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sslim · Posted: Sun Mar 16, 2003 5:33 am Post subject: Boiling Coolant/Water

each time after running about 5-6 hot laps on the race track (constant redlining on every gear), my temp will go up to 90-100 degree, start boiling and lose coolant/water. have to go back to pits, cool the car, top up water before i can go again.

i have tried running almost 100% pure water without coolant or antifreeze, and the same thing still happens ..... Sad

but when driving on the road, i can run on the highway constantly at 160-180kmh for a couple of hours without any problem.

any idea what is the problem or what i can do to solve this problem? i am thinking of bigger radiator but it look impossible to do that on the 33 ..... Question

Admin · Posted: Sun Mar 16, 2003 12:34 pm Post subject:

Hi

Not sure, but one suggestion is to leave the heater on full when you are on the track. It is probably well worth cleaning the radiator out. For a first attempt you can try back flushing it yourself, but if that doesnt cure the problem then take it off and take it to a radiator specialist

All the best

KEith

neo · Posted: Sun Mar 16, 2003 5:14 pm Post subject:

Hi!

If the radiator is ok then try to drill a small hole on the thermostat so that fresh water is constantly runnig trough the engine. Then make a bypass switch on the radiator fan over a relay, and when racing keep the fan on all the time.

p.s. When I tuned a 900 ccm engine for racing (I placed a turbo on the engine), that solved my problem with overheating.

Luciano · Posted: Wed Mar 19, 2003 12:49 am Post subject: Re: Boiling Coolant/Water

Try more refrigerant, not less!!!!!!!!!!!!!!!!!!
_________________
Alfa Romeo Trentatrè Q4 '94

alexj · Posted: Wed Mar 26, 2003 12:31 pm Post subject:

If you try "more refrigerant (antifreeze?), not less", you will increase the boiling point, but you will also reduce the heat transfer properties of the coolant. Water has better heat transfer properties than glycol coolant.

If you are racing in an area where the night time temperature does not go below 0 deg C, then you don't need antifreeze - but you do need a corrosion inhibitor.

You might consider a product by Redline - called "Water Wetter"
http://www.redlineoil.com/redlineoil/wwti.htm

On the other hand there might be another problem. How much power does your engine produce..... from what you say, I assume it's the standard 33 radiator?

Luciano · Posted: Wed Mar 26, 2003 7:47 pm Post subject:

sslim · Posted: Wed Mar 26, 2003 8:09 pm Post subject:

"Not sure, but one suggestion is to leave the heater on full when you are on the track. It is probably well worth cleaning the radiator out. For a first attempt you can try back flushing it yourself, but if that doesnt cure the problem then take it off and take it to a radiator specialist"

i am in singapore, so the heater has been dismantled long time ago ......
flushed the radiator and coolant but still has the same problem Crying or Very sad

, i am going to remove all the hoses and check if there is any choking.

sslim · Posted: Wed Mar 26, 2003 8:13 pm Post subject:

i had tried just pure water with 1-2 bottles of waterwetter and still has the same problem Crying or Very sad

........ my car is stock standard, just an upgraded chip that's all

sslim · Posted: Wed Mar 26, 2003 8:20 pm Post subject:

ok now i am a little confused with the antifreeze thing, let me see if i can get this right .........

since water is best for cooling, wouldn't more antifreeze/less water cause the car to heat up faster?
but since more antifreeze prevents it from boiling, so the temp will go up to 100-110 as usual but it won't be boiling?

is it safe to run the car at that temp although it is not boiling?

alexj · Posted: Wed Mar 26, 2003 10:23 pm Post subject:

At 90-100ºC water should not boil, because water doesn't boil below 100ºC, but of course in a car engine there are likely to be hot spots in places like the cylinder head, which are quite a bit hotter than the 90-100ºC where the temperature sender is located. Temperature sender units can not always be trusted anyway.

Have you checked the radiator cap? The radiator cap increases the pressure of the cooling system (compared with a open system), which increases the boiling point.

