Cracked vortech heads on a "new" engine?

[The Struggle]

Not to cause a stir and stress the OP with more variables, but here's my outside the box thought. Does the truck come with a transcooler in the radiator? I know ATF floats atop water, but would you guys think that that if a pinhole in the internal weld could expose the coolant to be sucked into the tranny? A dipstick check may be a quick resolved variable. Just trying to cover all other random leaks...

 

[crazy4offroad]

He would have ATF/coolant coming out the dipstick at this point as much water as he says is disappearing. Hopefully it's out the exhaust.

 

[77 K20]

Worst problem I've seen with running Vortec heads is intake gasket seal. The bolts are really wimpy compared to old school. Did you use any gasket tack or any kind of gasket dressing before assembly? Did you use the thick gaskets or the thin ones with the silicone seal? Have you noticed any steam out the tailpipe? To lose that much water, after it's warm you would think revving it would make water come out. I'm pretty sure you mentioned no water in the oil, vice versa, or bubbles in the radiator. If it's steaming at all (or moisture in the exhaust well after warm-up) it could be a leaky intake gasket. Have you run a vacuum check on it yet? Probably not going to be the best way to check for a vac leak if you're running a cam with any aggressive profile. You could try the propane trick. Put a piece of vac tube on a propane torch, turn it on low and while the truck is running put the tube around areas you might have a vac leak. If the rpm goes up there's a leak. Of course you could have a water leak and no vac leak. Goes without saying be careful using propane this way. You could try the UV dye and try to track it down, too. Just a few suggestions to look at. My '02 Sierra likes to drink water "sometimes" and I've never figured out why. But what you're using/losing is excessive that's for sure.

When I installed the first Edelbrock intake I used the GM plastic intake gasket (with the silicone seal). After reading about how the plastic can crack or melt after years I paid a shop to replace those gaskets. In talking to them and reading online it was determined that the thick ones (like what Edelbrock sells) wouldn't be the way to go. There are layers of their gasket and can sometimes separate causing a leak. Also they are so thick you need to keep re-torquing them. Instead supposedly the "best" gasket is made by Fel-Pro. Based on the GM design but instead of being made with plastic they are made of metal. This second gasket was installed by a shop. Still had a coolant loss.

With the new intake manifold I went with the metal Fel-Pro gaskets again.

On cold mornings I do see steam coming out of the pipe- but every other car I own had steam coming out their exhaust pipes at the same time. (the steam cloud wasn't any bigger...)

At idle I'm rock steady at 21" of vacuum. I still went over any edges, fittings and all over the manifold with starting fluid while idling. No change to the idle.

I haven't had much time to drive this- as my MSD ignition module on it suddenly fried earlier in the week. Had to wait for a replacement. Got it up and running yesterday and drove it for about 40 minutes. Checked coolant this morning and it was slightly lower than it was the day before. Looks like it is "using" about 1/3 the coolant as it did before the manifold replacement? I'm going to keep driving and keeping an eye on it.

Driving it is getting more challenging also. My Edelbrock EFI has been running worse and worse the last few months. My current theory is the burning off of antifreeze is screwing up my O2 sensor. It surges while idling bad- so bad it will often cause the truck to stall. Once in gear and driving down the road it is better, but still surges when coasting. Not going to swap out the O2 till the leak is fixed.

I'll be taking a vacation tomorrow and won't be driving it. It's my 20th wedding anniversary and if I work on the truck or bring it there won't be a 21st! (She hates my truck even when it was running well).

 

[crazy4offroad]

If an intake/gasket change made a measurable difference there has to be a link. And there will be 21st.

 

[77 K20]

Ok, so I've driven this truck everywhere for the last 3 weeks. It doesn't use coolant- as I haven't had to add a drop.

So somehow my old manifold had a crack or perhaps a bad casting allowing coolant to escape after heat cycling.

Now I need to send it back to have Edelbrock examine it and hopefully they find something. I want my money back for that manifold since I had to go buy a second one.

 

[crazy4offroad]

Good to hear an update on this. Hopefully they find an imperfection and not try to pass off the blame on the intake manifold gasket. Be sure to post back what you hear from them.

 

[HotRodPC]

Ok, so I've driven this truck everywhere for the last 3 weeks. It doesn't use coolant- as I haven't had to add a drop.

So somehow my old manifold had a crack or perhaps a bad casting allowing coolant to escape after heat cycling.

Now I need to send it back to have Edelbrock examine it and hopefully they find something. I want my money back for that manifold since I had to go buy a second one.

Glad to hear the mystery solved, at least for the most part. I really had my doubts the heads were cracked.

 

[Jim Hensley]

400 bucks to install intake gaskets ? , **** me I want to be your new mechanic.

 

[77 K20]

That's what all of the shops around here charge. Some wanted almost $500. And since I typically spend 33% of my time on the road with my job I'll be damned if I'll spend all my home time working on this truck.
I have done a ton of work to it in the past- I just need something I can drive now without screwing with it every other day.

