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160 heater running cool

5K views 24 replies 9 participants last post by  Bagley 
#1 ·
Hi just joined the forum it looks really motivational and informative. I’ve just changed the gearbox on my 53 plate 160 tf without draining the cooling system but I’ve noticed the car doesn’t get up to normal temperature in cold weather and the heater is running only lukewarm. It’s been like that since I’ve bought so any ideas how to attack this issue would be much appreciated.

james
 
#2 ·
Yep, this forum has always served to be helpful to me. :)
In most F/TFs the needle stays a little below 'normal mark. The gauges are notoriously accurate / oil temp probably tells more...
Imo it sounds like you'd benefit from the usual 3-point bleed process focusing on the front two points in particular. I presume you've been jacking the back up high - which is a really good way to dislodge any trapped air pockets prior to a coolant bleed. The TF coolant Gods are smiling upon you :)
 
#4 ·
The other's behind the black plastic cover in the front under-bonnet area, ~1/3 of the way in from the right as you look from the front (if I remember correctly).
It's the heater matrix bleed point and has a brake-bleed-nipple type of connector that you loosen when hot/pressurised to allow air /water out then close up when there's no more air bubbles or spits.
(Try to get a plastic tube over the bleed nipple otherwise - as I found - :-( coolant runs down the inside, onto the matrix gets hot and smells...)
I'd personally bleed it after the rad and before the rear pipe (to any chase air bubbles upwards...)
 
#6 ·
Did it get warm before you changed the gearbox or is this car unknown to you before hand? Being a 53 plate car it's likely that it was fitted with a PRT thermostat with the original stat housing filled with a blanking ring, it's not uncommon to find some thinking the thermostat is missing and installing a conventional one in so the car ends up with two thermostats.
 
#7 ·
Thanks for all the replies. I bled the radiator and matrix today very little air in there. Was a good excuse for a test drive. In the summer the temp gauge sits at normal but today it only rose to just over 1/4 and it took a long time getting. The heater was blowing lukewarm there so I’m suspecting the stat?. The question is will the car be fitted with a PRT stat? and if so where is it and what is it like to change ?.
Thanks for all the support so far

James
 
#9 ·
Thanks for all the replies. I bled the radiator and matrix today very little air in there. Was a good excuse for a test drive. In the summer the temp gauge sits at normal but today it only rose to just over 1/4 and it took a long time getting. The heater was blowing lukewarm there so I’m suspecting the stat?. The question is will the car be fitted with a PRT stat? and if so where is it and what is it like to change ?.
Thanks for all the support so far

James


Hi James, as stated previously, your TF is likely to have the PRT. It is located just before the hose meets the underfloor steel pipes that run to the front of the vehicle. It is easily accessed from under the vehicle.

Regards

Tony
 
#11 ·
Perhaps one point which should have been covered James, was to assess the actual running temperature as opposed to the gauge indicated temperature. It could be that the operating temperature is actually fine, but the gauge sender unit may be playing up, and giving a false value to the gauge.
Apologies for the late afterthought, but....
Lets’s hope the now purchased thermostat is the offending party.
Kind regards,
Austin.
 
#12 ·
Perhaps one point which should have been covered James, was to assess the actual running temperature as opposed to the gauge indicated temperature. It could be that the operating temperature is actually fine, but the gauge sender unit may be playing up, and giving a false value to the gauge.
I did wonder that but it seems in the first post in the thread that the heater isn't that hot.
 
#16 ·
I go on o’clocks James.
My 2003 135 has always sat at 8 o’clock on the gauge even when the outside temperatures reached 30 degrees in the summer. As I understand it, these gauges are notoriously inaccurate/badly calibrated, and may not/unlikely to be a true indication of the actual running temperature. In other words, don’t necessarily expect the gauge of a perfectly serviceable, properly running coolant system to have a needle sitting at 9 o’clock.
If this were mine, I would be wanting to have it plugged in and road tested, so that you can accurately assess the running temperature and any variations from the norm.
Kind regards,
Austin.
 
#18 ·
Thanks for the input the digital gauge sounds interesting and might be an idea if I get the time. I took the car for a run today and the heater used to keep my legs warm with the roof down but it doesn’t seem to get as hot as it used to but it’s totally adequate if the hood is up. I noticed the oil temperature is reading around 70 degrees. I’ve never had a car with an oil temp gauge so not sure if this is normal or not ?
 
#21 ·
Hello James,
Simple things first:- oil temperature gauge reading? You can only assess the correct running oil temperature following at least a 10 mile run. It’s a common misconception that the engine oil is up to operating temperature once the coolant is - it isn’t. 70 degrees? Depends on how long the engine had been running and what the running speeds had been, but possibly around 100 degrees when up to full (in caps) operating conditions.
Sorry to be a bore James and repeating myself, but in full knowledge that these gauges are likely to be inaccurate, to me, it would be essential to know what the true actual running coolant temperature is before guessing and being concerned about anything. OK it may cost a small amount of funds, but you will then be armed with correct information to go forward with, rather than guess work. Everything might be just fine.
Kind regards,
Austin.
 
#24 ·
The gauges are not exactly scientific on these cars. But the heater should roast you once the cars up to temperature- ie, been running for say 4-5 miles. My TF160 has become more of an occasional user that it once was- but I still drop my son off to work saturdays and when he jumps into the car- he reaches for the dial to turn it down half-way. The temp guage by that time will be sitting just below half-way (9-o'clock) The distance between my house and Maidstone town-center being about 3 miles.
I had the oil-temp fail on me during the year- that read way too high and caused the oil-temp light to flicker! Fearing the worst, I slowed down to 60 (on the M25) as it was a long-journey to Sutton. I replaced the sender and problem solved- they are very simple designs.
 
#25 ·
For what it's worth, I fitted a digital water temp gauge that reads directly from the ODB2 port under the dash. It tells me exactly what is going on and how the temperature fluctuates under different driving conditions. I have made it a permanent fixture and it does not seem to cause any battery drain when the car is not being used.
It is similar to the AUTOOL X60 that sells on from various vendors on the 'net. It helped me pinpoint the exact situations when overheating is imminent.
B.
 
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