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Discussion Starter · #1 ·
So I’ve got a doozy here. I took my 03 into a mechanic to do the intake(no time to do it myself.) They did the job, turned it on for 5 minutes last night and it ran fine.

This morning they treid to turn it on and it wouldnt start. Long story short theres coolant in cylinder 3. They think that taking the intake on and off torqued the head such that it caused the old gasket to let go.

Has anyone ever heard of this before? Even the mechanics had never seen it before.

Their testing the cylinders, pistons, rods ect. for damage now. Theres no coolant in the oil, so its possible it leaked durring that quick test and overnight. I’m looking at 2400$ for head gaskets IF the motor is worth saving. What do ya’ll think? A motor around here ranges from around 2200-7k depending on the quality(used,remanufactured poorly to well). And apparently due to how everything is put together down there, the engine has to be dropped out the bottom with the trans attached. Which leads to an insane labor cost. That sound right?
I’m willing to put new head gaskets on there, I’ve taken very good care of it and its ran excellently despite its 210k miles. But a new engine?
 

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2000 Lifted 4x4 Astro 92 V8-350 Shorty
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$60 bought me a bottle of Blue Devil Head Gasket Sealant, which completely fixed my leaking head gasket. A year later... still good. A lot of excellent reviews. Well worth $60 to try.. in my opinion
 

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Uh, not a very likely scenario on their part. The intake manifold upper is plastic, the lower is aluminum and the heads are cast iron. If they even could torque the intake bolts enough to warp the cast iron heads then you are going to have even bigger problems. It is possible to have over torqued the intake cracking the intake casting, but you really have to twist those bolts to do that. Spec is only 15ft-lbs. No way that amount of torque on an aluminum intake could warp a cast iron head. More than likely is that the head and intake mating surfaces were not thoroughly clean and/or the gasket not installed properly. This usually results in leaks in cyl 1 and/or 2 because the water port is adjacent to those runners, but not 3.

Out of every Astro van I have owned or worked on over the last 35 years, I have never had one V-6 head gasket leak on it's own, unless overheated, but not on a normal use basis. I have heard the stories, but never have seen one in my garage. Plus, if it leaked enough coolant to hydro lock cylinder #3, that's got to come from somewhere substantial. Highly doubtful running it for only 5 minutes and then letting it sit all night caused that. More than likely after repair, it was run without coolant which warped the head and/or failed the gasket.

To replace the motor, dropping the engine/trans out with the cradle is the only way to do it and it sucks. You can unbolt the subframe, tilt the body off and crane it out that way, but that sucks as well. Never ceases to amaze me that any time a mechanic or shop performs a service and you have a new problem magically manifest itself before you even get it back, which has never occurred before, "It must have already been there or was on its way out."

Easy head gasket test is to pressurize cylinder #3 with an air hose on compression/power stroke (both valves closed) and look for bubbles in the coolant/radiator.

The key being that you state it ran excellently, until the intake gasket!! (makes me suspicious about the repair)

However unlikely, if that truly is the case and you like with the van, spend the money on the top end and enjoy it for another 100 thousand, miles that is.

Good luck and keep us posted.
 

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Discussion Starter · #4 ·
Yeah thats what my thoughts were as well…. how the hell does torquing the intake make the head even move?? They said something to the effect of when removing and then putting the intake back on, it causes a very small amount of movement in the head, combined that with an old head gasket and it broke the seal around #3. And only 3, all the other cylinders and the oil itself is fine. This is just their theory, and they stressed they really arent 100% sure what happened. Does that sound right to you?

I forgot to mention they did run a pressure test in the morning that showed a serious leak somewhere, could most of the coolant in the cylinder could have come from that test?
They did the 5 minute run after the van was totally put back together and the coolant refilled I believe. And I’ve never overheated it more then 5-10 degrees, and only twice in a 5 year time span, so IDK.
I’ll know more tommorrow when they get a look at the intake and heads themselves…. who knows
 

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Yeah thats what my thoughts were as well…. how the hell does torquing the intake make the head even move?? They said something to the effect of when removing and then putting the intake back on, it causes a very small amount of movement in the head, combined that with an old head gasket and it broke the seal around #3. And only 3, all the other cylinders and the oil itself is fine. This is just their theory, and they stressed they really arent 100% sure what happened. Does that sound right to you?

I forgot to mention they did run a pressure test in the morning that showed a serious leak somewhere, could most of the coolant in the cylinder could have come from that test?
They did the 5 minute run after the van was totally put back together and the coolant refilled I believe. And I’ve never overheated it more then 5-10 degrees, and only twice in a 5 year time span, so IDK.
I’ll know more tommorrow when they get a look at the intake and heads themselves…. who knows
We lost our one family owned 60000 mile 2002 malibu to this something like this. Had a shop change the intake to correct a vacuum leak, ran fine for the 150 mile drive home then the next day it had a hydro locked cylinder that was full of antifreeze. Took it back and they took it all apart and destroyed it then they went out of business and lost the shop. We went and got it with a trailer from the back lot. Trunk and back seat full of destroyed engine all taken apart with a bunch of broken parts. The new battery, most of the exhaust and one head were missing. Back seat destroyed.
 
