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What to do about coolant on initial startup 408?

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Old Mar 14, 2006 | 06:07 PM
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Default What to do about coolant on initial startup 408?

So when I did my cam change before I just left the radiator cap off and filled the radiator as the engine pulled it into the block by way of thermostat.

Now, for a new block/heads that have NO coolant in them, is it ok to just do the same thing? Fill up the radiator , start it up dry, and let it pull the coolant into the block as it needs it by way of temp of thermostat.

Or do I need to somehow prime/fill the engine block with coolant?

Thanks

ALMOST READY TO START
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Old Mar 14, 2006 | 06:24 PM
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I wondered the same thing with my engine I ended up starting it dry, and filled up the radiator as the coolant went down. I didnt have any problems with it, and havent after about 1500 miles *knock on wood*
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Old Mar 15, 2006 | 02:57 AM
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Hi on my 408 just add coolant to the tank, i managed to get a gallon and a half in let it sit a few minutes and keep adding untill it want go down anymore then when you start up just keep an eye on the level and add as required.
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Old Mar 15, 2006 | 04:50 AM
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I guess it just seems like we are putting a lot of trust in the thermostat to do its job. Temp will rise really fast with no liquid in the heads and if the thermo doesnt work right, one would think that the heads would warp really fast!
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Old Mar 15, 2006 | 07:17 AM
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If you want, fill up the coolant as much as you can and pull the hose from the vent line that enters into the throttle body and stick it (or better yet a longer hose) into a coolant jug. Then start the engine and as the water pump pressurizes the engine, the air will be purged out and the coolant will get into the heads. Once the engine has run for a few minutes, connect the hose in a normal way to the throttle body and add coolant again. Most of the air will be purged and the coolant will open the thermostat a little quicker on the next start.

Even if you don't do anything special on the first start-up, once you've topped off the coolant several times as GEN III advises and all should be well.

Steve
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Old Mar 15, 2006 | 07:37 AM
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Originally Posted by Steve Bryant
If you want, fill up the coolant as much as you can and pull the hose from the vent line that enters into the throttle body and stick it (or better yet a longer hose) into a coolant jug. Then start the engine and as the water pump pressurizes the engine, the air will be purged out and the coolant will get into the heads. Once the engine has run for a few minutes, connect the hose in a normal way to the throttle body and add coolant again. Most of the air will be purged and the coolant will open the thermostat a little quicker on the next start.

Even if you don't do anything special on the first start-up, once you've topped off the coolant several times as GEN III advises and all should be well.

Steve
U mean the vent hose on the top passenger side of the throttle body that has a short hose to the passenger side valve cover?

Thanks!
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Old Mar 15, 2006 | 07:53 AM
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We are required to use an SPX coolant refiller on all our cars at work when we drain the coolant. you shove the tool in where the cap goes. Hook it to an air hose and it pulls a vacuum on the cooling system. Then take the fill hose from the tool and put it in a bucket of coolant. The tool fills the system to the proper level without any air pockets.

Like this one
http://www.shop.com/op/aprod-p22261939

Last edited by 1BADAIR; Mar 15, 2006 at 08:02 AM.
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Old Mar 15, 2006 | 08:00 AM
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Another way is remove the thermostat. Start it and let it run for about 15 seconds.
That will fill all passages immediately.
Put the thermo back on and follow regular procedure.
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Old Mar 15, 2006 | 08:45 AM
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Originally Posted by PREDATOR-Z
Another way is remove the thermostat. Start it and let it run for about 15 seconds.
That will fill all passages immediately.
Put the thermo back on and follow regular procedure.
Nice... probably will be doing that! Would it be alright to just keep the thermo out for the first idle running cycle(~30 minutes)?
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Old Mar 15, 2006 | 08:51 AM
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Originally Posted by 99whitews6
Nice... probably will be doing that! Would it be alright to just keep the thermo out for the first idle running cycle(~30 minutes)?
Yeah, but I would just put it back on. The motor will be having enough problems as it is to find idle and the PCM will be doing all kinda learning. It is better that it reads as close to normal feedback from the sensors.
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Old Mar 15, 2006 | 09:34 AM
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Originally Posted by PREDATOR-Z
Yeah, but I would just put it back on. The motor will be having enough problems as it is to find idle and the PCM will be doing all kinda learning. It is better that it reads as close to normal feedback from the sensors.
I know its kind of ****, but I guess If I get the car to start first time I dont want to shut it off after 15 seconds. Guess I will just leave it dry!

What about removing the stat and just pouring coolant into the pump until it wont hold anymore, and then put the stat back in and call it good? Maybe it will work its way into the block and it wont be completely dry!
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Old Mar 15, 2006 | 09:54 AM
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Look all of this is not necessary unless you do not trust that the Thermo will function properly.
Running dry will not harm anything. Just keep your eye on the temp. In any case i would run a 160 in there.
You can tell if your thermo is working because the hose will be hard to squish when closed, once it opens it is much easier.
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Old Mar 15, 2006 | 10:36 AM
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I thought the water pump sucked the coolant into the engine?
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