Overheating? cold bottom hose head over 110 celcius

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missfixit70
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Re: Overheating? cold bottom hose head over 110 celcius

Post by missfixit70 » Thu May 26, 2011 7:44 pm

No disgrace in going for a cheaper option :wink: just make sure it's reading sumat sensible, giving half a story just makes it harder to give sensible answers to help.
When you ran it up again, did you let it get hot enough for the fans to kick in? Be a good idea to do that & see what temp it gets up to (should be @96) & then when the fans kick in, the temp should drop quite quickly back down to low/mid 80's.
If the stat hasn't been replaced in recent history, won't hurt to get a (proper) new one in, just don't go for a cheap copy.
Personally I'd move the temp sensor to the metal stub for the top hose on the drivers side, just below where the fitted gauge sensor is (mines fitted with a jubilee type clip, with some high temp silicon sheilding the sensor from any wind, not that there is much there), worth going for the mod that resensitizes the gauge too.
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Re: Overheating? cold bottom hose head over 110 celcius

Post by haydn callow » Thu May 26, 2011 7:51 pm

If you got a reading of 110C at the Bolt hole at the back of the cylinder head you were WELL HOT.......I doubt that was a true reading.......
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Paulinwales
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Re: Overheating? cold bottom hose head over 110 celcius

Post by Paulinwales » Thu May 26, 2011 8:13 pm

think it got to 108 before i pulled in and switched the engine off. not sure how accurate the probe is said +/- 1'c on packet but i only paid £10 for it?!

in normal driving goes to around 100 max so paniced and stopped (usally around 95 unbless pushed)

sound around right? I have no comparative data
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Re: Overheating? cold bottom hose head over 110 celcius

Post by stilldesperate » Thu May 26, 2011 9:36 pm

Paulinwales wrote:think it got to 108 before i pulled in and switched the engine off. not sure how accurate the probe is said +/- 1'c on packet but i only paid £10 for it?!

in normal driving goes to around 100 max so paniced and stopped (usally around 95 unbless pushed)

sound around right? I have no comparative data
You do, Paul, it's the numbers you are used to when you're driving ... didnt you say that it's around 95 normal, and 109 when up hills?

If, because of a combination of innacurate meter and location of the sensor, the meter is reading (say) 15 degrees too high, that would give 80 degrees normal, and 94 degrees when it gets very hot up hills.... not a bad range.

The crucial point is that there wasnt a "boil-up" when you took the pressure cap off .... I agree with Kirsty, probably no huge problem.

Good luck with your tests tomorrow, and keep us informed :D

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Re: Overheating? cold bottom hose head over 110 celcius

Post by Timnz » Fri May 27, 2011 4:49 am

depending on the ambient temperature, you can check the circulation of coolant just by driving for at least 15-20 minutes, then park and leave it idling. check the top and bottom hose temperature. Sometimes I can drive 10km even at 40-50 km before it is warm at the bottom hose.
If you drive at 100 km/h even for an hour, then stop and check the bottom hose, it may be cold, until it has been idling for a minute or two. Then the fans should kick in and the bottom hose will get hot.
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missfixit70
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Re: Overheating? cold bottom hose head over 110 celcius

Post by missfixit70 » Fri May 27, 2011 11:33 am

Timnz wrote:depending on the ambient temperature, you can check the circulation of coolant just by driving for at least 15-20 minutes, then park and leave it idling. check the top and bottom hose temperature. Sometimes I can drive 10km even at 40-50 km before it is warm at the bottom hose.
If you drive at 100 km/h even for an hour, then stop and check the bottom hose, it may be cold, until it has been idling for a minute or two. Then the fans should kick in and the bottom hose will get hot.
Not strictly correct. With airflow across the rad & coolant circulating, the bottom hose should be cool, so when you pull over after a run, initially the bottom hose will be cool, as the air has been rushing over the rad & the coolant whizzing round (water pump speed relative to engine speed). If the bongo is then left idling, the coolant will be flowing slower around the system & no airflow across the rad, so the system temp will rise, the bottom hose will get warm, then hot until the engine temp reaches 96c at which point the low speed fans should kick in, cooling the coolant going through the rad until engine temp gets down to @ mid 80s from memory (cools quicker if you rev the engine as the fans kick in as it increases the pump speed).
In simple terms, the bottom hose gets hot - then the fans kick in :wink:
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Re: Overheating? cold bottom hose head over 110 celcius

Post by Paulinwales » Sat May 28, 2011 5:15 pm

hi guys, drove it around yesterday and temp did not get past 95'C - seems like it was a temp probe battery low problem.

thanks for all the info has inproved my knowledge of the coolant system

rgds Paul
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