Overheating in the hot weather

MalcQV

Zorg Addict
British Zeds
Joined
Oct 30, 2018
Points
53
Location
Manchester, UK
Model of Z
1.9
Last Saturday the temperature went up into the red on the gauge (1999 1.9 140bhp).
There was fluid and steam coming from the lower part of the radiator. I have replaced the reservoir earlier this year but think it did still leak around the seal a little. I used a radiator seal to close it off which seemed to work.

I eventually after a couple of stops and top up, called the RAC because I was beginning to think the viscous/clutch fan may be at fault or worse the water pump. It seemed like there was coolant in the reservoir but it still overheated. I also noted no heat from the heater inside (air lock)
Whilst waiting for the RAC I knew there was a Tesco close by and bought four bottles of water, that in itself turned out funny as I bought sparkling water (read the label). Anyway I emptied four litres of fiz in the radiator and released the bleed screw.
Low and behold it was right again, cancelled the RAC and drove home. At home it was hissing again and I noted some fluid loss.

So what did I take from this?
  1. Water pump is OK
  2. I do once again have a leak. Damn reservoir or lower hose.
  3. It only overheats and loses lots of fluid when I am stationary in a queue and we are having exceptionally hot weather.
  4. It has not done it since, in fact I have used it all week for work which is a longer journey but less queuing and less hot weather.
I therefore thought maybe this viscous fan is also aiding an abetting the leak. Looking online it seems there should be some resistance to spinning it though it does not say whether hot or cold. There is, when it is cold (odd) but when it's at normal temperature it is free (as you would expect) but with some very slight resistance.

All that sounds like normal operation but it has always made a roaring sound from the cooling fan when you first start up on a cold morning or even a slightly warm one which does seem odd. I never checked the cooling fan when the needle approaches red because it should then have resistance. I could probably try that but am not keen

The only other thing I have not checked is the thermostat, perhaps it is stuck partially open?

Ideas and thoughts?
 

mrscalex

Zorg Guru (IV)
Supporter
British Zeds
3rd Party Trader
Joined
Jun 10, 2016
Points
165
Location
Swindon & Swansea
Well the over heating when standing still is classic viscous fan.

But it never hurts to do the water pump and thermostat if you don’t know when they were last replaced.

On a 2.2 the hoses can be ‘reconditioned’ if physically solid by replacing the o-ring. I’m not sure if 1.9s use jubilee clips though?
 

Faheem

Zorg Guru (III)
Supporter
British Zeds
The M44 Massive
Joined
Jun 9, 2016
Points
145
Location
Leicester
Model of Z
1.9 M44
@handsomejackuk Nope, it's only the ones with aircon that have the electric fan as far as I'm aware.
 

Ianmc

Zorg Guru (IV)
British Zeds
The M44 Massive
Joined
Oct 12, 2014
Points
165
Location
New Forest
Model of Z
Z3 (M44)
My early 1997 1.9 M44 doesn't have a viscous (or mechanical) fan from factory. The aircon (electric) fan does the engine cooling when necessary.:thumbsup:
 

MalcQV

Zorg Addict
British Zeds
Joined
Oct 30, 2018
Points
53
Location
Manchester, UK
Model of Z
1.9
Hey guys thanks for the replies. Been busy at work and not had a chance to check back. 32 mm open spanner and Viscous fan ordered. The thermostat looks brand new and I recall the previous owner commenting on it.

I will read that viscous fan link too. I always assumed it was a wax of some kind but if you think about it, wax melts with heat. There's a clutch in there somewhere too!
Indeed mine does not have A/C unfortunately, but then on old cars I personally have no luck generally with A/C. My last three daily's and all 5+ years old when I bought (latest is a brand new Mercedes CLA), all had A/C issues or more precisely leaks that seemed expensive or in the case of my CLK impossible to find. So I guess if I do not have it, it can't break and not work :D

A little story. Last weekend the we took the car out to a local (sort of) cafe/restaurant in Belmont near Bolton (we live in Astley) and whilst on the motorway it was fine but we ended up in a bit of traffic as we skirt around Bolton town centre. It got a little hot and the gauge rose a little but we arrived unscathed if a little hot so we parked up and left it to cool. After breakfast we went back to the cooled down car and left. When I use it for work (as today) and especially if it is a warm day and the roof down, I put the heater on full and the blower to compensate for the failing fan when stopped in traffic. It works but the missus is none too pleased so I cross my fingers (she is currently on a hate of this car) and leave it off.

Just as we are almost home (3 miles to go) it gets too hot and I have to stop to add water. Open the bonnet and remove the reservoir cap. Water leaks out when the pressure and heat is high from the reservoir seal I assume (will check that out this weekend, though as I said it is new) so there was little water in the reservoir and no danger of it spurting out like Mt Etna. I removed the bleed screw ready for top up. The bleed screw falls off the end of my screwdriver and drops on top of the cowling but near the vent/bleed. Before I can get it the ensuing steam pushes it down onto the lower engine cover. Can I find it? No, still have not found it and it may still be on the cover :sour:.

WTF do I do? No way will it do three miles without that vent screw. Searching around as I am near a small wood I find a soda siphon cartridge, those things we had in the 70's for fizzy cordial drinks but kids today are trying to kill themselves with, inhaling the contents. So I pop it in the vent hole and closing the bonnet just presses on it enough :D. We got home and I have until today left it on the drive.
New bleed screws arrived yesterday (I bought two) so I am in the car again today. Really enjoying the car and as I am on flexitime I can leave when there is little traffic, aided by the kids being off school and half the country seemingly on holiday.

I have a spare bleed screw but have kept the used cartridge as extra backup just in case :p
 
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MalcQV

Zorg Addict
British Zeds
Joined
Oct 30, 2018
Points
53
Location
Manchester, UK
Model of Z
1.9
The replacement viscous coupling seems to have done the trick. I can now hear it whooshing when the needle gets slightly above half.
If we get anymore hot weather that will tell the truth.

I did notice a date stamp on the old coupling 22/02/18. It has not been on long at all.
 
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