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Discussion Starter #1
Hello everyone with the weather changing and the Esprit spending more time inside I've decided to change the radiator fluid and put in a new thermostat. I just ordered a new one from JAE so it should be here in a few days. The question I have is I see where the thermostat housing is near the fire wall in the Y joint for the the return fluid and see what appears to be 3 bolts holding it on. The 2 on the side seem easy to get to but the 3rd is slightly under the top cover and looks difficult to get to. Can you do it with out taking off the top of the engine? Any help here would be greatly appreciated. If anyone has pics or where I can find them that would be a great help as well. As always thanks in advance.
Paul
 

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It's possible. If I remember correctly, I think that a 1/4-drive socket, with a swivel and a 6-inch extension will do it. But keep in mind that you can get all the room you need just by removing the 10 intake bolts, loosen two of the hose clamps for the turbo piping to the intake, and that gives you enough room to lift it an inch or two without disconnecting anything else. I don't recommend pulling it way up because it will strain the EGR pipe, but it should give you what you need.

For what it's worth, I'd also recommend that you start it by hand to make sure you don't cross-thread it going back on. It's really easy to mess it up with a swivel.
 

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Discussion Starter #3
Thanks for the info Add Lightness. I did just what you said and I was able to remove that last bolt without having to remove the intake bolts. I got in the engine bay and laid on the the engine so I could get a close up view of the bolts. I kept bumping my head on the the rear lid so I took off the gas struts and raised the lid far enough so I could get good access. I used a 1/4 inch drive like you said and a 13mm low rise socket with a swivel and walla. Now that I have it all out and the cleaning can begin around that entire area waiting for the new thermostat to arrive I opened the radiator drain bolt on the lower right hand side of the radiator. Once the new thermostat is in I'll flush what's left in the system then add new antifreeze 50/50n solution to the system. I have one question that bothers me. Once the fluid goes into the car and I start it up I know I have to turn on the heater on high so it can get into the heart core and open the bleed screw on the tube in the back of the engine near the thermostat until fluid comes out of it but in the manual it mentions another bleed bolt up front of near the left front wheel arch for the radiator bleed but I can't seem to find that one. Is that for the 4 cycles or is it for the V8's as well? Seems odd I can't find it if it' on V8 as well. Once this is all done I'll post pics of this process. Any help here would be appreciated. Thanks
 

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The radiator air bleed should be a square drive pipe plug on the top of the radiator and should be visible with a flashlight when viewing above the left front wheel.

When installing the new thermostat be certain to assure the new O-rings are properly seated in their grooves. They can be a bugger to keep in place so I use a couple of dabs of petroleum jelly (Vaseline) to hold them in place as I replace the housing. Then check how it sits using a flashlight and mirror. Those rings are easy to pinch.

Follow the directions in the manual precisely for refilling.
 

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Discussion Starter #5
Thanks Daily Driver. That helps a lot I'll go out in the morning and find that square bleed bolt I was looking at the bottom of the radiator. I was just wondering how I was going to get those O rings to stay in place when I put the housing back on I will do just that. Just out of curiosity has anyone used a vacuum filler to do drain and put fluid back into the system eliminating the use of having to use the bleed screws?
 

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Yup. I use the vacuum process. My compressor doesn't have the volume capacity to really get the pressure down as far as necessary but I have figured out how to work around that with multiple cycles of filling. You should still follow the air bleeding procedure in the manual to be certain you do indeed have the system filled. It doesn't take much air to make a mess from the overflow on heat-up. The first couple of drives after refilling you may notice the coolant level in the overflow tank will get a bit high when hot and go low upon cooling. Once all the air works its way out you shouldn't see more than about 1/2 to 1 inch of difference in the cooling tank between hot and cold states.
 

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Discussion Starter #7
That's great to hear Daily Driver. I think I will try that and order one from Amazon tomorrow. I have a 15 Gal 5.0 SCFM compressor hopefully that will give me enough volume the get the pressure down. Do you use it to also get out any remaining fluid in the system out as well? I think that would be great knowing you get all the fluid out of the system before you fill it up. I will use then bleed screws as well then just to make sure I get all the air out. This seems like such an easier way to do this.
 

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Here's a snapshot of the radiator bleed port accessible in the LF wheel well. I picked up these 1/8" BSPT fittings on Amazon and used them with some clear tubing to help reduce the coolant spillage. Also used on the radiator drain. Have to keep an eye on that clear tubing when bleeding since it doesn't like the heat so much, gets very soft. There's probably better tubing to use but I had this laying around.

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Discussion Starter #9
Wow, that's a great idea and pics to go with it. The mess I created just draining it was awful this is a much better solution. Thanks.
 

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From the first picture (the one of the top, left side of the radiator) you can easily see the bleed plug because the foam has been cut short. On your car the foam may be longer, covering that bleeder. Those extension hoses are nice but you really don't need them, you can loosen the bleeders and when the air stops and you start getting fluid you tighten them up. You don't have to get 100% of the air out, what little is let will work it's way out after several heat-cool cycles. Just watch the coolant level each time you stop for a while and add to keep the level up. Use a coolant pressure tester to pressurize the system when you bleed it, cold.
David Teitelbaum
 

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Discussion Starter #11
Thanks David. I was able to find that radiator bleed screw it was under that foam no wonder I couldn't find, which begs the questions has it ever been used before on my car. I'm the second owner and don't think the first owner really did much in preventive maintenance. I've done a lot in the last 3 years and it's always something but I love this car. Last night I ordered a radiator pressure tester and vacuum cooling system kit which should help me out. Thanks for all this info it really helps.
 

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I don't know what kit you ordered for the vacuum fill but you will probably have difficulty with any caps you get sealing on the stock header tank. Assuming you have the stock header tank, as I have, I suggest using the rubber cone-shaped universal attachment that commonly comes in most kits. I tried several kits and none of them had a cap to fit the header tank. If you use the cone-shaped attachment you must first check in the neck of the header tank for the red plastic insert. If present just pull it out before trying to get the cone to properly seal and drop back in when done. I have found using the vacuum approach results, as David said, very little mess from the air bleeding but the hoses as discussed above would be highly desirable for the gravity fill method as in the manual.
 

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When I use the vacuum filler I have to clamp off the overflow hose to the overflow tank in the fender. To use a vacuum filler you need a big enough air compressor so you can get a deep enough vacuum so you can pull all of the coolant in before you lose vacuum. While the vacuum filler saves a lot of time bleeding air out, the "old" way of using a pressure tester and opening the bleeder screws does work. Even with the vacuum filler, it takes a couple of cycles to get all of the air out.
David Teitelbaum
 

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Just FYI here are links to pics of a late model V8 in the factory assembly process. Note the radiator upper foam seal on the driver (LH) side does not extend to the end of the frame and does not cover the bleed plug, which is exposed. Maybe earlier models have a longer foam piece, and the change to a shorter foam piece was incorporated to encourage mechanics to use the bleed fitting 😆.


 
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