ZX: running cool(generally 70 degrees)

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
ZXturbo_Aura
Posts: 148
Joined: 10 Oct 2003, 02:56
Location: United Kingdom
My Cars:

ZX: running cool(generally 70 degrees)

Post by ZXturbo_Aura »

keeping to a constant 65mph, my ZX TD is running at about 70 degrees C, does this seem a little low/cool?i thought it should be around 80ish??? any points?
Dan
Jon

Post by Jon »

Soudns far too low to me fella, mine sits just under 90 degrees on the gauge on the m-way. As did the last 2 ZX TD's I've owned.
Its definately fully warmed up?
Usual advise, try replacing the thermostat first.
ZXturbo_Aura
Posts: 148
Joined: 10 Oct 2003, 02:56
Location: United Kingdom
My Cars:

Post by ZXturbo_Aura »

im stumped, its had a new thermostat, water pump was done 2k ago when i did the belt,it was flushed 4 weeks ago and completely bleeded, although i noticed earlier today that the botom of the rad was stone cold whilst the top was quite hot, the top hose from the thermo housing feels pressurised and is hot, any other suggestions???if its let to idle, it will reach just below 90 and sit there,
Dan
User avatar
AndersDK
Posts: 6060
Joined: 21 Feb 2003, 04:56
Location: Denmark
My Cars:
x 1

Post by AndersDK »

Despite the new thermosts - all your explanations clearly points to a thermostat leaking past the coolant before it's actually hot.
It happens if the gasket is failing/missing - or the new thermostat simply won't keep closed at cold [:(]).
test it :
From cold engine - start engine and let idle - with a hand on top corner of radiator where large top hose goes in.
This is the point where the rad is feeded with hot coolant from emgine - and this point should STAY stonecold the first several minutes (outdoor temp depending) with engine idle - then suddenly (!) raise in temp untill you MUST let go your hand - indicating engine has reached working temp.
If the rad clearly starts sloooooowly heating up for long soon after engine start - then the thermostat leaks.
Russell
Posts: 102
Joined: 20 Jan 2004, 03:15
Location:
My Cars:

Post by Russell »

Might be worth taking the temperature, maybe your gauge is reading low. Also, when the temperature is as high as it get's, can you hold the top hose while wincing or is it way too hot..? (A little bit of caution here, don't hang on and burn your hand!!)
I'd have thought coolant at 70 degress inside a rubber pipe would be about the top limit one can touch, but 80 or 90 degrees is going to be just too damn hot [}:)]
cheers
Russell [:)]
User avatar
TomH
Posts: 267
Joined: 23 Nov 2003, 03:59
Location: United Kingdom
My Cars:

Post by TomH »

my temp always sits between 70-80 unless I drive hard and then it is still below 90! Never considered that abnormal though.
dieseldan
Posts: 16
Joined: 16 Feb 2004, 03:04
Location:
My Cars:

Post by dieseldan »

Dan,
Are you using a citroen thermostat cos I replaced a themostat on a car about 2 months ago with a patent one and it was still running cool. I began suspecting other things but eventually I bit the bullet and bought a OEM one, the car ran perfectly after that.
Dan
(94 ZX Volcane TD)
User avatar
rabenson
Posts: 328
Joined: 15 Jul 2002, 15:14
Location: Northallerton, N Yorks. UK
My Cars:

Post by rabenson »

I wouldn't worry too much about absolute values, as Russell says above, your gauge could be reading low. Has it always been around this level or has it recently changed? Try letting it tick over with heater off and note at what indicated temp the first cooling fan cuts in.
Ron
Guru Meditation
Posts: 259
Joined: 18 Dec 2002, 02:30
Location:
My Cars:
Contact:

Post by Guru Meditation »

My 2p my ZX TD runs at just below 90-85+, when working hard will creep up to just above 90 then will drop back down.
ZXturbo_Aura
Posts: 148
Joined: 10 Oct 2003, 02:56
Location: United Kingdom
My Cars:

