New to me 99 Suburban: 5.7 vortec repairs

NevadaLover

Forking Icehole
oh that sucks, make sure to watch your coolant level closely and put a couple miles on the truck, if the level drops then you probably slipped the gaskets! If the level doesn't drop then you probably got some coolant into the exhaust thru the heads no big deal it'll burn off eventually! You did use the correct fel-pro gaskets right?? the MS98000T set with permadryplus gaskets?? Hopefully you did, the alternatives suck and will eventually leak again!!
 

rayra

Expedition Leader
man look at the wear on those spark plug cathodes! Makes me afraid to pull my Tahoe's. I don't think they've ever been replaced. Yours or mine.


The smoke, that's a damned shame. I'd warm it up and do a compression check. Then I'd pull the intake manifold. Very likely you knocked the intake gasket askew when you set the intake manifold. If you're lucky.
 

unabashedpraise

Adventurer
So I checked it the next morning. No smoke or steam at all. None. Drove fine with no hesitation and no noticeable steam or smoke. I'm guessing it was just coolant and other contaminants in the engine and exhaust after sitting for a few weeks??

I'm midway through a coolant flush. I'll check for more steam tomorrow.


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rayra

Expedition Leader
That sounds like good fortune. Yes it could have been fluids spilled into the intake ports when teh intake was off. But it shouldn't have lasted very long at all. Or it got blown out into the muffler and hung around for a while.

Sounds like you about have it done, have some break-in / test time in mind, or you going for a trip first thing?
 

unabashedpraise

Adventurer
Man I am really really really hoping it's going to be good to go.

Going to drive it a few days to and from work, then a smallish trip to the lake this weekend.


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rayra

Expedition Leader
'well there's your problem right there'

Front left corner intake manifold gasket misalignment, sucking and blowing coolant from the crossover passage? If so that's going in your galley and oil pan too. But I've never seen it blow out the manifold like that. That from cooling system pressure at operating temp? And don't know how you even get the manifold bolted in properly if the gasket is that misaligned.

re-suggesting you put a compression gauge on at least the passenger side bank, before you pull the intake manifold.


/that is both sucking AND blowing
 

unabashedpraise

Adventurer
'well there's your problem right there'

Front left corner intake manifold gasket misalignment, sucking and blowing coolant from the crossover passage? If so that's going in your galley and oil pan too. But I've never seen it blow out the manifold like that. That from cooling system pressure at operating temp? And don't know how you even get the manifold bolted in properly if the gasket is that misaligned.

re-suggesting you put a compression gauge on at least the passenger side bank, before you pull the intake manifold.


/that is both sucking AND blowing
Actually, the intake pic is from the heater control valve hose blowing off. However, it was smoking from there tailpipe again, but stopped after a short drive. I used compressed air in the engine to try and blow as much coolant out as possible. Maybe it blew sooner into the exhaust?


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unabashedpraise

Adventurer
What I don't get use that I didn't have any steam coming from the tailpipe before I changed the intake gasket. How do I tell if it's intake vs heads?


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rayra

Expedition Leader
That's why I was suggesting the compression gauge, before you bother to take off the intake manifold. If you've got a head gasket leak, you might be able to tell by the PSI readings. And if you are still getting coolant into your cylinder chambers via an intake leak, you'll see that crap spray out the spark plug holes while cranking for the compression check. If your PSI numbers are all good and close, its a fair presumption the coolant is being introduced via the intake rather than a bad head gasket leak.

Get it otherwise running and get it and the exhaust good and hot. If it's fluid down the exhaust from the original breeching of the intake manifold, get it burned out and call it good. If it's STILL happening, still blowing smoke like that after it sits overnight, you're pulling it back apart again.

You MIGHT be able to see a difference in the plugs you pull for the compression check, if it is a head leak and only getting into one chamber.

And you'll want to change your oil again before you take it on any hard run or road trip. If you got a lot of coolant in your oil it might queer the lubricity enough to wind up with bearing troubles. Check your dipstick after a run for some 'chocolate-milk looking oil. Check the inside of your oil fill cap after it sits overnight (not much use in summer, but if it's chill enough you'll get condensation inside the cap overnight, if there's a lot of coolant in your oil.

