5.7 vortec water in cylinder??

hey guys,

i have a chevy 3500 express work van with a 5.7 vortec. i was all excited about my new work van this summer, so i did some prevenative maintanence on it.

the coolant overflow tank had some rusty dex-cool in it so i did a couple of coolant flushes. well i get my tools organiozed in it and start to drive it to jobs. steam coming out of the tailpipe, and its drinking coolant at an alarming rate. so its suckin coolant in somewhere and im leaving a cloud anywhere i go. longest trip .5 mile, all my projects are within a mile of my shop. so i parked it back in august.

im assuming its a lower intake gasket...these fail on vortecs i hear. so i finally got into it today. the starter isn't engaging the flywheel so i had to push onto the driveway. get the front end off. get the acc off. get the manifold off.

my oil is choc milk. #6 cylinder has standing water in the head above the intake valve. (i know my valve seats are good!) it also pushed some water out the left exhaust manifold when i turned it to TDC. my #6 intake manifold runner has brown slimy goo in it. all others are dry and look fine. #6 sparkplug is missing the electrode?

so here is my question. where is the water coming from? there are no water passages anywhere but on the front of a vortec intake manifold. it cant be a headgasket, or a cracked block the water is coming in above that. i assume its got a crack between the #6 intake runner and the coolant passage in the head? why would a coolant flush cause this?

i really dont wanna pull the head off to find its something simple i missed

ideas?

Intake gaskets/manifold. I doubt it is a HG's with 17 bolts holding the head down. But then again, it could be a cracked valve seat/bowl.

just so we're on the same page yere- the #6 cylinder is the second from the rear on the passenger side.

i don't know if there is a water crossover in the back of the intake manifold, but there is a water jacket in the head back there. the gasket could have failed there- but i can't see how the coolant would get into the #6 cylinder and not the #8 cylinder. look at the intake manifold- is there a big water jacket under the bottom of the entire intake manifold? i know the 87-95 TBI motors had water flowing thru there to heat the intake for better emissions and fuel economy, but i don't know if they did that with the vortec motors. if there is a water jacket there, look for cracks into the #6 runner.

the vortec heads are a light weight casting, and just like every other light weight small block Chevy head made since the mid 70's, they are prone to cracking and warping if they get hot.i think they usually crack between the water jacket and exhaust valve.

correct. #6 second from the rear passenger side.

there is no water jacket in the intake manifold except from left to right across the front. the rear of the manifold is actually solid where the rear water jackets 'should' the vortec heads have a water passage there, but it doesn't go into the manifold.

as far as i can see there is NO WAY water can get into the #6 intake runner untill the head. there is no water anywhere near it.

and again the water has been sitting in the intake port for a couple of months, so i know my valve seats and guides are good. but when it was running i could watch it drink coolant. so it has to be a large problem...not just a crack?

novaderrik wrote: i know the 87-95 TBI motors had water flowing thru there to heat the intake for better emissions and fuel economy, but i don't know if they did that with the vortec motors. if there is a water jacket there, look for cracks into the #6 runner.

thats what i assumed, and thats what has me baffled. i was excepting a cracked water jacket in the intake manifold. or a bad intake manifold gasket leaking between a water jacket and the #6 intake runner. but there is no water near any of the runners except for #1, and #2 up front.

Well.......two tools would have narrowed the problem area down without tearing it down, a vacuum gauge and a coolant pressure tester.

CPT would tell if you have an external or internal leak, won't hold pressure or you visibly see a leak, or if it were to hold pressure and not drop off, you could see it BUILD pressure from compression gases. The vacuum gauge could tell you the same thing, but more specifically where like which cylinder.

Looking at the above picture, the middle water port might have a path to the chamber from a leaking HG and filling the cylinder up.

Sounds like a cracked head. No big deal, just get another, they're cheaper than good dirt.

jon, check out the pic here: http://www.hotrodders.com/forum/attachment.php?attachmentid=31424

(i didn't imbed the image here because it's friggin' huge)

you can see both the #6 and #8 intake ports from the water jacket side of the head. IDK why it would crack there but probably a porosity / core shift / other casting issue that made it a marginal part from day 1.

found by googling "vortec head crack" and doing a little reading.

Don't buy into the "Vortec head cracking" debate. It is a wives tale that is just internet myth. The debate started because some moron noted that the Vortec head deck surface is only 1/4" thick... the same as the oft-maligned -624 smogger head that DID always crack. That person was comparing a light-weight casting with a lot more water jacket voids than the Vortec. The internal structure of the water jackets on the Vortec provides tons more rigidity than you would think. Put it this way... I've owned 6 sets of Vortec heads (both -062 and -906) and despite running two sets at well over 500 hp, one set in a 300-hp boat engine, and various other sets on other projects, I've never had a single one with a crack in it. I've blown a few head gaskets, but a cracked block or cracked head is the last place I'd look on a Vortec.

Vortec heads do not crack any more than any other chevy heads... which is almost never.

Water in #7 or #8 I can see possibility of the common intake gasket leak. Water in only #6 means head gasket or crack... but the chances of a crack are slim. Most likely head gasket.

P.S. Dexcool = satan. Flush it out and use plain green stuff. Do a google on it.

curtis73 wrote: P.S. Dexcool = satan. Flush it out and use plain green stuff. Do a google on it.

Very heavily agreed. It's like RTV. Completely evil stuff. You have to pick it out with pliers.

Don't buy into the "Dexcool = satan" debate. It is a wives tale that is just internet myth. <--- that's me pulling your chain, curtis.

even if the cracking situation is horribly overblown, the possibility of core shift in the casting process is still quite realistic, and the wall thickness between intake port and water jacket is certainly thin enough to spring a leak. Head gasket does not explain standing water in #6 intake port.

and before i forget, jon -- the missing electrode certainly prevented a hydrolock situation on that cylinder.