Post by ZXturbo_Aura »

hi,
thanks for the replies, i'll be trying then later on, in college at the moment...
i replaced the thermostat about 4 weeks ago with a genuine citroen part, an flushed the sytem well, it only seemed to start running cool in the last 2 weeks say, im hoping it isnt the head gasket!!havent got a lot of time to do it!skimming aside, its about a days job am i right?
DAn
thanks again
Simon Canfer
Posts: 114
Joined: 02 Mar 2001, 17:41
Location: United Kingdom
My Cars:

Post by Simon Canfer »

The head gasket might be possible in a long day if you're experienced and have the tools; for example if you can do a cambelt change in no time flat!
Then there's the issue of checking the head for flatness and possibly needing it skimmed, and I seem to remember there are different thicknesses of gaskets fitted.
Simon Canfer
ZXturbo_Aura
Posts: 148
Joined: 10 Oct 2003, 02:56
Location: United Kingdom
My Cars:

Post by ZXturbo_Aura »

im very suspicious of the head gasket, found a small trace of oil in the coolant before and also there a sometimes small bubbles in the coolant when idling, im hoping it will last till the summer when i have the time to do the head, get it skimmed etc, i intend on keeping the car for atleast 2 years so im prepared to spend time and money...
but untill i do the head... i will have it pressure tested and just keep my eyc on it for now, thanks greatly guys(and girls!!),
DAn
alan s
RIP 2010
Posts: 2542
Joined: 26 Jan 2001, 15:53
Location: Australia
My Cars:
x 6

Post by alan s »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by ZXturbo_Aura</i>

im stumped, its had a new thermostat, water pump was done 2k ago when i did the belt,it was flushed 4 weeks ago and completely bleeded, although i noticed earlier today that the botom of the rad was stone cold whilst the top was quite hot, the top hose from the thermo housing feels pressurised and is hot, any other suggestions???if its let to idle, it will reach just below 90 and sit there,
Dan
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
These symptoms still point to you having a faulty thermostat. I know you said a new one was fitted but years ago I worked for a Toyota dealer & I had a mechanic going off his nut trying to figure out why he couldn't get a car to run to temperature.
He had replaced the thermostat so it was right.....well it had to be right!! Wrong; he eventually tested the thermostats as he took them from the box & before he fitted them to the car (after having a repeat dose when he fitted another new one) only to find a complete box of 20 new thermostats bar 2 or 3 were all faulty.
Doesn't happen all that often, but does happen & it is hard to detect.
Take the thermostat & place it in a pan of water; bring to the boil. If it opens before it boils; it's stuffed!
Another thought too; same symptom would apply if you had an electrical problem and the fans were running continuosly or cutting in too early. We find in one of our BXs that when the air/con is operating, the engine temp always stays low regardless of the ambient temperature or the load from the air/con compressor.
Alan S
tony1
Posts: 23
Joined: 02 Mar 2004, 14:20
Location:
My Cars:

Post by tony1 »

On my 1.9I I fitted a halfords thermostat which was a different design to the original one and the first time it fully opened it jammed against the engine casting and remained open. Not sure if this could apply to a TD engine.
Crossman
Posts: 20
Joined: 27 Sep 2002, 02:19
Location:
My Cars:

Post by Crossman »

Hi all,
I've got a ZX 1.9TD Volcane and my temperature runs at about 70 degrees unless I (rarely) give it some stick, or up steep hils in which case it goes up to about 80 degrees and then promptly returns back to 70 degrees when driving normally. I've checked the radiator a couple of times over the last year and the stats not stuck open, as the radiator gets hot all of a sudden. I can only presume that the stat is opening to soon or the gauge (or sender) is inaccurate or faulty.
I have a mate who has a 306 DTurbo, 405TD and my old 309 TurboD all ran at about 90 degrees so I presume this is the correct temperature but without further investigation I’m not sure what it is, but the cars given me nearly 3 years of relatively trouble free motoring so I'm just going to leave it unless I fancy tinkering.
Crossman.
Post Reply