Head Gasket Replacement

[Meyster89]

Square Body Down!!!!!! Parked my truck the other night, and noticed lots of dripping. Took starter off because that's where is was dripping, did a pressure test, and it is leaking, a lot, right under the head. Time to replace the head gasket. Now the fix seems simple, but looking for any tips or maybe if someone has a whole run down to make it goes a little easier. This is the first time I've done it and want to do it right the first time! Any advice will be greatly appreciated!! Thank you!

 

[MrMarty51]

Clean,make it clean,keep it clean.
Be sure to drain the prestone,especially from the engine block plug of the side You are working on.Preston is the very highest arch enemy of babbit in engine bearings.
I have never tried it but I have heard of peopledislodging the head without the removal of the intake manifold,I do`nt think I could or would ever try this on something of mine,just too much of a clean freak when it comes to gasket and mating surfaces.

 

[89Suburban]

Take a browse through here, lots of pics and opinions and info.

http://www.gmsquarebody.com/forum/showthread.php?t=1212&highlight=Head

 

[Driver4r]

I have never tried it but I have heard of peopledislodging the head without the removal of the intake manifold.

PAIN IN THE ASS, and its really hard to line the gasket up that way, theres not much room to play.

 

[HotRodPC]

Water coming from under the head? You sure it's not a rusted out or popped out Freeze Plug in the block behind the Exhaust manifold?

 

[Meyster89]

Water coming from under the head? You sure it's not a rusted out or popped out Freeze Plug in the block behind the Exhaust manifold?

The freeze plugs are good to go, checked them out as well. I saw it coming right out from between the block and head.

Thanks for the info guys!

 

[HotRodPC]

The freeze plugs are good to go, checked them out as well. I saw it coming right out from between the block and head.

Thanks for the info guys!

10-4 Just sayin, it woulda been a shame to pull the heads and then find out you didn't need to. Ask me how I know??? NO, it wasn't me. It was a neighbor years ago.

 

[chengny]

Any coolant in the oil? Loss of coolant or white smoke from the exhaust pipe?

A coolant passage to atmosphere leak - due to a head gasket failure - is unusual. There is no real heat stress in that area, pressure is limited to 14 psi (the coolant system pressure) and the width of the head gasket in that area is pretty wide. Generally there are other symptoms when a H/G fails.

Before you go through the hassle of a H/G job, when you pull the valve cover, it might be worth a minute to check the tightness of the head bolting.

If you find any bolts out of spec it , maybe consider backing off on all of them and then try to re-torque the head?

 

[HotRodPC]

Yeah you're right Jerry. It is very uncommon for a head gasket to go this way. In fact I was thinking he probably froze the motor wo antifreeze, and cracked a head or block. But then I seen he was in FL and that isn't the case.

 

[Meyster89]

Any coolant in the oil? Loss of coolant or white smoke from the exhaust pipe?

A coolant passage to atmosphere leak - due to a head gasket failure - is unusual. There is no real heat stress in that area, pressure is limited to 14 psi (the coolant system pressure) and the width of the head gasket in that area is pretty wide. Generally there are other symptoms when a H/G fails.

Before you go through the hassle of a H/G job, when you pull the valve cover, it might be worth a minute to check the tightness of the head bolting.

If you find any bolts out of spec it , maybe consider backing off on all of them and then try to re-torque the head?

...Damn it... haha. Ok, so I pulled everything apart, before seeing this, which shows that I need to visit here more often. The very back head bolt was indeed, not torqued down... and of course, it was the last bolt.. ... needless to say, the gasket was fine, and going back together, with new gaskets obviously.. BUT, the one thing I got out of this is I was able to properly identify the engine. When I bought the truck, I was told it had a newer 350 crate engine.... turns out, it actually has a 73' 307 with 4" bore with 416 - 305 heads, so i guess its a 327? I was wondering before anyways after I was getting 15mpg while driving like Ricky Bobby. Anyways, going back together, and going to save on fuel while I search for a 350 4 bolt block to build up. Thanks for the input guys.

 

[TX87R10]

Take a browse through here, lots of pics and opinions and info.

http://www.gmsquarebody.com/forum/showthread.php?t=1212&highlight=Head

Thread is gone unfortunately... This is a top search result so might be nice to point to an drive thread here.

Mainly pointing this out bc I was searching a similar topic and I have been trying to use the search feature better and it failed me here.

 

[89Suburban]

Thread is gone unfortunately... This is a top search result so might be nice to point to an drive thread here.

Mainly pointing this out bc I was searching a similar topic and I have been trying to use the search feature better and it failed me here.

I think it got moved, this should be it.

89S 350 TBI Head Gasket Replacement Project

89S 350 TBI Cracked Head Replacement Project Ordered the head gasket set today. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&viewitemversion=&item=260776955831&view=all&tid=767573852016

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