Overheating after New Intake gaskets..?

[BattelWagun]

Hey everyone,

Ive spent the last week and a half laboriously and meticulously replacing my intake gaskets. I replaced them with a nice fel-pro set. After that i changed the oil after washing the valley with a quart or two to get all the debris out, etc. Well now I have her all buttoned up, so I began to flush the radiator. I thought I had it full of water (not coolant) and buttoned it up and started her, started right up (I have a feeling my timing might be a hair off). It idled for about ten minutes before overheating, so i tried to see if any air bubbles are in the system, I squeeze all the hoses etc. and nothing. Add a little more water and it still overheats, so now i decided to take the thermostat out. Did that, reflushed, and it got a hair past running temp after about 10 min of idling and 15 min of driving, I stopped there because it shouldnt get anywhere near that hot without a thermostat, right? Anywho, I unplugged the rad drain and put the hose in the top on full blast and started it, never even warmed up after 20 min!!!

Im lost! any help?

*also as a side note*- i dont have my fan shrouds on, i didnt think it would affect anything. no CEL or codes either

 

[Dpsthomas]

Did you check the water pump?

 

[AtomicHoe094]

Ive heard of people doing these gaskets before and having the same problem as you.. Sounds like you put the gaskets upside down or flipped or something causing to block the water passages?

 

[BattelWagun]

The water pump seems okay, or there is nothing leaking from it at least. As far as the gaskets go, the are reversible, there isn't a specific gasket for either side and they cant be flipped upside down because the little alignment lugs on them wouldn't work... I'm thinking an air pocket in the cooling system? I'm pretty sure its all good though...

 

[AtomicHoe094]

what temp is considered "overheating"? must be one hell of an air pocket. lol

 

[BattelWagun]

Well with the thermostat, all the way to the red, and without it, about 240 ish if I let it run that long...

 

[AtomicHoe094]

 

[BattelWagun]

yeah.... I am TOTALLY lost here, I mean i know quite a bit about these things, but i just cant undertsand how a completely free flowing system would overheat like that, even with water.... anyone else have any ideas?

...maybe ill tighten the intake bolts a little more...

 

[SunlitComet]

side note- PUT THE SHROUDS BACK ON and try again.
Your air probably sucking air from the sides and front of fan and not physically forcing any thru the radiator.

Could not see from your gasket set anything that could go wrong from incorrect placement.

Didi you have your heater on to bleed air out of everywhere? And when it was hot did you have a stiff upper hose?

 

[AtomicHoe094]

i wouldnt see the shroud having too much effect, shit people can use one single electric fan without shrouds and be fine :/

 

[BattelWagun]

side note- PUT THE SHROUDS BACK ON and try again.
Your air probably sucking air from the sides and front of fan and not physically forcing any thru the radiator.

Could not see from your gasket set anything that could go wrong from incorrect placement.

Didi you have your heater on to bleed air out of everywhere? And when it was hot did you have a stiff upper hose?

Alright man I'll put em on dont hurt me dont hurt me! haha

and yeah heater was on, I had the heat all the way up and the fan on low (haynes said fan on low so im trusting them...)

and yes the upper hose felt pressurized and was quite hot, i never shecked the lower though. I'm seriously considering taking it to a steep hill and parking it radiator up and seeing what happens...

 

[ezdaar]

Dude, you flipped your gaskets and blocked the crossover pasage.

I did the same thing once... Had tomany "man its hot grab me a beer" breaks during the install.

Sucks to hear, TRUST ME I know! but pop that mani back off and flip those gaskets, then laugh.

Exact same symptoms I had fire truck up, start cruisin, 10 min and your temp is redline...
No matter what you go... overheat...
flip those gaskets, bud...

 

[BattelWagun]

you gott be porkin me dude...

F*CK!!

EDIT: Wait, the crossovers are at the front and rear of the engine right? Because Those aren't blocked, I bought another set and compared it to my stock set, and all 4 gaskets are EXACTLY the same....

