A few posters have mentioned doing this and I reckon it's wise with Winter approaching .These vehicles are ridiculously over cooled to the point it can take 15 minutes or 5-8 miles to reach full operating temperature .Id say there's a minimum 1-2 mpg saving in fuel to be made ( and your interior heater will work faster too ) Just be careful the sheets of cardboard , wooden or rubber placemats , plywood etc don't come loose and do harm .If you're a regular city driver might be best not to bother either but I've never seen my MJ overheat except for a brief moment when fan belt snapped ( and I immediately turned off engine ) Not sure I've even heard engine fan EVER run .And I now keep fluid level at a cm or two UNDER minimum .
Technical Blanking off Half of Radiator in Panda Multijet Diesel
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Technical Blanking off Half of Radiator in Panda Multijet Diesel
What's this winter thing you're talking about??? On a 'normal' year, I'd be changing over my wheels to my steels with the winter tyres now. However this year it's still way too warm to consider a swap!
Yeah apparently we had warmest day ever in November at 20.1 degrees last Sunday ,)previous record was 20 degrees in 1947 I think so hardly a global warming catastrophe )
Fuel consumption definitely varies throughout year although I'm not sure it's quite as simple as hotter =higher , colder =lower .I reckon humidity etc might be an issue also and wind obviously etc
Fuel consumption definitely varies throughout year although I'm not sure it's quite as simple as hotter =higher , colder =lower .I reckon humidity etc might be an issue also and wind obviously etc
Its still far too warm now but I've done this on my cars for years when it gets cold, car warms up faster and probably does the engine some good too.
Not sure there's anything to be gained by blanking it off. The thermostat will only open at a set temperature, the radiator isn't in play until then.
Sweetsixteen
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That's a part of the problem.
With the radiator not getting any warm water from the engine block because the thermostat is shut, the result is that freezing air (if the weather is freezing) is blowing right through the radiator unhindered. In bad conditions this can allow the lower portion of the radiator to actually freeze, even if antifreeze is present. Not good. Meantime, your engine is running at lower-than-optimum temperature, struggling to get high enough to open the stat. Remember, the block is also being hit by freezing air. It all takes longer than it should, with the result that you have a cold car, higher fuel consumption and greater engine wear.
On the Panda there is a lower air intake below the bumper. I have this blanked off all year. It helps keep the radiator at an even temperature top to bottom, and stops the above possibility from happening.
Why not? All UK cars are very much overcooled.
I'm not sure that's right. If the lower part of your radiator froze, it would burst.
The car doesn't struggle to reach operating temperature, it just takes longer as the ambient temp is lower.
The car doesn't struggle to reach operating temperature, it just takes longer as the ambient temp is lower.
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unless you have a lazy thermostat I can not understand what difference blanking makes as HP said, until the car is warmed I thought the thermostat blocked flow to the radiator?
In current temp my car is warm in a really short distance then stays there, never moves in all types of traffic.
I have blanked the panda before as i knew the thermostat was bad and it just wouldn't heat up properly and i didnt have the time to do it. After I changed it though, never ever a problem.
In current temp my car is warm in a really short distance then stays there, never moves in all types of traffic.
I have blanked the panda before as i knew the thermostat was bad and it just wouldn't heat up properly and i didnt have the time to do it. After I changed it though, never ever a problem.
Fiat spent thousands - ok, well, maybe tens of pounds designing the cooling system. Blanking off part of it isn't a good idea. Petrol or Dddddiesel, if this makes it warm up quicker, something else is broken, sorry.
Diesels always take longer to warm up. A diesel engine is subjected to higher compression loads, so the pistons, con rods and crank are stronger, and so heavier. The block also contains more metal, so it all takes longer to warm up. Add in to this the fact that diesel fuel burns at a lower temperature than petrol. So every diesel will take a long time to warm up in winter, as it does in summer. The only way to improve this is to put it in a heated garage overnight.
As said above, blanking the radiator will not affect how long it takes for it to warm up, but could cause problems later. This practice dates back to the twenties and before when cars had unpressurised cooling systems and no thermostat, so the water circulated all the time.