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Discussion Starter · #6 ·
Damn dude! That sucks, sounds like some shiesty shit.

Update on my situation:
They took the heads apart and the headgaskets were actually fine. After much searching, the cylinder had a hairline crack down its entire length. I talked with the techs for a while and none of us could come up with any reason exactly why this happened. Perhaps the crack had been there for a while and something pushed it over the edge? It’s just so odd that it happened over night.

I’m looking at 7500$ for a new motor, most of that is labour due to the stupid engine removal procedure. And thats assuming they dont have too fight 19 year old frame bolts for hours on end. Me thinks it’s not worth it. Buuuut the resell value of a built out conversion with a remanufactored or sub 100k engine… hmm
 

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I guess prices could have gone up that much but who knows. I had a brand new GM original crate engine put in my 97 Astro (AWD) when I spun a bearing at about 180K (about 7 years ago). The total cost including labor was about 5500. Was totally worth it to get another 100k out of the vehicle.
 

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Discussion Starter · #8 ·
engine prices arent horrible, 2 and change for used low mileage, 3-4 for remanufactored. Problem is I happen to be in a , shall we say, high cost of living area atm lol. Labour costs are on the high end So 20+ hours of labor to drop the subframe out is where that # is coming from. If It was 5k I would already be doing it, but 7.5 is the cost of a new van lol
 

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My 95 had no issues with the subframe bolt removal and it's from Michigan. I would also be questioning the shop. I found subframe removal fairly straightforward.
 

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Discussion Starter · #12 ·
Nah their right on this. They performed a leak down when they got the heads off and saw that the gasket was still good. I inspected it myself, obvious single crack running down the cylinder.

For those that have done it, how many hours would you say is reasonable for the job?
 

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It's impossible to do a leakdown test if the heads are off. Also, the gasket is destroyed when removing the head. A large failure would be visible, but a small, new leak might not be. Speaking of heads... they don't move once they're torqued, and certainly not by installing an intake manifold. I'm wondering if there wasn't a coolant leak into #3 with the new gasket installed. Either way, you say there is now a visible crack in the cylinder. If there's coolant in the cracked cylinder, how did it stay out of the oil? How does the #3 spark plug look- signs of anything out of the ordinary?

Something sounds off here. The trouble is that the damage is already done and there's no 100% certain way to chronicle the chain of events.

I replaced the engine in my van through the front. I cut the core support and made brackets to put it back together. There is no way I could get away with (or have safe means to) drop the subframe and roll it around in my driveway. It can be done, and was the way to go in my situation.
 

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Discussion Starter · #14 ·
the heads were reinstalled for the leakdown. As I mentioned, the car was test run for ~5 minutes after the intake job, and then wouldnt start the next day. So the coolant didnt have time to circulate I’m assuming. The old gasket was old ofcoarse, but the offending bank still had a solid seal around all the cylinders, no signs of damage or leaking.
The tech said there can be movement by fractional amounts because the intake is at a 45 degee angle to the heads, IDK, doesnt sound right to me either but he said you can actually get a feeler guage in there. Either way, that clearly wasnt it. As the gaskets were fine. Something either caused a crack or caused an existing crack to finally break thru.

I’ll take a look at the plug after the weekend, I glanced at a couple yesterday and they were a bit sooty, but I’ve been running rich from an exhaust man. leak I’ve been lazy about fixing.
 

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Discussion Starter · #15 ·
I’m interested in the cut the core support method. It would save alot of labour and the mechanic isnt 100% opposed too it. Does it compromise the integrity of the support at all if bolted correctly?
 

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1992 Astro - Silver / Gray / 4 Wheels
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There are quite a few threads / posts here on the forum, some with fine pics, that address Gen II engine removal after cutting the core support.
If a Gen I is available - check out how GM did the 'removeable' section.
5Ps apply here - making the sheetmetal patch pieces, marking, cutting, paint/surf prep & protection are all 'key'.

I have wondered in the past if the part ( center horiz bolted portion of core sprt. ) pulled from a Gen I could be adapted somehow... just a thought.

The other keen point they always said was keep the 'hook' up tight to the engine puller arm.
 

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Gah! My reply was eaten. I'll make another post where it can be found by those looking for this info later, but the short version is bolt in is fine, it's how the older vans were built. No, we can't just bolt in a center section from an older van, I tried. It is shaped differently, and the location of the hood latch is different. I chopped up the center section I bought to make brackets that fit and looked better, the donor section I bought is the same color as my van. I worked with what I have on hand, stores are closed today. Film at 11:00.
 

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Discussion Starter · #19 ·
Based on the pictures I’ve seen online, the Gen 1 is bolt is oriented differently that it would be with this mod, so the forces are coming from a different direction which is what concered me. But its not like this is a serious structural support, little weight is on it, and unless I hit a tree its not having to resist movement.
And yes, concidering how many posts there are of people doing the exact same thing, if it was prone to fail I think we would of heard about it lol.

Big_kid
Do you mean you used cut out sections from the gen1 support to make a bracket for the genii?
 
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