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Discussion Starter #1
I'm replacing the coolant on my 2001 Esprit, and I'm a little scared of the last step where you open the radiator bleeder while the coolant is scalding hot. Won't all the coolant spray in my face at that point? Why does it have to be bled with hot coolant? Can't I run the car, let it cool, and then do the final bleed at that point? I'm hoping the Lotus lawyer was on vacation that day and the tech writers decided to amuse themselves.

I have removed the radiator drain and bleeder, which I guess is a rarity, so I'm lucky there. Although I did notice some milky stuff when I ran some distilled water through the pipes to flush them. Is there any way that can be from something that won't eat my wallet? I don't know when the coolant has last been replaced, although I don't think that will cause any milky residue. I was planning to replace the coolant, drive it for a month, and then drain and check the fluid again to see if I'm in trouble. Is that a bad idea?

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I have never used the radiator bleed screw, and always follow this method:-

Park the car nose down on a hill / slope so that the rear end is about a foot higher than the front. ( You might want to put a brick/chock under a wheel in case your parking brake doesn't hold. Remove the cooolant header tank lid and start the car. The coolant has to be hot so that the thermostat opens, and also make sure the heater is set to the hot position. That will ensure that all coolant passageways are open. As the coolant is pumped around the system, any trapped air should bubble up to the header tank and escape.

When finished replace the header tank lid. Job done.
 

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Wingless Wonder
1988 Esprit Turbo
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Don't be afraid (tho' the Service Notes warn of scalding).


What you do is, loosen the header tank cap on a cold engine. Have the front wheels turned left.

Start the engine, and feel the bottom radiator hose near that LF wheel. Soon as it starts to get warm (meaning the thermostat is open), loosen the bleed screw (also accessible through the front wheel opening). When the coolant comes out in a stream (meaning, no air) you are done.

As mentioned, have the heat control on HIGH so as to purge any air out of the heater matrix.

The coolant will NOT be that warm when it first starts to flow, so oven mitts are NOT necessary.

Tighten the header tank cap. Top up the overflow bottle in the right rear wheel arch.


Just check the overflow (cold) the first few drives and top up as necessary.




You can also drive leftover air out of the cooling system by revving the engine while you drive :coolnana: especially on right hand curves (entrance ramps are PERFECT for cooling system purging). rotfl
 

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Discussion Starter #4
That does sound easier, especially since when I remove the upper bleeder (by the engine) and fill up the header tank, no coolant comes out the bleeder. I can get the rear up on ramps and try your method.

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Discussion Starter #5
I must have just missed your post with my post Atwell. Running the engine until the thermostat opens makes sense. The manual says to run the engine until the fans come one twice, and then open the bleeder, which seems unnecessary.

Also, does it matter what the level is in the overflow tank? I thought I just fill up the header tank once everything is bled, and then whatever makes it over the overflow tank is fine. As long the header tank's level ultimately is above the tank's joint, isn't that all that matters? I'm just curious.

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Wingless Wonder
1988 Esprit Turbo
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Also, does it matter what the level is in the overflow tank? I thought I just fill up the header tank once everything is bled, and then whatever makes it over the overflow tank is fine. As long the header tank's level ultimately is above the tank's joint, isn't that all that matters? I'm just curious.

Thanks
Just keep the header tank (in the engine bay) as full as you can.

As the engine warms, the coolant level will expand... so don't begin with a cold engine where the header is filled to the brim. It will overflow a little if you do.

The normal level of coolant in the Wheel Well Reservoir should be at the "joint" (beltline, half-way up) to start. On my 4 cyl, anything more than that will expand out of the tank after the engine warms fully.

++++++++

One watchpoint when looking at the plastic tank in the wheel-well: Over time, the coolant will leave a stain, which may lead you to think there is fluid in it when there isn't. So remove the tank and clean it out (those coffee pot scrubbers work well for that task).
 
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