As said above, blanking the radiator will not affect how long it takes for it to warm up, but could cause problems later. This practice dates back to the twenties and before when cars had unpressurised cooling systems and no thermostat, so the water circulated all the time.
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I am not overly familiar with the Multijet diesels, but it's very common for manufacturers to include heat exchangers to the oil filter housing to aid oil cooling.
Some run off a small thermostat, just like the main one but instead of opening up the rad, it sends coolant around the oil filter housing.
If this small 'stat is stuck open or leaks past it will cause the engine to run a lot cooler and make it struggle to reach proper operating temp.
It's a very common issue with vehicles fitted with Fords 2.0 and 2.2 TDCi's (Duratorq), owners complain the gauge won't pass 1/4 mark and cabin's won't heat up no matter how far they drive or how long the motor's been running as it not only cools off the oil when it isn't needed but leaks off the warming coolant around the engine block and so it leaches cold coolant back in the jacket, slowing the warm up further.
On the ford cars on the back of the water pump is a small 'stat with a very small pipe leading to the oil filter housing and for a couple of quid to swap it out sorts the problem.
I wonder if the 1.3 MJ has something similar that could give the same result?
Some run off a small thermostat, just like the main one but instead of opening up the rad, it sends coolant around the oil filter housing.
If this small 'stat is stuck open or leaks past it will cause the engine to run a lot cooler and make it struggle to reach proper operating temp.
It's a very common issue with vehicles fitted with Fords 2.0 and 2.2 TDCi's (Duratorq), owners complain the gauge won't pass 1/4 mark and cabin's won't heat up no matter how far they drive or how long the motor's been running as it not only cools off the oil when it isn't needed but leaks off the warming coolant around the engine block and so it leaches cold coolant back in the jacket, slowing the warm up further.
On the ford cars on the back of the water pump is a small 'stat with a very small pipe leading to the oil filter housing and for a couple of quid to swap it out sorts the problem.
I wonder if the 1.3 MJ has something similar that could give the same result?
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On older cars, with a fan driven by a fan belt (talking pre 1980s here), because the fan was always spinning, and spinning faster with higher engine speeds, you could, just about, over-cool the radiator in winter. But with modern electric fans that only come on if they need to (when another thermostat turns them on), there really is no point to block the rad. Much more likely to cause damgae through overheating rather than gain any benefit.
The radiator at the front of the car does not affect the heating inside the car. Water circulating around the engine block also passes through the heater 'matrix' inside the car, irrespective of the engine temperature. So once the engine is warm, the heater can deliver warm air but until then its cool.
When the engine becomes over-warm a thermostatic valve opens and allows the circulating water to also pass through the radiator at the front, where it is cooled by air coming in through the grille beneath the number plate, and by the fan if the car is stationary. The thermostat will close again once the water cools. This process repeats as necessary to keep the engine at a constant temperature, once its warmed up.
The reason a diesel takes longer to warm up is because its a big lump of metal - heavier and thicker than the engine block of a petrol car. But, once its warm, it needs the full radiator - that;s why Fiat put it there.
The radiator at the front of the car does not affect the heating inside the car. Water circulating around the engine block also passes through the heater 'matrix' inside the car, irrespective of the engine temperature. So once the engine is warm, the heater can deliver warm air but until then its cool.
When the engine becomes over-warm a thermostatic valve opens and allows the circulating water to also pass through the radiator at the front, where it is cooled by air coming in through the grille beneath the number plate, and by the fan if the car is stationary. The thermostat will close again once the water cools. This process repeats as necessary to keep the engine at a constant temperature, once its warmed up.
The reason a diesel takes longer to warm up is because its a big lump of metal - heavier and thicker than the engine block of a petrol car. But, once its warm, it needs the full radiator - that;s why Fiat put it there.
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That intake below the bumper is the only intake... the upper 'grille' abouve the number plate is not actually 'open' to the engine bay at all - try looking through it .. its just 'for show', and allows noise from the horn to get out
Sweetsixteen
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That intake below the bumper is the only intake... the upper 'grille' abouve the number plate is not actually 'open' to the engine bay at all - try looking through it .. its just 'for show', and allows noise from the horn to get out
Yep, you're quite right. But its main purpose is not so much to allow the horn to be heard, but to channel air to the inlet tract, so it's not 'just for show'.
