Engine Coolant System Over-Pressurized??
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Joined: Dec 2001
Posts: 553
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From: Columbia, MD
Engine Coolant System Over-Pressurized?? I have a Vortech G-trim kit, 2.75" pulley, 370ci, heads & cam.
The aftercooler coolant system is totally separate from the engine coolant system.
Does anybody have a clue why the engine coolant system gets over-pressurized and keeps blowing coolant into the overflow reservoir can and onto the ground??
We are stumped.
The aftercooler coolant system is totally separate from the engine coolant system.
Does anybody have a clue why the engine coolant system gets over-pressurized and keeps blowing coolant into the overflow reservoir can and onto the ground??
We are stumped.
no combustion gas residue shown by the dye testing... 6-7 psi boost, 16 degrees of timing, headstuds, and 11.7 a/f max its ever seen. Doesnt lose ANY power, first pulls still same as now, coolant temp reading low to mid 180s max.
Randy said his old setup did this so they pinched off the coolant overflow line to slow it down... wasnt aware of that. Im wondering if there is somethign into a coolant jack into an intake port, and boost is seein it before the combustion cycle. Basically would be boost pressure doing it not cylinder pressure. Wondering if I take inlet elbow off and run NA to see if it still does it.
Doesnt smoke or anythign or show signs of burning any coolant
Randy said his old setup did this so they pinched off the coolant overflow line to slow it down... wasnt aware of that. Im wondering if there is somethign into a coolant jack into an intake port, and boost is seein it before the combustion cycle. Basically would be boost pressure doing it not cylinder pressure. Wondering if I take inlet elbow off and run NA to see if it still does it.
Doesnt smoke or anythign or show signs of burning any coolant
Originally Posted by Crunch
I have a Vortech G-trim kit, 2.75" pulley, 370ci, heads & cam.
The aftercooler coolant system is totally separate from the engine coolant system.
Does anybody have a clue why the engine coolant system gets over-pressurized and keeps blowing coolant into the overflow reservoir can and onto the ground??
We are stumped.
The aftercooler coolant system is totally separate from the engine coolant system.
Does anybody have a clue why the engine coolant system gets over-pressurized and keeps blowing coolant into the overflow reservoir can and onto the ground??
We are stumped.
I knew there was something I wanted to ask you this year Mike. 
So you've been using MLS hg's all year, so when you push some water, do you run the car with the same gaskets, and/or do you retorque the studs? Wondering what your rule of thumb is.
So you've been using MLS hg's all year, so when you push some water, do you run the car with the same gaskets, and/or do you retorque the studs? Wondering what your rule of thumb is.
Originally Posted by TwnTrboCE
Welcome to pushing water. How many passes on the gaskets? What gaskets? What pressure rad. cap?
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Originally Posted by GrannySShifting
they do it at only 7 psi, and from a few dyno pulls only. I havent had this problem on a stock longblock stock gaskets/bolts up to 14 psi
John,
MLS gaskets. No retorque. Just drain the overflow and add water back to the radiator. I'll run the same gaskets untill I see the bottom of the head where it meets the block turns black. Or if it starts pushing more water. Or if it's been so long I just want to see what things look like. Last season with my LS2 motor I changed the gaskets one time.
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Verdad Gallardo head was supposedly checked/deck at machine shop... but did I see him do it no. Id have to assume it was done. Cracked, possibly, he said last combo did it. I was wondering if it doesnt smoke because positive manifold pressure keeps it from entering the cylinders
I changed my gaskets when, like Mike said, I started seeing black marks on the outside of the head/block.
But at 8-9psi I never had a problem like that at all so something is wrong, but if you arent getting any combustion in the water I doubt its head gaskets. After about 20 passes my coolant smells like exhaust. Unless there is a crack or something in the intake port thats pressurizing the coolant but I doubt 8psi would do that, caps are rated at 18psi and you would think it would push water back into the port if you pressurized the radiator overnight,
But here is something I found, if you are using an aftermarket radiator cap (stant in my case) the water will never get sucked back into the radiator when it cools off and the radiator always seems 'empty' but the coolant overflow kept getting more and more filled since I kept adding water to the radiator. My stock cap was blowing a little out of it on a pass so the first thing I did was put a cap from NAPA (stant) on it and that stopped but it also stopped pulling coolent back in from the bottle when the car cooled off. Just for the heck of it I bought a new Delco cap (RC24) and now the radiator always stays full, lot of aggravation for 8.00 lol. The delco cap has some kind of valve on it the stant didnt and I assume the closed setup doesnt work right with it for some reason.
But at 8-9psi I never had a problem like that at all so something is wrong, but if you arent getting any combustion in the water I doubt its head gaskets. After about 20 passes my coolant smells like exhaust. Unless there is a crack or something in the intake port thats pressurizing the coolant but I doubt 8psi would do that, caps are rated at 18psi and you would think it would push water back into the port if you pressurized the radiator overnight,
But here is something I found, if you are using an aftermarket radiator cap (stant in my case) the water will never get sucked back into the radiator when it cools off and the radiator always seems 'empty' but the coolant overflow kept getting more and more filled since I kept adding water to the radiator. My stock cap was blowing a little out of it on a pass so the first thing I did was put a cap from NAPA (stant) on it and that stopped but it also stopped pulling coolent back in from the bottle when the car cooled off. Just for the heck of it I bought a new Delco cap (RC24) and now the radiator always stays full, lot of aggravation for 8.00 lol. The delco cap has some kind of valve on it the stant didnt and I assume the closed setup doesnt work right with it for some reason.
