Headgasket?

[black rust]

After swapping the heads on my 305, whenever I start it up, it burns coolant. Not right away, it takes at least 30 seconds of running for it to do it. The smoke looks like it is coming from the passenger side header. It almost looks like coolant is leaking onto it, but I can't see anywhere that it is coming from. Does this sound like I messed up the headgasket or maybe the intake manifold gasket? Other possible ideas?
EDIT: I'm also seeing a little white smoke from the radiator if I remove the cap.

 

[chevyuser74]

pressurize it and see what it does, warning if it is filling up your cylinders, u might have to pull a plug or two and crank it to get the antifreeze out.

 

[black rust]

If I remember right, when I put the coolant in, I left the cap off to bleed the engine, and it burned worse when I did that. It first did this saturday, and I was able to start it easily today, so no major amount of coolant in the cylinders, I think, but I also drained some coolant to make sure I didn't put too much into the cylinders if it was a headgasket problem.

Now that I think about it, I let it sit for a few hours after I put the coolant in it the first time, and after that it would barely crank if it was in the right position, almost like there was something in the cylinder. I may have just answered my own question.

 

[chevyuser74]

if its going into the cylinder via the head gasket, when its running it should blow out the radiator like ol faithful, did u have your heads checked for cracks?

 

[black rust]

Not by a machine shop, but there weren't any noticeable cracks when I looked at them. I'll fill it up again and check that.

 

[chevyuser74]

could be something as simple as a hairline crack, that u wouldnt neccessarily see, they vacuum test or something, im sure 4x4high would know exactly what they do, hes an automotive machinist.

 

[4X4HIGH]

Sounds like you have a cracked head. 305 heads like to crack when they get hot. You said you did not have a machine shop inspect for cracks, did you have them resurfaced before installing them? Are these the same heads that came off the engine or are they replacements? To check for cracks the heads are magnafluxed. You can easily have a crack that isn't visable to the eye but the magnafluxing will detect it. I've seen and tested so many heads over the years that i can see what others can't see. You can bring me in a head and i'll look at it and i can usually tell you "this head is cracked" and they won't believe me so i'll bring them in the back and mag the head in front of them and make believers out of them.

 

[Kenny78]

Trust 4X4 on this one. The head(s) will have to come off regardless, so you would be time frustration ahed to have them inspected. I cracked a TBI head that would drain a pencil sized stream of oil when hot. It was my first time to crack into an engine, what a nightmare!! Back on topic, pulled head and couldnt see any sign of crack. Maggged it and I was on my way to Oreilly's to buy replacement.

 

[black rust]

Figures, bought the heads used from a guy that promised they were still good. I think this is the point where I say I'm done, I'm giving up. The truck will now die a painful and slow death. Thanks for the help guys.

 

[Hogback Fabrication]

It is possible that you have a leaky head gasket.

Did you use a torque wrench on the bolts? With a criss-cross pattern that slowly increases up to the specified torque?

IIRC there are 17 head bolts on a SBC and torquing them correctly takes a little while, there is a specific order and procedure.

 

[4X4HIGH]

Figures, bought the heads used from a guy that promised they were still good. I think this is the point where I say I'm done, I'm giving up. The truck will now die a painful and slow death. Thanks for the help guys.

Not that big of a deal, just pull the heads and have them checked. If one is found to be cracked then ask the shop if they can supply you with another replacement head, either new or rebuilt. Make sure that you have both heads resurfaced before installing them again. Just let this be a lesson learned that just because someone "promised" they were still good doesn't really mean anything. Always have something like this checked by your local shop before installing to save this headache from happening again. Can you ask for your money back if they are cracked (i'm assuming you bought them)?

 

[black rust]

I did torque the heads in the right pattern, in three increasing increments (25.45.65, like the haynes manual said.) I'm giving up because I've been trying to get rid of this truck for over a year now and everytime I fix something, something else completely unrelated breaks and I just want it gone one way or another. I doubt I can get my money back for the heads, and I don't want to put even more money into this truck.
Is there any way for sure to know if it's a cracked head and not a headgasket without pulling the heads?