Can the Grill & Radiator be Painted? What paint is best?

[Bangorbob]

I cleaned the bugs out of the grills on my 20 RTL. Can the grill and radiator be painted? If so, what type of paint is best for this?

[BLUEKNIGHT911]

I cleaned the bugs out of the grills on my 20 RTL. Can the grill and radiator be painted? If so, what type of paint is best for this?

I did mine 6 or 7 years ago with reg .Flat Blk. spray paint..... it's looks the same as when I painted them .... The radiators won't get a Temp. more than 212 F ...... Mike

[spyderdave]

Two years ago I pulled the whole front module and painted both my radiators. I thought an enamel might go on thick and, perhaps, affect the cooling ability of the fins, so I used a good quality flat black laquer; just a couple of light coats.

[Bangorbob]

Thanks for the responses. I just wanted to make sure before I made a possible costly mistake.

[Mikey]

Thanks for the responses. I just wanted to make sure before I made a possible costly mistake.

Are you thinking painting your radiator will help with the cleaning of bugs better?

[Bangorbob]

Are you thinking painting your radiator will help with the cleaning of bugs better?

Heavens no! I just like seeing silver or whatever color it is. Because the front is black thats what I want to see.

[WRCLVR]

IIRC black will radiate heat better. I'd use very thin coat.

FYI we used to paint our VW aircooled engines and found out the hard way to paint the finned cylinders, oil cooler and finned heads ...black. Rest could be any colour.

[IdahoMtnSpyder]

I would not paint the radiators. Grills would be OK. You're sure to affect the heat transfer capability, although maybe not significantly. However, a metal to air interface is not a great heat transfer medium to begin with so it would be best not to compromise it at all. The color of paint should not be a real factor since the heat transfer in a radiator occurs mostly by direct air to metal contact and radiation over a very short air film thickness. Color mostly affects radiant heating/cooling heat transfer. Heat transfer is not a simple engineering issue.

[Bangorbob]

Thanks to all. I ordered and received the kott grills. I painted them today and will install tomorrow. I left the rad and grill alone. And I also know that the kott grills will not keep all the bugs out. I do know they will make smaller ones out of bigger ones.

[K80Shooter]

Thanks to all. I ordered and received the kott grills. I painted them today and will install tomorrow. I left the rad and grill alone. And I also know that the kott grills will not keep all the bugs out. I do know they will make smaller ones out of bigger ones.

I got a couple of these to go just behind my grill covers. They should stop most anything and still let plenty of air through them.

https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

[Peter Aawen]

I got a couple of these to go just behind my grill covers. They should stop most anything and still let plenty of air through them.

https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

Maybe it's hotter where I am in Oz, but adding ANYTHING to the KOTT grilles (even what appears to be exactly the same woven wire mesh as yours K80! ) caused my Spyder to run somewhat hotter all the time and to occasionally shut down due to over-heating - so it didn't last long, nor did anything else I tried! Mind you, like most modern vehicles, the Factory Temperature gauge has been purposefully damped by the factory to keep the punters happy and unaware of what's REALLY going on (your coolant temps WILL be going up and down as the engine load & speed etc. increases/decreases, and as the thermostat opens/closes, but your temp gauge won't show that, cos you might not understand that it's meant to do that!! So it rapidly gets up to and then sits about halfway up the scale... supposedly fooling you into thinking the temp never moves when they are really changing all the time!! ) so that you can't really tell from that if your temp has increased a lot, often until it's too late you really need a more accurate un-damped temperature monitor to show you what's TRULY going on with your temperature!

The Cooling Specialist who used to look after my hard-working Desert & High Country 4WD Tour & Exped Support Trucks advised that even adding the KOTT grilles would be reducing my Spyder's airflow somewhat, and while I could get away with just fitting them because they cause only 'a little' reduction in airflow, the Spyder's Cooling System was really JUST adequate at best (even with WaterWetter! ) so reducing the airflow any further by adding a finer mesh or anything else was quite risky, and he strongly advised against painting the radiators (due to the reduced temperature dispersal that results - there's a reason modern alloy radiators aren't painted ) or adding anything more beyond the KOTT Grilles (due to the previously mentioned reduced airflow)!

