Hello guys,

Yesterday at the ITR EXPO my whole cooling system has decided to take a dump on me. I was over heating as usual after a few laps. But this time; on the cool down lap the Engine Coolant Temp dosen't seem to go down. Pulling in to the pits I noticed few things, my coolant reservoir had over flowed and the cooling fan isn't working.. A few diagnosis confirmed that I had a bad thermo fan switch so I say "heck this is an easy fix", I just jump the connector with a paper clip to keep the fan running.. After that ECT was fine for a few laps then started to climb rapidly. I always turn the heater on to max heat to aid cooling but it wasn't enough. I pulled back to the pits and examined the engine compartment, the fan was still on but when I put my hand over the fan it was blowing cool air!! So I guess the coolant thermostat had gave up too.. When I rev it up to 2K rpm then the radiator air gets hot... I also see a fluctuating ECT gauge so I guess I'm starting to have air pockets in the engine since it puke all the coolant out. Anyway the event turned out great but I just have to limped back to the pits after a few laps after that.

OK here are what I'm thinking of doing..

I might try the evan NPG+ waterless cooling which uses a synthetic liquid instead of water and leave everything stock http://www.evanscooling.com/

Or if I'm going to stay with water:

Switch to a lower temp thermostat and fan thermo switch from Spoon but I don't know how this will affect the OBDII and the wear of the engine.

A higher pressure rated radiator cap.

And a bigger radiator.

I hope you guys could point me to the right direction! Thanks!

Charleston

 

First off, I don't see how switching to a lower temp thermo from Spoon can affect the longevity of the engine. If your engine's not overheating, there shouldn't be any problems with the temp thermo you choose. Secondly, why use a Spoon piece? I mean, a thermostat is a thermostat. Honda thermos should be good enough stock... it's not like you have to build it to handle max flow or something... so why get Spoon? I just don't understand... is it lightweight? I'm curious.

Anyway, if your reservoir overflowed I'd think that your coolant was getting hot enough to boil. Luckily it didn't blow a hose or anything. Try using some Redline Water Wetter or upgrading to a larger radiator. However, I'd recommend not using NPG+ synthetic liquids... most dragstrips won't allow you to run with coolant in your tanks. You have to drain the system first and fill it with water. So if you ever planned on going drag racing, you'd have to swap back to your water-cooled system, then back to the NPG+ system after the dragstrip. PITA if you ask me.

Anyway, I hope that helped... let us know if you solve the problem...

 

Hello, thank you for your reply..
An engine running below optimum temperature will tend to wear out the cylinders typically in the lower part since they are not expanding as much as the ones closer to the head which is hotter. Second, an engine running cool will not heat the engine oil enough that blowby acids and other nastly chemicals won't vapor off and they tend sludge up.. Third if the engine is cool it PCM won't switch to close loop because it thinks the engine isn't warm up yet.

The spoon and mugen thermostat opens at 160°F compared to the stock one which is 180°F.. A slightly hotter engine is good for cleaner emission many smog guys say... I don't know if 160°F is the optimum temperature for power and wear.. what do you think?? Thanks again..

Charleston

 

I switched to Mobil 1 and my max temp droped about 10-15%.

just some thoughts: an ITR stock all alumn. or a fluidyne radiator; and a better fan; new water pump.

When was the last time the system was flushed?

 

That's interesting.. I've been running with Mobil1 synthetic since 1500miles... so I didn't get to compare before and after engine coolant temp.. by they way what device did you use to read the temperature?

Yeah it seems that everyone's advise is to get a bigger radiator.. so I'll think i'll go for it..

I change my coolant reguarly about every 6months or 20K miles..

Thanks matt!

Charleston

 

I don't know if I agree with you on that assessment about the top being hotter. For starters, the entire block is cooled by circulating coolant and oil, with the express purpose of delocalizing and decentralizing heat. Coolant flows up and down the sides of the pistons, thereby creating a uniform temperature. Besides, a 20 degree difference is hardly going to cause that much swelling of metal! Especially considering that the heads have the cold outside air flowing in through them as well as fuel injected into them (fuel atomization causes cooling). As a final point, note that metal conducts heat rather well... stick a cold spoon into a boiling pot of water, and you'll quickly notice that the handle grows too warm for comfort. The same would be true of your cylinder bores... the heat would naturally tend to redistribute itself evenly.

Besides, if this was a problem as you say, then it would occur at ALL temperature levels, nevermind if the engine is running 20 degrees cooler or not. Hence, it would be a factory problem.

Now, if the thermostat's a Spoon part, I'd be inclined to believe that it's not going to make the engine run so cool as to disable your VTEC function. Spoon would have to be silly to market a part like that .

If you're worried about not running hot enough and accumulating crap, then periodically run a quarter of a bottle of methyl hydrate through your engine. That has the effect of temporarily raising the engine's operating temperature roughly 40 or 50 degrees, thereby burning off excess sludge. It's a common trick used to pass emissions on older cars.

I hope all that made sense... I'm not an expert but that's just how I see it .