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Old 22nd February 2010, 16:34   #161
Simon W
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I've got a Kaiser housing and the car does take a lot longer to warm up than it did with the original factory-fitted thermostat. I think there may be a difference in spec between Kaiser's stat and the original MGR one.

With the new stat, it takes about 3 miles* more driving to reach normal running temp (according to horizontal bar on the dashboard gauge) hence the heater takes longer to warm the cabin up. Mind you, these heaters aren't exactly quick anyway.



Edit: *

Original stat: normal running temp reached in 1.0 to 1.5 miles.
Kaiser stat - normal running temp reached in 4.5 to 5.0 miles.

Last edited by Simon W; 22nd February 2010 at 16:38..
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Old 22nd February 2010, 16:55   #162
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stat was in housing, [it was fitted by Lates]
when stuck in traffic - heater blows hot air so assume engine is getting hot.
temp seems to raise to 50c quick enough, which makes me think the stat is ok
even left car running till fans kicked in everything appears fine then taken for drive, same results has in prvious post.
[had a car with stat removed could never get it above warm]
have to agree about engine being cold.
thermostat housing doing to good a job ? perhaps ??
drove home yesterday from rugby to merthyr 138 miles
only time engine got hot was in heavy traffic.
like i said, a bit concerned about engine not reaching normal temp.
not sure where to go from here ?
replace thermostat housing another £££ or get shot of car.
been a bit of a money pit lately.
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Old 22nd February 2010, 19:04   #163
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I think you are forgetting the weather. When you use the heater a lot in these temperatures, the cooling effect of the heater alone can be enough to cool the engine.
This is normal with heavy use of a heater, where there is an unregulated cooling of any engine, as the heater takes hot water from the engine, bypassing the thermostat, this is not a function of the metal thermostat.
The thermostat I use, starts to open at 80 degrees, and progressivley opens more as the temperature rises.
If you use the defroster for the front screen, the engine fan will also be running all the time increasing cooling on the radiator.

The thermostats are tested before installation, and I have yet to come across one that does not open at 80 degrees spot on! So unless there has been some physical damage to the unit, I doubt it will be faulty.

In order to verify this yourself, switch the heater off, and you should see the engine temperature rise.

Getting a feel for the thermostat operation can also be obtained by letting the engine idle and feeling with a hand on the outlet pipe from the thermostat housing. The pipe should become warm as the thermostat opens.

There would certainly be a thermostat in the housing, you would find it hard to miss that one! I am sure also that Lates would have noticed if it had gone AWOL. I don't think you have to worry about that.

Thus, heater off, defroster off. Let us know what you get.
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Old 22nd February 2010, 19:15   #164
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58-66 C seems too cool to me and the Dash gauge will only be reading a 1/4 to 1/3 am I right?

Simon what is your Temp reaching on tootling about sort of drive and then cruising in Top Gear?

Can you report some readings back with Heater on & off too?

CDT/i's seem to get up to temp in the Winter with the heater on or not!
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Old 22nd February 2010, 19:58   #165
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Does anyone remember the old leatherette radiator muffs of the 50s and 60s. We had very cold winters then, (like now 2010 !) and cars would not warm up properly on short journeys. There is a lot in what Kaiser says, the heater is actually cooling the engine just like the radiator with ambient air at 0 or below coming in rather than the 7-8c of our "normal" winters.

At one time there were Summer and Winter thermostats as well. I have noticed with my MG Rover plastic thermostat housing the heater still is taking some time to heat up in this cold weather.

Kaiser - I still have you ally housing in the garage, as the plastic one is still good with no hint of a leak. If I sell the car before I fit it, your housing will be supplied to the new owner !
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Old 22nd February 2010, 20:16   #166
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i have been running the car with heater and defroster off has it's baltic with them on.
pipe gets warm.
i'm well pleased with the metal housing [been overly worried about overheating]
like i said, it seems to be working o.k.
just reporting feedback has was asked for in this post.
sorry if it offends anyone has that was not my intension.
just saying it has i have found it. honestly.
more than welcome to have a look.
i'm sure i'll eventually get to the case of the problem.
kind regards Colin
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Old 22nd February 2010, 20:22   #167
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Absolutely nobody is offended !! Thats what this forum is for; to share experiences so all can learn from others triumphs and failures.
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Old 22nd February 2010, 20:26   #168
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I have just remembered something about Kaiser's original fitting instructions about space to allow coolant to bypass the radiator and pass back into the engine. It's in a post somewhere. I believe the MG Rover unit still allows some bypassing of coolant. If this is so, it would explain cooler running as with no bypass all the coolant will pass through the rad. In this cold winter, it could have more effect than would normally be spotted or noticed.
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Old 22nd February 2010, 20:59   #169
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Fraser, you are right. There is a small bypass built into the unit, to prevent air-locks and thermal shocks.
This bypass will allow 2% of the of the full flow through, so it will have very little effect on the heater.
The main aim with the design is to ensure maximum cooling of the engine at high ambient temperatures, and to that effect, there is a modification which allows full flow to the radiator 30% earlier than the standard thermostat. That, however will only take effect with a thermostat 70% open and thus, unless the unit is faulty, this will have no influence at these temperatures.

It is possible that your temperature sender is faulty, and indeed, 58 degrees sounds low. If the sensor (rightly or wrongly, as the case may be) reads 50 or 60 degrees, it believes the engine still needs a rich mixture (choke). That could explain increased consumption. I would try and investigate the accuracy of the sensor. That can be done be substitution or external temperature measurement. Rule of thumb is that you can, just, keep your hand on something that is 60 degrees. So if you can rest your hand on the engine block, it runs too cold.

To make sure your heater is indeed off, switch to ECON and lower the temperature on the display, don't use the fan. Make sure your demist button is not switched on. Start the car and let it idle. Put a hand on the outlet hose and see if you can feel a sudden rush of hot water in the pipe as the engine heats up, this should coincide with a temperature of about 80 degrees on your display.
I have on very few occasions seen my built in temperature gauge below halfway. On all occasions it was downhill, coasting at high speed in very cold weather. Only once, has the gauge in my V6 fallen below the normal while actually travelleing on a flat road, and that was last winter at minus 9.5 degrees at 140km/h early morning, full heater. As far as I recall my other gauge red about 70 degrees then.
My wifes gauge in her 1.8T does often drop during the coldest period in winter when the heater is on. Switching the heater off gets the gauge up quickly.
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Old 22nd February 2010, 21:07   #170
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remember looking at thermostat housing before it was fitted and had the impression that there was a nice gap between stat & housing.
thought it was a excellent idea.
weather has been cold hence the moan about lack of heat.
bit of a nuisance keeping the screen clear.
roll on summer hey.
it was 7c outside temp on the run home from rugby. thought the car would have got warmer.
now them muffs sound a good idea at the moment. where can i get them ?
my poor sheepskin coat is getting a hammering.
thanks for the idea & please keep them coming.
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