 

[Jim Hensley]

that is insane, its like 400 bucks an hour labor rate

 

[77 K20]

So I've driven this truck everywhere for 2 months. Things were going good. I decided I needed to upgrade the alternator- as it is cold and rainy here. My alternator can't keep up at night with the headlights on, fan on high, and wipers on.
Opened the hood to check out a few things and... COOLANT IS LOW!!!! It is like one of those re-occurring nightmares.
This time I pulled off the TBI and shone a flashlight down into the intake manifold. It is wet and glistening. The waffle pattern in the intake manifold has green fluid along the edges. I dropped a white paper towel down in there to soak up some. Yes, antifreeze. So yet again the second intake manifold now somehow has coolant creep/soak/float up thru the manifold and into the intake path.
What the ****?
So now I have 2 bad Edelbrock manifolds sitting in the garage and a truck that uses coolant everytime it cools off. I had to add 400 mL to bring it back up to full.
Dumping more money into it isn't a possibiltity right now. Work screwed me over and dropped by pay by $6,000 a year. 3 weeks ago my water heater rusted out and flooded the basement. Have those bills to pay. The TDI had it's high pressure fuel pump die... and yesterday my tooth broke apart. So I'm broke for the next 6+ months. I'm getting screwed by anything/everything right now.

Anyway... what to do?

1)The coolant is only going into 1/2 of the dual plane manifold. Seems to be roughly 80 mL of coolant for each time I drive it. Will this ruin the new engine long term? (Ignore this POS issue and just drive the damn thing).
2) Bitch to Edelbrock again who says this cannot happen and try to get another intake manifold and try for a THIRD time. I would have install costs for this ($400)
3) Remove the coolant lines that go below the TBI and figure out a way to use stainless lines to plumb exhaust thru the manifold like the old small blocks. Without heat in the manifold it won't run worth a **** in the fall/winter/spring.
4) Park it and save up for non vortec heads. Buy old school heads and old style intake with exhaust crossover. $3000 probably.
5) Ditch the POS intake manifold and the TBI setup and buy a multi-port fuel injected intake manifold. Since this is a dry intake manifold setup no heat is needed. Roughly guessing $3,000.
6) Give up and sell it. Will take a massive loss. Have well over $10,000 easily in the last few years into it. Body looks like a $800 truck.

 

[Green79Scottsdale]

Will you post some more pictures of your current set-up? From both sides of the vehicle and some closer shots of all the connections that have coolant flowing through them.

Just thinkin' out loud... Have you checked the torque of the intake bolts? According to the instructions they only require 11 ft/lbs. If they are not tight enough, you theoretically could get a leak. If they are too tight, you could distort the sealing surfaces and theoretically get a leak. This leak started with the GM gaskets correct? That's why you went to the Fel-Pro gaskets? Does the throttle body itself have coolant going through it?

 

[crazy4offroad]

First thing that popped into my mind while reading it was, is it possible something like a heater hose fitting is being over-tightened when installed? Or the casting is very weak. I am dangerous with plastic and aluminum things so don't take the comment personally. I break fragile **** all the time. Since it is appearing only in one half of the dual plane for some reason that was the first thing to pop into mind.

 

[77 K20]

The first manifold was installed twice. First with GM plastic gaskets, the second time with the upgraded metal ones. I torqued the bolts to 11 ft/lbs. Not sure what GM dealer did to the new one. They should have also done 11 ft/lbs as it is their design.

On the second manifold I used brass fittings to make sure I didn't overtighten and brass has a better seal than stainless (which I used the first time).

Doesn't look like much perhaps. It does in person. This was inside the manifold itself after letting it cool off overnight. It is a dual plane intake so this is the side on the driver's side. (the lower level of the manifold). It would be the one right next to the coolant plenum underneath. Manifold is wet. I used a white paper towel to dab at it. Paper towel was then green.

I just called Edelbrock and said it must be a "porus issue" with both manifolds but want me to pressure test them. I said I've already done that. I couldn't get it to leak with air pressure. It only seems to leak when the temperature is changing. I can't verify if it leaks when heating up, but obviously it continues to leak after the truck is turned off.

They still want me to pressure test it. AAARRRRGGGGG!!!!!

I asked what they thought if I just hooked it up to exhaust. They put me on hold and came back with: NO don't switch to exhaust. With a possible defect in the casting it could result in unregulated EGR action which would cause a dangerous lean condition on the cylinders and could ruin the engine. I was hoping even if it leaked a bit hopefully it would carbon up and plug its own holes. Or if it leaked when the truck was off and cooling off I wouldn't care.


My last thought at a cheap "bandaid" fix is to put a restrictor inline with the heat plenum. Right now it is just wide open 7/8" silicone heater hose. If I choked it down on the inlet that should drop the pressure after the restrictor and maybe it wouldn't leak? Or at least leak as much?

 

[77 K20]