Just Sayin'

[BLUEKNIGHT911]

Maybe it's hotter where I am in Oz, but adding ANYTHING to the KOTT grilles (even what appears to be exactly the same woven wire mesh as yours K80! ) caused my Spyder to run somewhat hotter all the time and to occasionally shut down due to over-heating - so it didn't last long, nor did anything else I tried! Mind you, like most modern vehicles, the Factory Temperature gauge has been purposefully damped by the factory to keep the punters happy and unaware of what's REALLY going on (your coolant temps WILL be going up and down as the engine load & speed etc. increases/decreases, and as the thermostat opens/closes, but your temp gauge won't show that, cos you might not understand that it's meant to do that!! So it rapidly gets up to and then sits about halfway up the scale... supposedly fooling you into thinking the temp never moves when they are really changing all the time!! ) so that you can't really tell from that if your temp has increased a lot, often until it's too late you really need a more accurate un-damped temperature monitor to show you what's TRULY going on with your temperature!

The Cooling Specialist who used to look after my hard-working Desert & High Country 4WD Tour & Exped Support Trucks advised that even adding the KOTT grilles would be reducing my Spyder's airflow somewhat, and while I could get away with just fitting them because they cause only 'a little' reduction in airflow, the Spyder's Cooling System was really JUST adequate at best (even with WaterWetter! ) so reducing the airflow any further by adding a finer mesh or anything else was quite risky, and he strongly advised against painting the radiators (due to the reduced temperature dispersal that results - there's a reason modern alloy radiators aren't painted ) or adding anything more beyond the KOTT Grilles (due to the previously mentioned reduced airflow)!

Just Sayin'

In my experience the V-twins ran much hotter than my 1330 ...... He has the 1330 .....Mike

[K80Shooter]

Maybe it's hotter where I am in Oz, but adding ANYTHING to the KOTT grilles (even what appears to be exactly the same woven wire mesh as yours K80! ) caused my Spyder to run somewhat hotter all the time and to occasionally shut down due to over-heating - so it didn't last long, nor did anything else I tried! Mind you, like most modern vehicles, the Factory Temperature gauge has been purposefully damped by the factory to keep the punters happy and unaware of what's REALLY going on (your coolant temps WILL be going up and down as the engine load & speed etc. increases/decreases, and as the thermostat opens/closes, but your temp gauge won't show that, cos you might not understand that it's meant to do that!! So it rapidly gets up to and then sits about halfway up the scale... supposedly fooling you into thinking the temp never moves when they are really changing all the time!! ) so that you can't really tell from that if your temp has increased a lot, often until it's too late you really need a more accurate un-damped temperature monitor to show you what's TRULY going on with your temperature!

The Cooling Specialist who used to look after my hard-working Desert & High Country 4WD Tour & Exped Support Trucks advised that even adding the KOTT grilles would be reducing my Spyder's airflow somewhat, and while I could get away with just fitting them because they cause only 'a little' reduction in airflow, the Spyder's Cooling System was really JUST adequate at best (even with WaterWetter! ) so reducing the airflow any further by adding a finer mesh or anything else was quite risky, and he strongly advised against painting the radiators (due to the reduced temperature dispersal that results - there's a reason modern alloy radiators aren't painted ) or adding anything more beyond the KOTT Grilles (due to the previously mentioned reduced airflow)!

Just Sayin'

I'll make sure to keep an eye on the temp gauge. Thanks for the heads up though.

[IdahoMtnSpyder]

Maybe it's hotter where I am in Oz, but adding ANYTHING to the KOTT grilles (even what appears to be exactly the same woven wire mesh as yours K80! ) caused my Spyder to run somewhat hotter all the time and to occasionally shut down due to over-heating - so it didn't last long, nor did anything else I tried! Mind you, like most modern vehicles, the Factory Temperature gauge has been purposefully damped by the factory to keep the punters happy and unaware of what's REALLY going on (your coolant temps WILL be going up and down as the engine load & speed etc. increases/decreases, and as the thermostat opens/closes, but your temp gauge won't show that, cos you might not understand that it's meant to do that!! So it rapidly gets up to and then sits about halfway up the scale... supposedly fooling you into thinking the temp never moves when they are really changing all the time!! ) so that you can't really tell from that if your temp has increased a lot, often until it's too late you really need a more accurate un-damped temperature monitor to show you what's TRULY going on with your temperature!