As my Multi runs all year round with the lower grille completely blanked, and never shows any sign of overheating, this just reinforces the fact that UK cars are overcooled. I say UK, because Pandas shipped to hot countries (I lived for years on an island off the African coast with temperatures regularly over 40 degs, and now spend some of each year there) have the identical cooling system, and cope with far higher temperatures with no problems.
They aren't overcooled at all. They have a capacity to deal with higher ambient temperatures, nothing more.
Are you aware that your temperature gauge isn't accurate? They sit in the middle to stop people panicking, variations of 10-15'c don't show a change. It will only lift if you are overheating.
If your car has air con, you know you need air flow to the system too?
Are you aware that your temperature gauge isn't accurate? They sit in the middle to stop people panicking, variations of 10-15'c don't show a change. It will only lift if you are overheating.
If your car has air con, you know you need air flow to the system too?
Sweetsixteen
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Yep - but a capacity to deal with higher temperatures without overheating also means that there is an over-capacity when dealing with colder temperatures. You can't have one without the other. Try asking any owner who grouses when the heater doesn't warm up in extreme cold weather!
The heater runs cooler because more of the energy from the fuel is spent on trying to get the engine up to temperature in bitter weather, while less is used in actually running the engine at its optimum temperature. Result? Cold feet, less efficient engine running, more fuel wasted. We all pay, one way or another.
What is the big deal against governing the blast of bitter air hitting, not just the radiator, but the whole engine block and its components under those condfitions?
The panda cooling system is primitive and typical of systems designed 30 years ago. Modern cooling systems have manifold heat exchangers to quickly warm the coolant, and active airflow control through the engine compartment to manage underbonnet temperature and allow the engine core to heat up faster.
It's nothing to do with airflow through the radiator; that's irrelevant to the warmup time as the thermostat will not allow coolant to flow through the radiator until the coolant reaches operating temperature. What matters in determining the warmup time is controlling the flow of cold air through the engine compartment, something which the standard Panda cooling system does not do.
I'd agree that blanking the radiator itself is pointless; but blanking the grille, especially the part that's not in front of the radiator, will significantly reduce the warmup time.
The engine is massively overcooled for the UK winter climate. It's designed to cope with the worst case scenario of hard driving in a southern european summer.
Airflow through the front grille is not relevant as far as the A/C system is concerned; cabin air is never taken from the engine compartment due to contamination issues; that's what the vents below the windscreen are for.
Cars with modern cooling systems incorporating manifold heat exchangers and active airflow management will typically warm up in about half the time of a Panda.
I did some experiments with blanking the front grille the first winter I got my Panda; I managed to achieve a significant reduction in the warmup time, but you do need to be careful not to let underbonnet temperatures get too high as you might damage the wiring and electrical components. Don't just rely on the temperature gauge as that is only measuring the coolant temperature. You would have to try very hard indeed to get the coolant to overheat; but my initial trials showed that underbonnet temperatures get excessively high long before this point, so do be careful if you are going to experiment - a fried ECU will cost you much more than any fuel saving you might make.
On cars used mainly for journeys <10 miles in a typical UK winter, improving the efficiency of the cooling system will likely get you a substantial improvement in both fuel economy and engine wear.
The real problem is that the cooling requirement during the warmup phase is completely different from the cooling requirement once at operating temperature; without some kind of variable geometry airflow system, you can't optimise both.
Front grille flaps, adjustable from inside the car, and a suitably located underbonnet temperature gauge, would make a good DIY project.
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Sweetsixteen
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Wondering where this info came from?
Every now and then I check my temperatures under the bonnet. I do this immediately after a journey, engine still running and everything thoroughly warmed up. With an ambient of 10degs it is currently reading 88.7degs, with other engine parts and components reading less (timing chain cover 82.4, common rail 42.3, etc) and this has varied very little throughout the year, even though ambients have varied by as much as 20degs.
I have no reason to doubt its accuracy, even though it does not state specific tremperatures. I am looking forward to checking engine temperatures when we get a spell of minus figures during the winter, by way of comparison.
Plenty of mis-information there guys. End of the day, do what makes you happy.
