99 V8 Coolant/Water level sensor testing/service rebuilding?

[cliffq]

I am trying to test if my coolant level sensor in the header tank to see if it is working correctly. Does anybody know what the correct resistance levels in ohms are for this sensor for the full/empty marks?

Mine was slowly discharging some gooey material out of the two pin holes into my header tank. I may have made a mistake, but I opened it up to see if I could clean that out. Now I realize that the grey goo is some water sealant that is supposed to be there. Anybody know what that is exactly? Has anybody attempted to service or rebuild one of these sensors?

Many thanks,

CQ

[Kylie]

All I know is that it is really important to get them cleaned frequently acordding to a good source. If and when you find out how do it can you post up some pics and procedure? I will be cleaning mine when it comes home.

[cliffq]

Thanks, Kylie. Will do. Initially, what I have been told is that you can simply run water into the holes for an extended period to clean it out. My issue is more on the rebuild option.

[snuffy]

I had that type of problem on my Spor 350 and GT3. The float gets gunged up, sticks and does not float so you get a low coolant light. I assume you took the end off the plastic tube and removed the float ? Just clean all the gunk out, pop the float back in and glue the end cap on with something like appoxy resin glue so the heat wont unstick it. The worst that can happen is the end cap comes off and goes into the tank, in which case you can remove the tank and fish it out and glue it back on again.

[cliffq]

Thanks snuffy. My 99 V8 doesn't use a float but appears to work as a variable resistor or an on/off switch....no moving parts, just wire leads. I think most Turbo V8's must have it.

BTW Love your Noble M12 GTO...I don't think we can get those in the States.

[snuffy]

Hi Cliff

Are you sure ? In the header hand there is a long ( 3 to 4 inches or so ) stiff plastic tube that screws into the tank and has two wires coming from it. That tube has a centeral spindle ( for want of a better word ). On that spindle a little float, about 3/4 inch long slides. When it slides up to teh top it makes the circuit and so the low coolant light is turned off. So when the water level drops, the float drops, breaks the circuit and the light comes on. If you unscrew the tube and shake it you will hear the float move about and it should operate the light.

Having said all that the US cars my be different to the UK cars.

And the Noble is avaialble in the US, there are about 300 owners, not many, but then there are only about 700 in the UK.

Snuffy

[cliffq]

Snuffy,

Yes, mine is different. Mine is a black cylinder about 5 inches long has two external male prongs for the wire harness to connect to....so similar to your description for the outside. But when you open the cylinder you find the two wire leads of different lengths and some sort of sticky, gray sealant...no float or moving parts... One of the leads is deeper than the other, so it appears that if the water level drops below the higher lead, this cuts the circuit to tell the ECM that your level is too low...but I am not sure exactly if this is how it works.

[Kylie]

Cliff perhaps post up some piccies to see