The Cooling Specialist who used to look after my hard-working Desert & High Country 4WD Tour & Exped Support Trucks advised that even adding the KOTT grilles would be reducing my Spyder's airflow somewhat, and while I could get away with just fitting them because they cause only 'a little' reduction in airflow, the Spyder's Cooling System was really JUST adequate at best (even with WaterWetter! ) so reducing the airflow any further by adding a finer mesh or anything else was quite risky, and he strongly advised against painting the radiators (due to the reduced temperature dispersal that results - there's a reason modern alloy radiators aren't painted ) or adding anything more beyond the KOTT Grilles (due to the previously mentioned reduced airflow)!

Just Sayin'

Interestingly, in contrast the radiators in my Spyder were quite blocked by bugs back in 2016. See discussion and pics here: https://www.spyderlovers.com/forums/...ht=grasshopper. I did not experience any overheating problems at all.

[Peter Aawen]

Interestingly, in contrast the radiators in my Spyder were quite blocked by bugs back in 2016. See discussion and pics here: https://www.spyderlovers.com/forums/...ht=grasshopper. I did not experience any overheating problems at all.

Even if it wasn't quite enough to make your Spyder's cooling system boil &/or the engine overheat, despite what the temperature gauge might've been claiming was going on, it almost certainly WOULD HAVE been running hotter than 'usual' or even 'normal' with your radiators blocked like that - the laws of physics don't just disappear for these things!

However, the damping that is included on almost ALL vehicle temperature gauges these days probably didn't show that temperature increase, exactly as the manufacturers intend! The gauge needle probably just sat around the half way mark or maybe a needle width higher, because that's where the designed damping forces the needle to sit for a fairly wide range of temperatures; but then if you exceeded the usual engine loading &/or reduced the air flow thru the radiators enough, it would've apparently SUDDENLY jumped into the Red as your cooling system over-heated!! And you would've thought that happened with 'little warning', but that would've only been because the gauge & vehicle manufacturers have colluded to stop telling you what your cooling system temperature is ACTUALLY doing in real time; and that is, going up and down as the engine load varies, your speed changes, the air flow thru the radiators & over the engine varies; &/or the cooling systems ability to move & disperse the heat developed changes - as it can and in fact MUST do unless it is massively over specified (and they're not! ) as the engine load, revs, air flow, speed, et al all change as you drive/ride!!

This is a trap for people who don't understand that running your engine harder or blocking the radiator's coolant &/or air flow etc WILL & DOES make your engine run at least a little hotter. Load the engine up enough or block coolant/air flow enough and it WILL over-heat & likely boil the coolant, even if your gauge was only showing half temp a moment ago! This is apparently because vehicle manufacturers have decided that most operators are too dumb to realise that variations in engine load &/or coolant/air flow WILL mean there are changes in the engine's cooling system temp, so the manufacturers have damped the temperature gauge response, often until it's too late to avoid over-heating and potentially damaging things!

If you were relying on the temperature gauge's needle still sitting somewhere around the middle of its range, then you almost certainly weren't aware of how close to over-heating you were probably getting. Mind you, that's fine, you CAN run an engine & its cooling system right up to but not into boiling/over-heating without major issues, and just so long as the engine load doesn't increase any; the cooling air flow doesn't decrease any or get any hotter; that the coolant effectiveness is maintained (some coolants can break down if they run too close to their boiling point for too long); &/or the coolant flow in the cooling system continues at the specified rate and pressure yada yada - but if you've got blocked radiator fins there's WAAAYYY less tolerance of any increases built into the system these days than there used to be - nowadays, in the interests of keeping costs down, there just ain't much tolerance in there to start with!!

Just Sayin'