. My carb is sitting on my passenger wheel well with the fuel line still hooked up. so, i didnt feel confortable pressing the button anymore because i didnt want to explode. I unhooked it from tbe battery and called it a night.

[beastie_3]

Looks good, but you didnt paint them?

[Dr_Snooz]

I called the machine shop and BIll and Mike came TO MY house and found they accidentally put a metric sized plug in the oil passage way and they fixed it on the spot. Well, When I called and talked to Bill, he said my heads need valve guides and hardened seats installed because they are 70's heads, gonna run me 435$. Then, he said "but since I dont know what happened to the other set of heads, I dont know if its something you did wrong or if its a crack we missed, so I'm going to cut that price in half for you". About 220 And he said he should have them done this afternoon. If you guys ever need machining around Mesa, Go to B&B! And you can even tell them Kyle Taulton recommended you and he might give you a bit of a deal, but dont quote me on that.

I don't mean to be a jerk, but it sounds like this guy rebuilt your new heads wrong and lost your old heads. I'll give him points for honesty, but I'm not really seeing a good reason to give him any business. I hope you don't find out other stuff he did wrong the hard way.

I hope you get it all sorted out but you might consider avoiding this guy in the future.

[1979C20]

I called the machine shop and BIll and Mike came TO MY house and found they accidentally put a metric sized plug in the oil passage way and they fixed it on the spot. Well, When I called and talked to Bill, he said my heads need valve guides and hardened seats installed because they are 70's heads, gonna run me 435$. Then, he said "but since I dont know what happened to the other set of heads, I dont know if its something you did wrong or if its a crack we missed, so I'm going to cut that price in half for you". About 220 And he said he should have them done this afternoon. If you guys ever need machining around Mesa, Go to B&B! And you can even tell them Kyle Taulton recommended you and he might give you a bit of a deal, but dont quote me on that.

I don't mean to be a jerk, but it sounds like this guy rebuilt your new heads wrong and lost your old heads. I'll give him points for honesty, but I'm not really seeing a good reason to give him any business. I hope you don't find out other stuff he did wrong the hard way.

I hope you get it all sorted out but you might consider avoiding this guy in the future.

No, he actually had both sets of heads. He asked me if i wanted the old ones back, even. I yold him to keep them for the parts because i dont want to store them. He is an honest hard working customer oriented business man. If he wasnt he wouldnt have been in business for 15+ years.

Beastie, no i didnt paint them, because i dont know how long it will be before i have to start over from scratch on the motor. I should have bored the engine when i first built it, but i was an impatient teenager and wanted a truck. So the cylinders were pretty scratched from the pistons slopping around. And i need my truck back, my parents are getting impatient that i keep having to borrow vehicles. So i figured skip the hassle of painting them and throw em in there naked. The match my water pump now, as it was replaced a few weeks ago due to a hole in the back plate.

[1979C20]

Alright! Finished up puttin her together today! One thing that i am extremely upset about, and about to go to checker and raise heck, when i first started it up to time it and get water in the block, the temp gauge raised to about 160 so i figured the tstat opened. I filled the rad to the top and started her back up to adjust the idle and look for vacuum leaks if any. Took me avout 10 mins. I went back and looked at the temp gauge. 260. Oh S***. The machine shop installed little warranty tags on the heads, and the center of the tag will melt out of it if the temperature goes above 260° well, sure enough, they started melting, which may void my warranty. So i popped the water neck off and pushed the center of the tstat down with a screw driver and it started steaming and most of the water drained out of the radiator. I just replaced the tstat like 2 months ago, and it seized and could very possibly have damaged/warped/cracked my brand new(technically) heads. So i pulled it out and my truck is running at 180 steady. Im very unhappy. Checker will be buying me a new engine if anything is wrong with my heads. I will make sure of it. on a second note, i finished putting my truck back together, and drove it about 8 miles tonight. Im amazed with the power it has with the taller tires on the rear. It doesnt have as much off the line acceleration, but i spun the tires all through first gear and halfway through second, at about 3n4 throttle and easy acceleration off the line. I will post pictures tomorrow when i get to a computer for photobucket.

[1979C20]

I'm going to repost a few pics just so its easier to follow, and because I uploaded the others and I'd rather post the IMG code.

Got the sexy heads back from the machine shop.


Slapped em on and torqued them down. there is a specific torquing order for the bolts, from the center out in a clockwise spiral. and I
     torqued them in a certain pattern, 30, 50, and then 65, in the special order.


Got the pushrods and rocker arms in and adjusted. Bring the cylinder to TDC compression and then tighten the rocker nut while turning 
     the pushrod. When the pushrod stops turning, turn the nut another 1/4 turn.


Set the intake gaskets on with a thick bead of RTV around the water port corners, both sides of the gasket.


Got the intake torqued down to 30lbs. and the carb bolted on and vacuum lines ran.

Valve covers on.


The fitting for the temp sensor to the block was out of round some how. /:


Quick fix with a bench vice. (:


And here is that warranty tag, you can see the hole in the middle where the metal melted out, I'm guessing its something soft like lead
     or some sort of solder. It dripped on the head and the motor mount clam shell.

[jaredts]

I've put several top ends together and I admit its been a while, but I don't think I've ever seen the rtv around the end water ports.  The only rtv I thought was required was on the front and back if you do that instead of using the small gasket pieces   I'll have to look it up soon myself, but on the rocker nuts I thought it was zero pushrod play and then 1/2 turn?

[1979C20]

I looked around all over the web and i read that with hydraulic lifters to take it to zero play and another 1/4 turn. The rockers arent rattling, so it should be fine.