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CenturyMan
09-18-2016, 04:43 PM
Has anyone on here ever removed both heads at ONCE after the went under and unbolted the main engine pipe going down to the rest of the exhaust system, and they left the rest of the engine cross pipe connected ? I have seen someone on youtube bolted everything up (exhaust and heads) put back on the engine in one piece but not taken off that way.

Duke George V
09-18-2016, 05:22 PM
You mean, unbolt both heads, the pull them by picking the whole shebang up by the crossover or something? Sounds feasible on paper. It'll be quite heavy though. The heads weigh around 35 lbs apiece. I'd be worried about cracking the crossover trying to deadlift that much weight. Not saying it can't be done, but I would advise against it.

CenturyMan
09-18-2016, 05:53 PM
It would be a two or three man operation , I have seen them put them back on the engine on youtube.com using two guys. They were working on a chevy venture van

Century7667
09-18-2016, 06:13 PM
Well, as long as you have a source for any exhaust parts you might break...otherwise, I'm with Daniel on this. One day you might have to take them loose, better sooner than later, and get some anti-seize on them. But, ultimately it's personal preference.

Ken T.

Keiths1976
09-18-2016, 08:32 PM
What I would do is disconnect the cross over pipe and take the heads off with the exhaust manifold attatched then on a bench soak them with pb blaster and remove the manifolds off the car . The age and all I would worry about breaking the rear exhaust manifold bolts . Front heat with exhaust manifold as one unit this way you can remove it . Also the torque specs on the exhaust manifold to head is low so don't go using bigger than a 3/8 drive I would use the 1/4 drive to install tho . The rear head is tight to get the bottom row with the firewall not saying it can't be done it's been done but if your pulling the heads off take the cross pipe off and take the pipe to the cat off the exhaust manifold and pull it up and out . The head bolts I would use a impact only there is one bitch bolt that's a t45-50 torx bit that's the ac bracket bolt through the front head . I used a 1/2 drive just for that with a 3/8 adapter and a long bar on my 1/2 ratchet cause it was stuck on and with pb blaster hope this helps Keith

CenturyMan
09-19-2016, 12:40 AM
An old time mechanic told me being the milage is so low 54k , I wouldn't have to do the heads over just pull them off clean up the engine deck with 80 grit paper clean everything up pop back on the heads

Keiths1976
09-19-2016, 03:08 AM
My one thing is that she was overheated there warped those head get a hot spot in the center of the block some old 3100 94-99 when the were over heated bad enough once you broke free the head bolts it would pop the seal soon as the bolts were looses (hence warped ) . Mileage has nothing really if the heads were driven with hot spots in the coolant jackets through the heads . There aluminum so it's possible they are or not . Just don't cheap out of it all that time and labor on your end to throw them back on and start leaking cause they don't seat right . I seen it done on the l82 it's not fun taking all apart and then sending the heads off to the shop and the gaskets usually are a one time usage so gets costly . Granted if it was a intake gasket failure or head gasket failure and no overheated was present or told . Coolant runs into the block and starves the heads from coolant and hot spots are created and burns up the headgaskets from heat and pressure .

Keiths1976
09-19-2016, 03:11 AM
Usually they shave the heads down to specs and remove tocmske them smooth and straight . Also another word to the wise on these engines remove from the center headbolts outwards So the stress is evenly spread out .

Century7667
09-19-2016, 05:44 PM
An old time mechanic told me being the milage is so low 54k , I wouldn't have to do the heads over just pull them off clean up the engine deck with 80 grit paper clean everything up pop back on the heads

Do the heads really need tom come off with only 54k on them? What is over heated badly?

Ken T.

CenturyMan
09-23-2016, 12:24 AM
I didn't do a compression test yet, I'm just guessing the worst. I know it's a pain in the ass to pull heads but I'm three quarters there already...am I being to crazy guys ???

Keiths1976
09-23-2016, 12:45 AM
Honesty man think of it this way . You do the work for the intake gasket and then worse you have to pull it all apart again . It's 20ish years old do it right replace the headgaskets and all the upper gaskets u can do . While your there and for a few dollars more do the timing cover gasket since it's all apart it's only a hour more job to do since it's basically apart as it is . In theory you will have a low mileage rebuilt motor gasket wise and drive it . All you have to do is remove the harmonic balancer it's not bad to do I had A huge screw driver wedged to stop the fly wheel from turning and take the center bolt off the harmonic balancer (is this all necessary or manitory to replace this gasket No but think about it it's a paper gasket which will fail eventually and leak coolant behind the alternator and if not notice you can kill all that work . ) it's cheap 12 bucks or less and clean up the area and check your timing chain while your there . The long run is your repairing all the stuff while your here getting her up to par and then enjoy it since you got it cheap it will be a daily driver and fixing all the little stuff if need to be

CenturyMan
09-23-2016, 05:27 AM
I've heard the timing chains are not the best.

Keiths1976
09-23-2016, 10:57 AM
Those are strong chains in the 3100 l82 if you were to replace it gm part only . People who have a newer 3100,3400.3500 from 2000 and up there upgrade timing chain is one from the l82 94-99 3100 . Those sir last long and durable as ever . Since she a baby with milage would check to see if there is slack on the chain trying to recall I think it was a 1/4 inch of play pushing the chain is good with a ruler I'm sure there is a better way of doing it by taking it off and having a new one compared to it . Did the same way to our old family 350 Chevy and was fine