Grey Motor running Temperture

[jimmy]

Hi Guys

I run  temp gauge in my FC. Its seems to run what I think is hot (200 deg).  

Does anyone else run a temp gauge, and what temp does your run at ??

Thanks in advance.

JS.

[JB]

Hi Jimmy,

You must have oil in the radiator to get it that high.  

Mine muns between 75deg C and 85deg C depending on the driving.

Cheers
Jason.  

[gp]

Hi Jimmy,
I always think it's a mistake to run a temp gauge on an old Holden (There'll probably be a few people disagree with me). I find that it makes people worry about something that their car has always done, only they didn't know it. The first questions that I always ask are: Does it use water? and does it boil? If it does neither of these, then there's probably not a problem. Have you only just put the temp gauge on and changed nothing else? If so, then your car has probably always run at thet temperature. Another thing you should consider is, how do you know your gauge is accurate? Is it an old gauge, or is it a new modern gauge? You should also take into account where you have the sender unit.

Having said that, if your car is running too hot, you should try to do something about it.

Hope this is helpful.

Regards,

Graham Pryce

[slim]

I must be a little bit silly but 200 degrees   Doesnt it mean your boiling at 100 degrees.  Think the gauge is a bit dodgey personally !  Boiling at 100 degrees celcius that is , not ferenheit

[FCwagon]

Hi Jimmy,
An old Holden will run at about 180F with a 7lb radiator cap. If you've got a 13lb cap from a later model fitted it may bump it up to 200 or it may just be a dodgey guage you've got.
The radiator cap is like the valve on a pressure cooker - it allows the water to reach a higher temperature before boiling, the higher the blow off pressure of the cap spring the hotter the engine will run.
So if you're running a grey motor, make sure the cap is 7lb to help keep it cool.
cheers,
Leigh

[FC0058]

Hi Jimmy
I know what your on about. I took delivery of my FC about 3 weeks ago and it has a gauge and yes it was running at about 200+F/100c. I was very concerned so I took the following steps:

1. Check thermostat - mine needed replacing.
2. Flush radiator - I used loctite rust and scale remover.
3. Replace radiator hoses - Only if required.

Once you have done this fill with antiboil antifreeze.

I have run the engine since and it seems to be running at about 160f/70c. However I am yet to road test. I was hoping to drive down to the Gold Coast this weekend but all being as it is with an old car I have a bit of work to do before I make that trip.

My next step is a pressure test and put a kit through the water pump.

Just my thoughts.

[stevo56]

As per the other replies, its definitely in F not C. (celsius)

An old mech was visiting the other day and he saw the grey motor getting done up by me.
Some of the mods that they used to do were quite interesting. I'll invite him over foranother beer soon and get more details but one of the problems they had with hot grey motors was overheating.
A simple mod was to drill and tap the cylinder head on the manifold side (there's a cuppla flat spots on the head perfect for drilling) and run a pipe to the radiator.
No more hot heads.

Interesting old bugger, but he never brings a stubby with him.

[Effie C]

Stevo
Don't let him get away without tapping all that valuable information he is carrying within the grey matter.
Don't feed toomuch alchol as this kills the brain cells,looking forward to long lost grey motor hot up info posting.
John M

[nicko]

my old FC had very hot grey and used to run about half on the smiths temp guage as i got a 3 core in the old FC bottom and top tanks , looked original if you did not look to close

[stevo56]

I think the old bastrad has already had too much to drink, but I'll write down all he has to tell and post it as I go.
Maybe, if he has enough good stuff to tell, I can be like Slim and have my own section. Haha Just teasin' ya Slim.
(refer some other post re Slim's separate for sale section, in case you were wondering what I'm gibbering about)

[RET]

Getting back to the original topic, my grey motor just did 1,483 miles to Gold Coast and back.  I fitted a gauge to it before I left, and it ran at 170-180F for the entire trip, and not once did the radiator require topping up.  Standard 7lb cap, BTW.  If that's not optimal, it must be close!

Now oil consumption, that's another story

cheers
RET

[ChrisB]

re hot temp,
like GP says, I fitted a gauge and then went down the track of thinking it was getting hot, got the experts to put a infrared heat gun on the system. result was interesting, radiator and motor were fine, the gauge was fine too, the heads on the grey run 10 deg C hotter at the back, hence my concern. I run a 71 deg C t/stat and all was well. It was interesting to see the cooling system operate and watch temps change across the system.
Moral to the story,  if it aint broke dont fix it !!
do you believe this ? I dont, If your concerned at all get it checked but remember the sender is at the back of the head and will always be hotter than you think

my old bus sat between 80 and 90 deg C all the way to QLD, shame about the oil though !!

Cheers ChrisB  

[mcl1959]

Jimmy,  first I would say 200 is too hot - 180 is the ideal.

But as others as have said - do the following roughly in this order to minimize wasted money.
Check cap is 7 lb non recovery type
Check bottom radiator hose has a spring inside it as without one, the hose will collapse on itself when hot and restrict flow.
Check thermostat is OK - probably best to replace if unsure.
Check guage is accurate - once again replace if unsure.
A simple test I did recently was to put a couple of thermostats in a pot of water and set up 3 guages to find what was working or not.
Boil the water and you will see the thermostats open and at what temp they open.  By having 3 guages you can work out pretty effectively what's working & what's not.
If after the 4 steps above the temp is still hot, then do the following;
Flush the block - this is best done by removing the manifolds and taking out all the welsh plugs in th eside of the block (not very expensive to replace- about $15.  And you will be surprised how much gunk is in there if it is a fairly old or origianl motor)
Have radiator reverse flushed and a report from the radiator company - it may need the core cleaning (approx $60) or a new core(approx $200)
Replace the water pump with a new one if it is old.  Use a cast iron impellar rather than the cheaper pressed metal impellar (it works better)
After this your cooling system should be in tip top condition.
Then throw the guage away & don't worry about it anymore.

[gp]

and so say all of us!

Regards,

Graham