Some people use a higher pressure cap on their race engines, but unless you have a modified engine and the rest of your cooling system is in top condition, it might be better just to try replacing your standard cap, which should be a quick and cheap thing to check.

When you open look under the bonnet after a fast run on the track, is the water coming out the cooling system overflow or someplace else? Do you have any leaks etc, that could be reducing pressure (and therefore causing boiling)?

Then maybe you should look at the thermostat. If you have a stuck thermostat that does not open properly when hot, the radiator can't do it's job....... but if the temperature is only 90-100ºC, then it seems the system is getting cooled, so maybe the thermostat and radiator are o.k.

Hope some of this helps.

alexj · Posted: Wed Mar 26, 2003 10:31 pm Post subject:

Admin · Posted: Wed Mar 26, 2003 11:16 pm Post subject:

Hi

For the best cooling just use water. Antifreeze will make it overheat more.

How has the radiator been removed? For example if you just ran the radiator pipe from the thermostat back to the water pump then a large amount of coolant is just going to flow around without ever going to the radiator

All the best

Keith

Dave s London · Guest

Can I suggest you look at the overheating posting from Mark Ash on 14th March on the other discussion list?
http://disc.server.com/Indices/20413.html
This appears to address the problem.
Dave
Minari 1.7 8v & 147 2L

alexj · Posted: Fri Mar 28, 2003 3:37 am Post subject:

Hopefully the other things Mark mentioned should address the problem, as checking/changing the head gasket is a major job compared to checking radiator, cap, hoses and thermostat etc.

I will reproduce Mark's message here....

alexj · Posted: Fri Mar 28, 2003 3:54 am Post subject:

Admin · Posted: Fri Mar 28, 2003 12:16 pm Post subject:

Hi

As the heater has a switch to turn off the flow of coolant through it then I would think it should be possible to totally block off the coolant pipes intended for the heater. The only problem would be the pipe up to the header tank. Maybe replaceing the heater matrix with a pipe with a restrictor in it (ie, just a tiny hole in the middle) would be the best solution

All the best

Keith

Lon · Alfasud Joined: 28 Mar 2003 Posts: 29

what fuel do you use: Octane 95, 98 or higher ?
This also changes the heating of the engine ( specialy when chip tuned )

What type of Chip is mounted in the ECU? (one that only adjusts timing or are there more adjustments made)

Where is the airintake ?
do you stil have the big black airfilter box, or an open (cotton) airfilter ?

alexj · Posted: Fri Mar 28, 2003 1:59 pm Post subject:

sslim · Posted: Fri Mar 28, 2003 7:19 pm Post subject:

sslim · Posted: Fri Mar 28, 2003 7:48 pm Post subject:

Rob - Perth · Guest

This might be a bit of an obvious answer, but seeing that you are in Singapore, why not take out the thermostat completely? You hardly need it for warming up from freezing conditions!

You could take out the t'stat, but not throw it away, give the car a try & decide then whether or not the thing is useful.

Cheers,

Rob

james · Alfasud Joined: 01 Apr 2003 Posts: 82

Admin · Posted: Wed Apr 02, 2003 12:08 pm Post subject:

Hi

Might well help (although it isnt so easy on the 33 with the thermostat being a sealed unit)

However watch out as on some cars is makes them run hotter (the Alfa 164 for example can suffer this). Basically on some cars the water pump cannot push the water round without the resistance to the flow caused by the stat

All the best

Keith

Gary UK · Posted: Sun Apr 06, 2003 12:17 am Post subject:

Are you posotive it's the water actually boiling and not combustion gasses getting through the head gasket at really high revs that is pressuring the system and forcing water out. These gasses would also make it run hotter as there would be less metal to water contact.

I was under the impression that the 33 sytem was not pressurised and any pressure in the system meant problems with the head gasket.

alexj · Posted: Sun Apr 06, 2003 7:57 am Post subject: