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I could use a little info on replacing the head gasket on a series 10 (pretty sure, 1981 model). Do I have to pull the timing cover or can I release tension on the timing chain and lift the head off?

take a zip tie and slip it through the timing chain to keep the cam sprocket from changing it's index. the tensioner doesn't fly apart on these trucks (like the old dats and toyotas) it would be a good idea to set the slack side guide if the chain is stretched but not absolutely necessary.

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So do I need to remove the cam sprocket, or can I just get the chain loose enough to take it off the sprocket and leave the sprocket attached? This is my first head gasket job on an over head cam, and I do not yet have a manual for this vehicle. With that said, I may have more questions as things progress. Thanks and thanks again.

Alright man, first thing you need to do is get the manual, or download the PDF one from the info section of the site.
The timing chain tensioner is spring operated, and you can release it by taking a screwdriver (standard) and depressing the little white plastic screw.
To avoid any kind of problems with having to set the timing, bump the engine over until the timing mark on the cam is touching a link in the chain. Use either a ziptie, as Where's all the luv at?suggested, or take a clothes hanger and put it through the link. This will definitely keep the timing where it's supposed to be as long as you don't move the crank until the head is back on with timing chain installed.
Good luck!
Oh, and check for warpage...
I'm not too sure how much the engine changed between 80 and 81 tho...
-ret

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1980 4X4 LUV daily driver, as stock as can be.

how do you check the block for warpage? what sort of tool do you need? Im sure it says everything in the manual huh

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The streets of Tulsa were NOT made for minis >.<*

i believe he was talking about head warpage lol my dads a machinist we use his surface plate

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No luv right now =(

Surface plate? where can one acquire one of these? im guessing its a machining thing

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The streets of Tulsa were NOT made for minis >.<*

Do not worry about getting a plate to check with, just take the head in and get it surfaced as it will need it because if you don't you will be doing it again.Some have gotten away with out surfacing but it's just a matter of time and they will be redoing the work.Also clean the block and sand it and the clean the bolt holes real good and i like to use Copper Coat gasket sealer on the threads as a lube for the head bolts.

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1978 pro street step/side 455Buick, 4sp,4.11s, 31/18.5s

Sorry about the late reply...

To check a head for warpage, you need a good straightedge and a feeler gauge.
I don't recall how much I paid for my straightedge (not a ruler, but a machinist's straightedge!), but a set of feeler gauges is only about $6...
And, yeah, you should check the block for warpage too... actually, I suppose it's not called warpage on the block. But definitely check that for flatness too.

Anything beyond .003" (aka, the feeler gauge with .003" printed on it shouldn't fit under the straightedge) is no good, and the head should be fixed.

I guess this is for future reference now, or is it fixed yet?
-ret

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1980 4X4 LUV daily driver, as stock as can be.

i've done 2 head gaskets in my truck... all i do is zip tie the chain to the sproket, put a 2x4 over the hood and cab and bungie cord the zip tie to the 2x4... undo the bolts lift the head up slip another 2x4 over the fenders but under the head long enough to remove the bungie cord from the head and you've got full access... the whole job takes about 5 hours start to stop ps be really careful not to drop the bolts down the front of the engine or move the crank shaft

Jake T

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Government... if you think the problems we create are bad just wait till you see our solutions

"Also clean the block and sand it and the clean the bolt holes real good and i like to use Copper Coat gasket sealer on the threads as a lube for the head bolts."

pretty likely I'm too late for this repair, but I'd very strongly suggest: DO NOT SAND the block's head surface!

All it takes is one grain of 'sand' to ruin a bore, and it may work its way to a bearing before the party is over. Even with a shop vac right next to sanding is no guarantee. Plus near impossible to get a true, straight surface with home brew sanding tools.

I would suggest instead to stuff rags tightly in bores, gently use scrapers suitable for removing any rust and then vacuum out bores while pulling rags out.