 

[SunlitComet]

fan on low is fine. The ideal is to make sure the water valve is open but not have to heat up you and your cab on a realy hot valve. When I first got my tahoe I always heard water pouring into the heater core like it had air in there some pouring water into a cup. I went away after I flushed out my system and refilled it in a specific way. I actually had the t-stat housing removed and filled the radiator till I was less than 1/4 below mounting face then put in t-stat and housing. after which I filled it more bleeding out as much of the in the top hose as I could. even flexed the hose to help the air ride itself out because of high section of hose. I did this because our t-stat were double valves with no bleed holes and I wantto to make sure the wax cartrige was submerged in coolant first instead of waiting for steam from an air pocket to do it. I had a good drop in average temperature afterwards.
never did the gaskets yet but will soon since my right cylinder head has to be removed.

 

[retorq]

Those plastic based reusable FelPro intake gaskets can NOT be put in backwards, not only that, they are completely symetrical so if you swap sides everything lines up perfectly.

You more then likely didn't hook up the bypass line to the water pump right.

 

[SunlitComet]

When i went back to look at gaskets again and I did find something odd some have small holes between the intake ports where other are large squarish cut outs instead of small holes. I think I am going to call the manufactures and ask about this.

---------- Post added at 02:36 PM ---------- Previous post was at 02:32 PM ----------

On eof the ones show by felpro is the one below with square cut outs so why the difference between this one and the one above?

 

[BattelWagun]

Sunlitcomet: you were right! I put the shrouds on and did mixed driving/idling for a good 20 mins and it never even got up to 210 (t-stat is still out) It did however get to about 160 ish, keep in mind though it's 89ºF here. So do you think I should go ahead and flush it again, put in the new t-stat (i got 195º, same as stock) and then fill with coolant? I have 5 gallons of autozones shit-cool stuff, I suppose it'll do fine with that.

as for the gaskets, you're right too, some have cutouts for ports which aren't on our vortecs. I believe it's so one gasket can be used for multiple engines. When I had my intake off, I actually noticed that those cutouts are on the block, but they are plugged.

 

[SunlitComet]

Just put the 195 degree stat back in after getting the level to the top in the manifold opening for the stat. bleed out best you can and try again. with it all back together. If it is the problem at least you would have not had to take it all apart again. If the coolant you just put in is still clean I would forget another flush right now. It usally take two complete hto/cold engine cycles for the sytem to bleed it self. On first cold start make sure your reservoir is at at or above hot mark. So as not to suck in air when it cools for first time. Second cycle cold engine jet make sure it is at the cold mark this time. If all go well you may only need minor reservoir adjustment for another cycle or so and be back to normal. Don't forget heater valve open till you are done.

See what happens.

I am gonna have to clarify this gasket difference before I start mine because I am getting a whole engine set so I i can do oil filter cooler mount and have some other if I need them later. That would be A $100 plus error for me.

 

[retorq]

The gaskets I posted are old school non Vortec/non crossover gaskets. I used it cause you can easily see they are symmetrical ... the large square cutout in the middle is the crossover, older heads had provisions the vortecs they are "there" but not machined.

If you look at this pic:

You can see that the cutout is in the gasket but they(FelPro) actually has a blank that goes in there to block it if it's not needed or going to be used ...

On eof the ones show by felpro is the one below with square cut outs so why the difference between this one and the one above?

After market heads and intakes use different sized water ports, you wouldn't seal up right if your head had big openings and you used the smaller opening gasket ... if that makes sense.

Sorry for the confusion.

 

[SunlitComet]

Still out there a little. So for my '96 vortec I need which one? the first one you posted or the one I posted because when I look at a replacement manifold I only see 2 square cut outs in the center of each side and the gasket has three squares Or Am i going to have to tear it down first. Kinda wanted to get everything on hand first.