Black01M6SS

iTrader: (3)

Just read and tell me the truth guys.

Do you think I hurt it?

We finished up installing my new 402 yesterday. Today we went over everything and decided it was time to fire it up. So we start it up and I'm sitting in the car watching my wideband like a hawk. "Rough tune" I was holding the RPMS around 2300. AFR was switching back and forth from 14:1 to 15:1 making my narrow band blinky light guage alternate like it should. After around 3 minutes the coolant temp hits 180. I honk the horn and have my friend put a shop fan in front of the car thinking that would keep it from going any higher. I have a 160* thermo. Five minutes in the timp had continued to climb up to an indicated 220* and that is where I shut the car off. Withen seconds of shutting the car off the guage shoots up and pegs out hot... WTF As soon as I shut it off my friend grabbed a spray bottle of water and started spraying down the radiator. We disabled the fuel pump and I jumped back in the car and spun it over a few times with the starter to get some coolant flow. Withen around 2 minutes the guage comes back down. The car is cooling as I type this. After I shut the car off I turned the key back on and didn't hear the cooling fan blowing

I'm about to go back out to the shop and figure out what is going on with the cooling fan. Let me know what you think guys good or bad. I feel sick.

white2001formula

iTrader: (5)

I would definitly get some issues worked out before a refire on the engine. Are you sure that the thermostat is opening properly?

To the issue with the temp skyrocketing, it "may" be O.K. When you turn off the engine, everything just stops. The water pump would no longer be pumping water through the system. As the cooler/warmer water begin to mix and reach an equilibrium it probably shot up high where the water temp sensor is located.

A few weeks ago I was driving my Formula, and I came back out of the post office from mailing a letter and my "dummy" temp gauge was way over 210. It took me just driving away, and getting back into regular traffic for the water to circulate and the water to get back down to operating temp.

The tune could definitly be off if you did some big changes w/the new motor. That would explain the lean condition. More combustion volume, same amount of fuel spraying from a previous tune.

-Chris

PBMFIsMe

iTrader: (5)

I doubt that you hurt it. It could have been a problem, but it sounds like you were paying attention and caught it before anything really bad happened.

TopFlite

Make sure that you have "burped" the coolant system properly and there are no air pockets left.

DrkPhx

iTrader: (15)

Good point. I idle the car with the radiator cap off until the engine coolant temp stabilizes.

danf1000

iTrader: (2)

There's nothing wrong with the engine. A pinging sound from overly hot combustion chambers pre-igniting the mixture can indicate serious heat. From there, a decreased clearance from the piston to the cyl can destroy rings/pistons.

veee8

iTrader: (40)

Yeah she's fine. Double check that t-stat, and make sure the fans are working right. My 6.0L hit 235 when the t-stat wouldn't open once. You caught early enough.

needadvice

Your engine is fine. I threw a serpentine belt once while doing a serious highway run up to about 160mph, looked down and my temp guage was pegged all the way to the right. I shut it down and rolled to a stop. Let it cool for about 10 minutes, started it up and got it off the highway, it pegged again and I turned it off as I rolled into a parking spot. Came back the next day with a new belt, drove away and it was fine and has been for the past 4 years since that happened.

T-stat did not open, coollant temp sensor if bad and reading wrong or you may have an air bubble in the system. If the coolant wasn't boiling over when it got hot there most likely is not a bubble in the system. Was the engine bay and engine block and heads actually hot when the temp went up that high, if not its probably a bad sensor. When my temp pegged to the right and I opened the hood I couldn't even touch the air lid, stb, fuse boxes, intake...nothing, it would have burned my skin badly.

Jimmy P

iTrader: (177)

I wouldn't loose any sleep over it.

RoDan

it'll be fine

fotoboy

iTrader: (1)

need to burp system, a engine will not heat up the way it did and gave your a false reading with no fire in the engine.

Black01M6SS

iTrader: (3)

Thanks for the reassurance guys. I'm pretty sure we had the air out of the system. We have a tool where I work that pulls a vaccum on the cooling system then you let it suck the coolant in. I think it is fine like you all said. I never figured out why the fans wouldn't come on. I reflashed the PCM to make the fans come on at a lower setting and they were working when I fired it back up. I spent the last few hours tunning on it and it never over heated again. I finally got it to idle and got the AFR decent at idle/part throttle. I put around 30 miles on it logging the AFR and it is anywhere from 12.9-15:1. My narrowband is switching while crusing so I think its safe as long as I don't get into the throttle to much. Tomorrow I'll start doing some AutoVE tunning.

Thanks for the replys everyone. I just kind of panicked when I saw the gauge peg out after I shut it off.

Hark_Z

iTrader: (12)

Let us know when you get some numbers from this setup.

01WS6/tamu

iTrader: (37)

Thats good to hear. Now you can enjoy it but after spending that much money it definitely does not take long to get paranoid. If it makes you feel any better I have seen more than a few LSX's in various vehicles come through our shop in the last ten years that got so hot they just flat quit and then came in our hook. AFTER cooling off and correcting the problem every one of them fired up ran and was fine. Two of them were oilfield trucks that are still in use five years later. The other one is my moms suburban after if broke a rear cooling line to the heater. That has been quite a while ago and it's 6.0 alive and well. There have been others but they have since been wrecked traded in etc.

7420NW7TH

iTrader: (8)

Ha ha, thats funny. I'm not laughing at you I'm laughing with you. Same thing happened to me after installing my 408. Pegged the engine temp gauge and steam came rolling out from under the hood while I was driving it. Turned out to be fan #2 fuse was blown. Check both your fan fuses.

By the way....my engine was fine and it sounds like it got alot hotter than yours did.

Caveman

iTrader: (2)

I did that before after changing heads, thought I had the motor/radiator full of coolant but there was still some air in the system. I drove the car around the block after letting it idle for a minute and the temp went over 220 quickly. I let it cool off and topped it off with water and it was fine.

RoDan

remember, the temp gauges are dummy gauges.... they will pop over to hot when they get above X temp. So it can throw you for a loop thinking you overheated it bad when in reality it was just maybe 10 degrees overheated.

aNuBiS

iTrader: (25)

sidewayz28

iTrader: (24)

x1000000 when i had an air bubble in my system my car was overheating like CRAZY...

03 BUSA

iTrader: (25)

I agree I do not think you hurt anything. Sounds like air pocket. Jack the front of the car in the air alittle to get the air out. Let the car idle with the cap off and keep adding until you can't put anymore in the radiator.