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My main coolant tank in engine bay seems like it has enough coolant but my light is still on? Perhaps the float device attached to the cap is sticky and not working properly? Has anyone had experience with this? I pulled it out and tried shaking it hard. Could hear the slider inside (looks like some type of a float) break free. I put it back in, light went off. A few weeks later same thing. Is there a process other than replacement that helps here? Thanks.


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Wingless Wonder
1988 Esprit Turbo
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A common problem. Try and clean the sliding mechanism with a toothbrush or something so that it slides freely.


Also, inspect the plastic coolant reservoir for cracking. Most likely area is to the right and an inch lower than the filler cap.
 

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A word of caution, be very careful removing the coolant level sensor. If the slide assembly comes free from the tube, you will have to buy a new one and they are NOT cheap. Ask me how I know this. ;)
 

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Wingless Wonder
1988 Esprit Turbo
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How do you know this? :D

You SAID to ask. :grin2:




Got any pictures of the old assembly? This would help others repair the sensors. :rolleyes:
 
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Well, I applied a little more pressure than necessary attempting to removing said sensor and it rapidly separated from the tube inside the tank covered in that brown goo. I believe I paid $120 from JAE for the new sensor.
 

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You do not need to remove the sensor. Remove the whole tank and wash it out with HOT water to remove the brown goo. There is no sliding thingy. It is a lever off the end that is supposed to lift up and float when the level is high enough. That tank is always supposed to be kept full. The overflow tank level is supposed to fluctuate (that's the one in the R/H wheel well). Take the hose off that connects the header tank with the overflow bottle and make sure it is not plugged up. You can also wash the overflow tank to make it easier to see how much is in there. Refill both with 50/50 soft water and anti-freeze. The overflow tank is only filled to the cold line (when cold of course!). The way I fill it is to remove the hose under the rad cap and using a funnel, pour in the anti-freeze till you get to the cold line.
David Teitelbaum
 

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Here is a photo of the sensor and float from an original part. The float gets gummed up and sticks. Very difficult to clean without removing the cap. The cap fell off when I removed the sensor the first time. Bought a replacement. I tried super glue on the plastic but it failed. I will probably try that ultra violet "welding" glue next.

Be very careful removing the sensor. It can be a VERY tight fit.
 

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Cleaned mine up the way David describes. Couldn't get the sensor out, but in my case it cleaned up OK in the laundry tub.

If you pinch off the lower hose at the bottom of the tank it can all be done without draining the cooling system or introducing air. Mine had severe plugging on the hose that runs to the elbows at the front of the engine. The steel sleeves in the plastic nipples corrode and can block the nipple off. Also note the pressure cap on the bottle should have a rubber gasket on the sealing face.

HTH

Stu
 

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Wingless Wonder
1988 Esprit Turbo
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So, HOT water is all it takes to dissolve the goo? Would a penetrant/cleaner (PB Blaster, WD40, or CLR) or speed up the process?

Unfortunately the reservoirs are cracking and failing as well, so the sensors DO need to be replaced or moved to the new ones (which are available from JAE).
 

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The V-8 ones aren't all that bad yet (they aren't as old) but eventually they will fail. Unfortunately removing the sensor will probably damage it and necessitate replacement also. You have to be really careful what solvent you use, the wrong one will dissolve the tank! Hot water and a long bottle brush (and some elbow grease and patience) is all you really need.
David Teitelbaum
 

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I'm not sure what "lever" David is referring to (maybe an earlier Esprit?), but all the V8s have the Peugeot tank and sensor with the sliding float. There are two parts to the unit:

1) is the "inside" electrical portion which is merely two wires and a reed switch.

2) is the "outside" portion where the float resides, and where coolant is allowed to enter via small holes. This is the part that gets gummed up.


The switch illuminates the dash light when the float (which also contains a magnet) gets to the bottom of its travel in the switch. At that time, the magnet pulls the reed switch closed and turns on the light.

The failures for the switch are either that the float gets dirty and seizes in one position, or that the reed switch inside fails. In either case, they can be fixed for with about a hour and $2. Don't ever throw one away!

I'll try to write a tech post about how to fix these. I took some photos the last time I did it.

Jake
98 V8 #5651
 

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On my '99 the float switch is a lever arm that floats, no sliding thingy, just an arm that floats when the coolant is above the lever float. On mine it was so gummed up that it wouldn't move and was stuck so that if the level went down the light would not have come on. Hot water washed it up. What makes it worse is when the level is not all the way up to the top. The gum floats on the surface and when it cools it gums everything up. Keep the header tank full and let the overflow bottle fluctuate. My DPO didn't do that (maybe he didn't know about the overflow tank?) and kept the header tank 1/2 full. The hose going to the overflow tank was also all plugged up and the overflow bottle was all gummed up and dry. Once I cleaned everything up it all functioned properly.
David Teitelbaum
 

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How does this work on a 1987 HCi G-car? My coolant level in my tank is always full, but quite often the coolant level warning light will come on. Sometimes it is on briefly, sometimes it will stay on for hours.
 

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Wingless Wonder
1988 Esprit Turbo
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How does this work on a 1987 HCi G-car? My coolant level in my tank is always full, but quite often the coolant level warning light will come on. Sometimes it is on briefly, sometimes it will stay on for hours.
The only time that happened on my car, there was a loose connection on the OUTSIDE of the header tank. The sensor terminal is on the lower RH side of the tank (easiest to access it from underneath).

There is no float to gum up, on Esprits with the metal tanks.
 

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The only time that happened on my car, there was a loose connection on the OUTSIDE of the header tank. The sensor terminal is on the lower RH side of the tank (easiest to access it from underneath).

There is no float to gum up, on Esprits with the metal tanks.
Thank you Atwell. I've had a lot of problems with crappy electrical connections on my car, so I have been slowly replacing them. When mine comes out of hibernation, I will take care of this one as well.
 
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