The local radiator shop told me they are cheaper work better and look better
My old v8 wb used to over heat with ac on that was a factory set up but always wondered if the ac was set up properly as it never seemed cold enough
The local radiator shop told me they are cheaper work better and look better
My old v8 wb used to over heat with ac on that was a factory set up but always wondered if the ac was set up properly as it never seemed cold enough
I've learnt some good lessons on cooling systems in my day job and i think the theories translate from diesel engines to petrol. The entire system should be balanced to maintain correct engine temperature for a wide range of conditions. The radiator, pump, thermostat, coolant and fan should all be considered part of the equation. Taily is right, the engine shouldn't be overcooled as it will suffer adverse effects. One more comment is to keep the coolant fresh and maintain a 50/50% mix of glycol and water. The glycol lowers the freeze point to around -36 Degrees C but it also raises the boil point in coolant, typically to around 106 Degrees C. This is further aided by a correctly fitted pressure cap with the best matched pressure rating which also helps raise the boil point.
I have always wondered what is the point of pressurising the system is if anyone can explain it would be good does it raise the boiling point much ? ,a system I though ran under 15 psi which is not much pressure
Hi Beachy. Each engine manufacturer will specify the cooling system pressure required and this is most appropriate to modern engines where coolant temps can range up over 100 deg C without issue. The key is for the coolant to not boil, so pressure plus glycol is used to keep things under control. As far as pressure goes, generally its as simple as getting the correct cap for say a 308 and things should be ok. With coolant, there are two important service points. One is to ensure the 50/50 mix which can be checked instantly usuing a refractometer, the other is end of life checking which is the acidity of the coolant. Over time, the engine combustion process will degrade the coolant until it goes too acidic. A simple PH test will indicate if the coolant is 'off' and thus a flush and new coolant are called for. You also need to keep the overflow bottle in play as it allows the system to 'breath' during its operation. Hope this helps.Originally Posted by Beachy
Increasing water pressure increases the boiling point. As has been pointed out,the hotter an engine runs the more efficient it is and the less wear and sludge build up. That's why taxis do a million km without a rebuild but grandpas HZ Kingswood only did 45000km and was burning oil and was a sludged up mess under the rocker cover.
It's also why you lose the lobes off the camshaft on 308/253 from short running. Lots of cold starts.
Are the aluminium ones better or just cheaper because they are made in China? Dirt bikes use them because they are lighter. But the whole engine is alloy so no corrosion issues. Won't an alloy rad have corrosion issues like the alloy manifolds?
Coolant does funny stuff, have a look at the pin holes cavitation causes on the sleeves in a diesel motor.
The overflow catches the coolant as it expands when you turn the engine off air flow stops through the radiator. Then when it cools the coolant contracts and sucks it back into the radiator.
Last edited by wbute; 07-09-2015 at 10:07 PM.
Nice reference to Diesel engine liner cavitation WB. My favourite subject!!!! Our Cummins K50 engines at work suffered horribly from this in the early years.
An old Chamberlain we had with a John Deere engine it let go from it. Took about 9000 hours though. One sleeve was hammered in one spot. Looked like a sandblaster had been at it. Got another old Chamberlain that blows head gaskets because the sleeves have sunk down on the o-rings. I have replaced the head gasket twice now mainly because it's cheaper than rebuilding and machining the block to fix it.
Cooling systems are more of a "system" than is realised as you said. It should be fairly straight forward to get a V8 Holden right. I never saw too many issues with the Cat 793 trucks I drove at Cadia. They were 2700hp V16 operating in temps from below zero to over 40. Running out of the pit under full load for 30 minutes to get to the top! That was a real eye opener for me.
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Last edited by wbute; 07-09-2015 at 10:43 PM.
Thanks for all the interest and info supplied. The reason I was going with an electric fan was because the front end had a terminal meeting with a Commodore some 17 years ago and the fan and cowling was unserviceable.....along with some other parts. The water pump is new and the V8 alloy rad was the cheapest option. The radiator is 'insulated' from the metal support via rubber and non metallic washers so I am hoping to avoid any electrolysis. Either way is an overflow bottle a necessity ? Once again thanks for all the interest and replies. Being in Perth it needs to be tip top. Will only be cruising with not too many burn outs
If you need to get rego you might need an overflow bottle
I got rego (over the pits) with out overflow bottle in WA
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