Where does your needle sit (seen this question lots of times
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- lloydy
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Re: Where does your needle sit (seen this question lots of times
this is the same part number as mine. it has a few engines types listed there, but the part number is pretty much the same across the vw range
https://www.vwheritage.com/shop/0441211 ... lf-t25-t4/" onclick="window.open(this.href);return false;
https://www.vwheritage.com/shop/0441211 ... lf-t25-t4/" onclick="window.open(this.href);return false;
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- kevtherev
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Re: Where does your needle sit (seen this question lots of times
I have argued this with Martin before.
I assumed that if you could maintain 87 deg the stat would open partially, if the temp increased a degree then the stat would open a degree more.
Wax melts at 62-65 deg so this is clearly not wax from a candle
To quote the wikipedia
I assumed that if you could maintain 87 deg the stat would open partially, if the temp increased a degree then the stat would open a degree more.
Wax melts at 62-65 deg so this is clearly not wax from a candle
To quote the wikipedia
I can only relate to this, however Martins experience says different.The thermostat stays closed until the coolant temperature reaches the nominal thermostat opening temperature. The thermostat then progressively opens as the coolant temperature increases to the optimum operating temperature, increasing the coolant flow to the radiator. Once the optimum operating temperature is reached, the thermostat progressively increases or decreases its opening in response to temperature changes
AGG 2.0L 8V. (Golf GTi MkIII)
- lloydy
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Re: Where does your needle sit (seen this question lots of times
i had a google on the tdi forums, and it does say start to open at 87, fully open at 102. I've never looked at the wbx ones, so can't really comment on that
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Re: Where does your needle sit (seen this question lots of times
WIKI's are written by people like us ...
If we agree on the basic function of how the stat works..that the changing of the wax from a solid to a liquid creates the expansion that forces the pin out and the valve open? yes
Are we suggesting that the wax goes from partially melted state to fully melted state over that wide temp range?
Or
Melts completely at 87C but then continues to exponentially expand at it heats further...this I could except..if it wasn't for the many practical observations I've done with my students.
And you guys have all felt the sudden and extreme heat change of a top hose when the stat opens....not a gradual heating but a rush of heat?
You have me doubting myself though....when I do this next time I will try and video it, either way, I'm happy to admit if I'm wrong.
Martin
If we agree on the basic function of how the stat works..that the changing of the wax from a solid to a liquid creates the expansion that forces the pin out and the valve open? yes
Are we suggesting that the wax goes from partially melted state to fully melted state over that wide temp range?
Or
Melts completely at 87C but then continues to exponentially expand at it heats further...this I could except..if it wasn't for the many practical observations I've done with my students.
And you guys have all felt the sudden and extreme heat change of a top hose when the stat opens....not a gradual heating but a rush of heat?
You have me doubting myself though....when I do this next time I will try and video it, either way, I'm happy to admit if I'm wrong.
Martin
1989 California 2.1MV
- kevtherev
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Re: Where does your needle sit (seen this question lots of times
To quote a supplier of automotive waxes..
Yes the wax melts but as I believed the expansion opens the valveEach thermostat contains a plug or pellet of wax, designed to melt at a particular temperature or over a specific temperature range. On melting, the volume expansion in the enclosed system works against and finally overcomes the spring loaded seal, effectively introducing coolant into the engine and regulating operating temperature. This rate of expansion can be regulated with the introduction of Alkanes, thus smoothing the range of movement
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Re: Where does your needle sit (seen this question lots of times
turn engine on red light flashes goes off as normal then starts again needle goes right over to max hot ,this all happens within 6 seconds.
changed sensor under engine ,changed sensor in expansion tank still same,i have a red sensor I think it is by thermo housing but no one seems to have one
its been on for 11years no trouble ,started as soon as it got cold problem that is,steve
changed sensor under engine ,changed sensor in expansion tank still same,i have a red sensor I think it is by thermo housing but no one seems to have one
its been on for 11years no trouble ,started as soon as it got cold problem that is,steve
- kevtherev
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Re: Where does your needle sit (seen this question lots of times
There are no coolant senders under the engine.
You don't state your engine type... For the correct temp sender.
If you look in the wiki, the coolant level sender and relay 43 is responsible for the light flashing.
The wiki explains how to check what's causing the flash, assuming you have a full to the brim header.
The coolant temp sender is responsible for the gauge.
You don't state your engine type... For the correct temp sender.
If you look in the wiki, the coolant level sender and relay 43 is responsible for the light flashing.
The wiki explains how to check what's causing the flash, assuming you have a full to the brim header.
The coolant temp sender is responsible for the gauge.
AGG 2.0L 8V. (Golf GTi MkIII)
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Re: Where does your needle sit (seen this question lots of times
eagle wrote:turn engine on red light flashes goes off as normal then starts again needle goes right over to max hot ,this all happens within 6 seconds.
changed sensor under engine ,changed sensor in expansion tank still same,i have a red sensor I think it is by thermo housing but no one seems to have one
its been on for 11years no trouble ,started as soon as it got cold problem that is,steve
The Temp sender on the Thermo housing which sends signal to your gauge should be the black/green sender.
https://www.brickwerks.co.uk/coolant-te ... green.html" onclick="window.open(this.href);return false;
1988 VW T25 Westfalia Club Joker, 2.1 iDJ
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Re: Where does your needle sit (seen this question lots of times
Sorry to fog this thread up but wondered if anyone can recommend how or where I use this infrared gun to test my Mk1 GTI temperatures and what they should be.
After 40mins idle I aimed it at the temp sender housing and it was reading 75.5c with the temp needle just to the right of the warning light.
After 40mins idle I aimed it at the temp sender housing and it was reading 75.5c with the temp needle just to the right of the warning light.
1983 Autosleeper Trooper - 1.8 Gti Conversion