One other question - did you drain your coolant system BEFORE you broached your intake manifold? If you didn't, that might account for a lot of coolant making it to your muffler. If you DID drain it down before you pulled your intake, then you likely have a real problem of some sort. And then you start by draining down your coolant and re-opening the intake manifold to see what happened with your gaskets. If anything. After you do a compression check.

Lot of this stuff is basic auto / engine mechanics. If you took on this project you likely know most or all of it already. But I'm putting it in here as much for the audience as for you.

good luck, fingers crossed that it's something minor / silly.
 
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unabashedpraise

Adventurer
That's why I was suggesting the compression gauge, before you bother to take off the intake manifold. If you've got a head gasket leak, you might be able to tell by the PSI readings. And if you are still getting coolant into your cylinder chambers via an intake leak, you'll see that crap spray out the spark plug holes while cranking for the compression check. If your PSI numbers are all good and close, its a fair presumption the coolant is being introduced via the intake rather than a bad head gasket leak.

Get it otherwise running and get it and the exhaust good and hot. If it's fluid down the exhaust from the original breeching of the intake manifold, get it burned out and call it good. If it's STILL happening, still blowing smoke like that after it sits overnight, you're pulling it back apart again.

You MIGHT be able to see a difference in the plugs you pull for the compression check, if it is a head leak and only getting into one chamber.

And you'll want to change your oil again before you take it on any hard run or road trip. If you got a lot of coolant in your oil it might queer the lubricity enough to wind up with bearing troubles. Check your dipstick after a run for some 'chocolate-milk looking oil. Check the inside of your oil fill cap after it sits overnight (not much use in summer, but if it's chill enough you'll get condensation inside the cap overnight, if there's a lot of coolant in your oil.

One other question - did you drain your coolant system BEFORE you broached your intake manifold? If you didn't, that might account for a lot of coolant making it to your muffler. If you DID drain it down before you pulled your intake, then you likely have a real problem of some sort.
I did drain the coolant before I started the intake. There was a little coolant in the valley under the intake, but not a lot.

I changed plugs before I started it up. Would I get much of a reading from them seeing how they aren't tarnished and worn yet? Same with the oil.


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rayra

Expedition Leader
probably not on the plugs, but if you pull the ignition and crank it some before pulling the plugs, one or more might carry signs of coolant when you pull them, helping to narrow down whether it's general or a specific cylinder.
And if there's a bunch in your oil you'll only really see it after it's run for a bit. The oil will get frothy and look a good bit like a chocolate milkshake. You might also pull the pan plug and see what drains out first, after it sits overnight. If there's a bunch of water it'll come out first. just take a couple paper towels and hold it under the loose plug, remove it for just a moment and screw it back in. You should see the evidence on the towel.
 

rayra

Expedition Leader
I'm sitting here looking thru some of my own old engine rebuild pics, does your even have any coolant crossover thru the heads and intake? My old SBC in my C-10 didn't and my '02 has a sort of crossover plumbing pipes separate from the 'dry' intake, at both the front and rear edges of the block.
 

NevadaLover

Forking Icehole
What I don't get use that I didn't have any steam coming from the tailpipe before I changed the intake gasket. How do I tell if it's intake vs heads?
That statement basically answers itself, if the only difference is a replaced gasket then that is almost guaranteed to be the problem, if the gasket slipped or was damaged on installation it can allow the coolant into a cylinder, Rayra has a good point about the compression test but I would bet it is the gasket!! it sucks but sometimes this **** happens, the good thing is it will be easier to do it the second time! And make sure to use the felpro gaskets I posted earlier, any other gasket is an exercise in futility and they don't slip like the other type do!!
 

unabashedpraise

Adventurer
I'm sitting here looking thru some of my own old engine rebuild pics, does your even have any coolant crossover thru the heads and intake? My old SBC in my C-10 didn't and my '02 has a sort of crossover plumbing pipes separate from the 'dry' intake, at both the front and rear edges of the block.
Honestly I wouldn't know. Could my pics in this thread help?


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