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Have any of you had recurring problems with blown head gaskets. I've had the head checked followed the proper torque sequence's and still blow a head gasket about every 8 months, any help would be appreciated

Does the gasket blow at the same place each time? Maybe you have deck problems. Could try retorqueing after a few miles and see if that helps.

I agree. If the head has been checked and it's not warped...then it could be the block isn't right.

Check it with a good reliable straight edge to see the next time you do a head gasket replacement.

If they are both good...try a different brand of head gaskets and you should always re-torque the head bolts.

I do mine after the first 2 weeks or so...depending on how much and how hard I drive it.

If that doesn't solve it...you need a new torque wrench...lol

Sounds like Taz is right...either the head or the block is warped.

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'78 1.8L 4-speed Fleetside

The only thing more beautiful than a sunset is a sunrise.

I have run into the warped block several times and have machined a couple while working in a machine shop.This can be done without completely dismantling the engine if you pull the pan and wash all the oil out.You didn't say if you had the head surfaced but i assume that you have if so then it will be your block.There is one other possibility as remote as it sounds i have seen it,if the head has been way over heated or cooked i have seen the alum. loose it's temper(as little as it has) and be real soft letting it move around.

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

Every LUV that I have owned with head gasket problems, I have found the block to be the problem. It pulls up and distorts around the head bolt holes. Have it planed. I believe it is caused by too high factory recomended torque settings. I torqued the head to 55-60 lbs instead of 70 lbs. Never any more problems. This is what many Nissans, Toyotas, Hondas, etc with alumunum heads called for. Worked for me.

What tolerances are acceptable on the block surface

That depends on how much you like to throw wrenches at your own truck.

J/K...lol

Factory spec's according to all 7 of the different manuals I have that apply to the luv or the G180 engine are no more than .007 of an inch is acceptable warpage for both the head and the block...and that is total combined for both - not for each.

But a thought just occurred to me...have you checked down in the headbolt holes to see if there is debris in them? I know someone that accidently dropped a few small screws down in his head bolt holes and it kept his bolts from tightening down the head when they were torqued.

Worse part of that was...it was his wife that figured it out...lol

Also...you might try replacing your head bolts, because they have been known to stretch sometimes. In fact, on some engines like the Suzuki 3-banger that comes in a Geo Metro...it is mandatory that you replace them with new ones every time you remove the head.

Hope this helps ya.

Well I haven't exactly taken it apart yet, but it is exhibiting the same characteristics as the last time it blew a head gasket. I'll let yall know as soon as I get it taken apart

Hey Egg, that's very interesting, what you said about the head torque, and my newly machined block and head will be joining sometime soon. That's a real interesting idea to lighten up on the torque, but how sure are you the steel block will give before the softer aluminum head?

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'78 1.8L 4-speed Fleetside

The only thing more beautiful than a sunset is a sunrise.

Similar story - different engine...
I've heard of engines where a little to much oil or water got trapped in the bolt holes... when the engine got hot the expansion created micro-cracks radiating out from the bolt holes from the pressure. True story. The BMW S-14 Engine (first M3 series) has seen this issue now that they are getting old and rebuilt frequently... spendy suckers, too.

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1978 shortbed fleetside, th350, Fireball 231 Even Fire V6, Edelbrock 500CFM Performer with Edelbrock intake. Workin' Truck.

That's why I tap them out and blow compressed air down the holes before placing the gasket and the head on.

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'78 1.8L 4-speed Fleetside

The only thing more beautiful than a sunset is a sunrise.

Fullaluv, I noticed that the block distortion was around the head bolts. Also when I planed the aluminum head that is where most of the material needed to come off first, around the bolt holes. So I would say that the two are being distorted together--the block and head-- at the pressure point of the bolts. Not conclusive I'm sure but I have a feeling that is going on. When the head is tightened down it bottoms at the distorted bolt holes. This leaves the rest of the gasket with not enough pressure like between the cylinders, water jacket holes, etc.
The last luv I owned--a 79 4x4-- lost the head gasket at about 50,000 mi.
After replacement it was still going strong when I sold it to my neighbor at 125,000 miles.
I am enjoying the step by step rebuilding process of your's. I can't wait for you to get it on the road again! Wishing the best for you!