New 408 is overheating! Air Pocket?
New 408 is overheating! Air Pocket? Got the thing running long enough to warm it up. Temp steadily rose all the way to 225 and then I shut her down. I did have the cap open as I was filling with coolant as it went down. Is there any easy way to vent any air pockets?
I am assuming its an air pocket unless someone else has another idea?
THanks
I am assuming its an air pocket unless someone else has another idea?
THanks
was the coolant all the way up to the top of the cap?
What i have done was simply let her run with teh cap off until the temp sensor opens up. SHE"LL guzzel a **** load of coolant, which is normal when she opens up. Just keep filling her up until she is done. (WOW!!!) Give it some gas, and wait unitl it has leveled off for a few minutes.
You can disconnect the coolant line that goes to the driver side of the block, a small hose. IF you did the tb coolant by-pass, its that one. OR its the hose going from your block (driver side) to the tb. Disconnect it from the tb and run the motor. This, relatively speaking, is the highest point and where you can use to get all the air out of the system.
I dont mess with that anymore, just fill her up and run it, give it some gas, fill her up again, run it some more.... repeat if necesary until she levels off.... PRESTO!!!
But keep in mind if you are using the stock temp sensor, she WILL, and i repeat WILL get and STAY HOT!!!!! I replaced the temp sensor with a 160* sensors and temps ARE WAY BETTER!!! only gets above 200* if in hot, mid day traffic and that goes to 215-219... while idling in front of my house, giving it hell, with and without A/C, never went over 192*.
good luck, she'll run hot remember, so dont panic that much...anything over 225 or at 225 you should be worried a little.... i have seen my temps as high as 235 in traffic and that was scary!!!
What i have done was simply let her run with teh cap off until the temp sensor opens up. SHE"LL guzzel a **** load of coolant, which is normal when she opens up. Just keep filling her up until she is done. (WOW!!!) Give it some gas, and wait unitl it has leveled off for a few minutes.
You can disconnect the coolant line that goes to the driver side of the block, a small hose. IF you did the tb coolant by-pass, its that one. OR its the hose going from your block (driver side) to the tb. Disconnect it from the tb and run the motor. This, relatively speaking, is the highest point and where you can use to get all the air out of the system.
I dont mess with that anymore, just fill her up and run it, give it some gas, fill her up again, run it some more.... repeat if necesary until she levels off.... PRESTO!!!
But keep in mind if you are using the stock temp sensor, she WILL, and i repeat WILL get and STAY HOT!!!!! I replaced the temp sensor with a 160* sensors and temps ARE WAY BETTER!!! only gets above 200* if in hot, mid day traffic and that goes to 215-219... while idling in front of my house, giving it hell, with and without A/C, never went over 192*.
good luck, she'll run hot remember, so dont panic that much...anything over 225 or at 225 you should be worried a little.... i have seen my temps as high as 235 in traffic and that was scary!!!
160 stat already installed. Worked fine last year. I did fill the radiator up to cap and then started it up with the cap off and kept filling as it guzzled. Temp just keeps going up though. Guess I will just have to keep trying.
Still overheating! I didnt unhook the TB bypass because it looks to be the same as leaving the radiator cap open. Temp just goes straight up to 22X even with the fans. I assume its some sort of air pocket because when I do tighten the cap and it heats up to 220, I can open the cap and steam just rolls out of the hose that goes to the TB but there is no pressure.
Mine did that a few times when i put the cam in it. I kept putting in more and more water untill it stopped. I got it running the day before i was to drive it 1.5 hours on the stock tune to houston for a tune, so needless to say i was a little freaked out lol. I grabbed 3 extra gallons of water, 2 quarts of oil, and hit the road 
I'd say keep trying it. Coolant systems can be fishy sometimes, and all you really need is some patience.
I'd say keep trying it. Coolant systems can be fishy sometimes, and all you really need is some patience.
Teching In
Joined: Jan 2006
Posts: 13
Likes: 0
From: Dallas
You need 2 take a 10mm socket and loosen the coolent line at the top of the block.Its the one that the tb by pass goes 2 I usually use the one on the drivers side.Just take it loose and let the car run you will get alot of air out of the block that way.Its a little messy but its the easiest way
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I think I got it figured out. I guess you really need to rev it to get the crap moving. I reved her to about 3k a couple times and woosh bye bye goes the coolant. 
Just idleing it was not taking anything. Its weird. One more issue in the books, last thing is to stop the banging on the floor boards and shes ready for the street!
I just put in prothane motor/tranny mounts and now its a pretty steady bang at idle. Couple hours under there tomorrow and I should be good.
Just idleing it was not taking anything. Its weird. One more issue in the books, last thing is to stop the banging on the floor boards and shes ready for the street!
I just put in prothane motor/tranny mounts and now its a pretty steady bang at idle. Couple hours under there tomorrow and I should be good.
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