WELL, i removed both heads and took them to a machine shop. both sides cracked. the #6 was cracked on the exhaust side BAD, he said it would leak so bad it was filling up the cylinder, then the piston was 'pushing' the water up the intake port. one of the worst cracks he's seen.

my #8 was cracked too, exhaust side. the other head had a small crack between valve seats in #5.

so im lookin for a good set of heads. these things are not cheap or easy to find. everyone and their brother wants em for that 'racecar'

i did find a brand new GMPP set on CL for $500, or i can get a rebuilt (welded) set for $400 plus my cores.

curtis73 wrote: Vortec heads do not crack any more than any other chevy heads... which is almost never.

both the machine shop and the junkyards said all they see is cracked vortec heads. all the same, around the exhaust ports. showed me a pile of em.

so poo on you...

jhaas wrote: so im lookin for a good set of heads. these things are not cheap or easy to find. everyone and their brother wants em for that 'racecar' i did find a brand new GMPP set on CL for $500, or i can get a rebuilt (welded) set for $400 plus my cores.

Dude, you are saying that instantly finding a brand new aftermarket set of heads in your local Craigslist for $500 isn't cheap or easy? Do you want someone to bring them to your house and install them for you for free? Those heads are among the cheapest heads to buy. Ever.

good point...i did find them as low as for $50 each at a salvage yard...but i had to pull em and who knows if they were good. i've seen good used heads for $250-350 but i needed them NOW. i just picked up the $500 heads. still in the GMPP boxes!!

it just feels like a waste on a work truck!? i've never spent that a head for any of my 'fun' projects. maybe i need to stop tryin to make all my projects fit into a $200x budget?

jhaas wrote: WELL, i removed both heads and took them to a machine shop. both sides cracked. the #6 was cracked on the exhaust side BAD, he said it would leak so bad it was filling up the cylinder, then the piston was 'pushing' the water up the intake port. one of the worst cracks he's seen.

good explanation for the skanky goo you found in the intake manifold too.

jhaas wrote: good point...i did find them as low as for $50 each at a salvage yard...but i had to pull em and who knows if they were good. i've seen good used heads for $250-350 but i needed them NOW. i just picked up the $500 heads. still in the GMPP boxes!! it just feels like a waste on a work truck!? i've never spent that a head for any of my 'fun' projects. maybe i need to stop tryin to make all my projects fit into a $200x budget?

Most people spend close to that on a car payment IN A MONTH

jhaas wrote: WELL, i removed both heads and took them to a machine shop. both sides cracked. the #6 was cracked on the exhaust side BAD, he said it would leak so bad it was filling up the cylinder, then the piston was 'pushing' the water up the intake port. one of the worst cracks he's seen. my #8 was cracked too, exhaust side. the other head had a small crack between valve seats in #5.

Jon, that's internet myth! Just put those heads back on, they'll be fine!

Sorry Curtis, but I work at a salvage yard, and we sell Vortec 350's for $1,000 exchange faster than we can get them. And IF the core has good heads (and that's a big if), we sell them for $100 each, and they're usually gone within a week. They crack. It's a fact.

16vCorey wrote: we sell Vortec 350's for $1,000 exchange faster than we can get them. And IF the core has good heads (and that's a big if), we sell them for $100 each, and they're usually gone within a week.

Dang, that's not cheap at all. In 2003 I bought one (from JmfnQuasiCamacho) for $200 from oil pan to intake. I pulled the heads and bolted 'em onto the 327 in the V8Vair and gave the shortblock and intake back to him. and in '08 i bought one that already had an Edelbrock manifold and carb on it for under $500. i hope to see that one at the challenge someday, as it went to someone we all know and love.

AngryCorvair wrote:

16vCorey wrote: we sell Vortec 350's for $1,000 exchange faster than we can get them. And IF the core has good heads (and that's a big if), we sell them for $100 each, and they're usually gone within a week.

Dang, that's not cheap at all. In 2003 I bought one (from JmfnQuasiCamacho) for $200 from oil pan to intake. I pulled the heads and bolted 'em onto the 327 in the V8Vair and gave the shortblock and intake back to him. and in '08 i bought one that already had an Edelbrock manifold and carb on it for under $500. i hope to see that one at the challenge someday, as it went to someone we all know and love.

Yeah, I know. They've actually gone way up in price now that they've got some age on them. Lower supply and higher demand I guess. A few years ago we sold them for $500 exchange.

OK so im gonna reuse the stock head bolts (what a shock) what should i torque them too? im findin numbers all over the place. i assume i need to use sealant on the ends? these holes go into the water jacket right?

also i've used 'copper coat' on every head i've ever done. any objections?

In reply to jhaas:

i never put anything on the deck surfaces of the block or the head. a little RTV around the water passages on the intake surface of the head.

if the head bolts go into a water jacket, then i put some RTV on the bolt before dropping it in.

google will be your friend on the bolt torque, but for some reason 65 ft-lb is jumping to the top of my memory.

jhaas wrote: OK so im gonna reuse the stock head bolts (what a shock) what should i torque them too? im findin numbers all over the place. i assume i need to use sealant on the ends? these holes go into the water jacket right? also i've used 'copper coat' on every head i've ever done. any objections?

you only need copper coat if you are using thin steel shim head gaskets. any other gasket that has any sort of a coating gets put on dry. they are just regular small block Chevy head bolts, so i think it's 75lb ft on the long bolts and 65 on the short bolts.

there is no need for any sealer on the intake gaskets, except for the 1/4" bead of ultra black rtv or (preferrably) "The Right Stuff" out of the squeezy cheez can along the front and rear "China walls" on the block. the vortec intake bolts only get tightened to something like 17lb ft.