Overcooling Astra...blanking off radiator

[ianess]

On another post [concerning gunge in the oil] one of the replies suggested blanking off part of the radiator to help the engine run hotter, thus avoiding "over cooling".
Exactly how do you go about doing this, and do others recommend the practice?

[dilligaf]

Lift the bonnet and see if there is a gap between the front of the rad and valance (the bit where the bonnet lock fits into) if so thy slipping a piece of cardboard between them to blank off the rad. Try a small section first, about one third. Keep a close eye on your temperature gauge and make sure the cardboard is secure.
Next bit is trial and error to decide how much to blank off.


Good luck.

[stanleyman]

You shouldn't need to do this if your thermostat is renewed for a high temperature one as it won't make any difference to a cold rad with no flow. It can also cause overheating when you least expect it. Giving the car a good long hard run once a week to heat it up properly will sort this out provided the coolant is not leaking into the engine. Fitting a grill muffler can help reduce cold air flowing over the engine to maintain temperature without affecting the rad too much in really cold weather and is easily adjusted or removed in warmer weather.

[calibrax]

I wouldn't recommend using a piece of cardboard... unless you cover it in tinfoil first. Cardboard on it's own could catch fire... It's unlikely, I know, but simply not worth the risk for the sake of a sheet of bacofoil!

[Toureman]

Hi ianass,

It was me that suggested blanking of the radiator.

Like the other driver you make it hard for people to answer questions because you do not give full details of your car!

Again, if your car falls into the same model range as my Astra it is easy to fit a blanking plate, If you slide a peice of waterproofed card into the gap just in front of the radiator it will just sit there and never move.

Mine was permanantly in the car for 4 years and never caught fire!

Changing the thermostat is cheap but unless you are a competant mechanic it would have to be done in a garage if you can find the right sort of thermostat, it is a lot easier and cheaper to use a blank.

with a different rating thermostat this might have to be changed every 6 months, winter and summer!

[dilligaf]

Please tell me CALIBRAX how a piece of cardboard in front of the radiator can catch fire, unless it's from a discarded fag end thrown from the car in front.

I used a bit of card for many years on an MBG with no ill effects. Just rember to remove it before a long journey in summer. I later discovered in those days the cooling fan consisted of four blades made up of two pieces of metal bolted onto the water pump pulley. Taking two blades off helped.. In winter the other two were removed and the car ran quite happily without a cooling fan at all. I doubt if you can do this with the modern car.
It may be worth investing in an electric fan which only cuts in when working temperature has been reached. , A company called Kenlowe used to make them, but I don't know if they still exist.

Whatever you opt for it will save you a few bob in fuel costs if you can get your engine up to max temperature asap.

[ianess]

Thanks for that Toureman. Yes you guessed right, I do have an Astra [1.6 automatic estate] and the temp gauge never gets up to normal unless it's laden and working hard. The rest of the time the needle sits very low even though the heating system works fine.
Thanks again.

[stanleyman]

Your temperature guage may just be out of adjustment and any attempt to raise the reading could cause overheating. Fit a new thermostat and see if it is the same before altering other things unnecessarily.

Blocking the rad off stops it from working properly when it really needs to, such as on a motorway, you can't stop to take it out!

[ashthesparkie]

Go to ebay and search "vauxhall thermostat fix" this will solve your problem, this is very common but now there is an answer. cardboard doesnt work!!

[ashthesparkie]

http://www.vauxhallop...rmostat.talktalk.net/