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question about coolant and thermostat.

2028 Views 37 Replies 9 Participants Last post by  squintypanda
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I am about to clean out my radiator and coolant myself tomorrow, and need some advice on Coolant/Distill water mixture? what % should I mix them in?

also I heard something about "lower thermostat" that allows the coolant to circulate in the engine at a lower temperature, anyone knows anything about that?

thanx!
Jonas
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I did this not too long ago. I bought a gallon of the Toyota Red coolant, $15. It took a gallon of distilled water and the entire gallon of the Toyota Red coolant to refill the system. I just did a 50/50 mix. You can do a 70/30 of coolan/water mix if you want, but I think 50/50 is adequate. Use a seperate gallon jug to premix the coolant and water, then pour it in. They make a special funnel that snaps into your radiator cap location to refill the system, it allows you to fill and let air out of the system at the same time.
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hey thanx for the info!

does Toyota sell that special funnel you talked about?

do you know where the engine drain plugs are located?
You can buy the funnel at an auto parts store in your area I am sure. The entire funnel looks like a normal funnel, but at the bottom is an attachment that is verbatim to a radiator cap. I did it at my old work on the lift to make it easier on myself and they had them there.

As far as the engine drain plug for the coolant, I didn't need to use it. I just drained from the radiator plug. I checked the lower radiator hose as well after I was done draining and nothing came out of it.

I'm pretty sure all of it comes out through the radiator plug, just make sure your car isn't tilted back or something when draining.
G
so with that funnel, you didnt need to bleed the system?

thanx for your help
I just flushed my cooling system and installed the TRD thermostat(160 degree). It basiclly starts the coolant throught the radiator sooner so that it keeps it cooler. I have a temp gauge installed and here is the before and after .

Conditions:
After 25 minutes+plus warm up(stop go DC traffic).
air temp~83F

180 thermastat-195
TRD 160 thermastat-172

The only thing different from stock cooling system (other than the therma.) is that I have a fluidyne radiator. 60/40 mixture.

-TY
Zerosoul said:
so with that funnel, you didnt need to bleed the system?

thanx for your help
Nope, the funnel lets all of the air escape.
Actually, you'll need to drain the fluid from two points, the first is the main one under the radiator, and the second is close to where the downpipe attaches to, it drains the block. Also, I used Toyota red as well, went with a 60/40 mix of water/coolant with some Redline water wetter and installed a TRD thermostat and TRD radiator cap.

Alan
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I just drained from the radiator....also jacked the car up from the back to drain as much coolant from engine as possible.

weird thing is I only used 3/4 of the whole gallon of Toyota coolant. I mixed 50/50 with distill water and I only used 3/4 of water also....guess its becuase I didnt drain "all" the coolant from the block.

I replacd the thermostat also..stock one. it wasnt very fun, was under the car and when the hose came lose coolant got on my face....I think a bit went into my month, should I be worried?
Zerosoul said:
I just drained from the radiator....also jacked the car up from the back to drain as much coolant from engine as possible.

weird thing is I only used 3/4 of the whole gallon of Toyota coolant. I mixed 50/50 with distill water and I only used 3/4 of water also....guess its becuase I didnt drain "all" the coolant from the block.

I replacd the thermostat also..stock one. it wasnt very fun, was under the car and when the hose came lose coolant got on my face....I think a bit went into my month, should I be worried?
No-I have sampled all fluids from a car at one time or another. Coolant has a nice sweet taste to it. Burnt auto trans fluid is the worse. I do have this stange tick and sometimes go into uncontrollable convolsions though....J/K as long as you didn't drink much of it you'll be alright...
How much was the TRD thermostat? I need to do that myself.
G
At what point is the car running too cool? Lance at Toyomoto seems to like his cars running hotter than cooler...
Jon, its not going to help you. It will only slightly delay your car overheating.

Cars are designed with a specific temp thermostat in mind, and unless some logs better timing advaance and less knock with a cooler thermostat, I'll stick with the stock one. Colder thermostat means more energy absorbed by the cooling system which means less heat goes into pushing the piston down.
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Grant,

thanx for the info, seems like you have good knowledge on cars! nice.

:bthumb:

BTW, last night during a high speed run my EGT reached 730C again....AGAIN! I dont understand, now I am beginning to wonder if my gague measures different from Greddy/HKS gauges. (I use Omori electrical EGT)
I have replaced fuel pump, FPR, fule flter, cleaned injectors, replaced coolant, thermostat so far...it did help me lower my EGT considerably, but still not as low as I wanted to be. (BTW my fuel pressure is right where it suppose to be at idle and at full boost)
I think I am running really rich too cuz during high sped run my friends behind me sees me shooting out fire couple of times.
I have my HKS AFR set to self-learning mode so its not effecting stock AF curve I think. any other ideas on what to check?
Set the AFR to zero till you can dyno tune to low 11's for A/F ratio. Then see what the EGTs do.

What the hell is self-learn mode? It doesn't have any input to give it good information (stock o2's are useless, only a wideband can be used for this purpose), so there's nothing it can learn from.

Andi
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Andi,

HKS states that under Self learning mode it will help stablize RPM at idle only, in case of sudden drop of rpm for some reason (ex.BOV). My EGT was high before I installed the HKS AFR and I have hooked it back to stock couple of times, no differnce in EGT.
Zerosoul said:
Andi,

HKS states that under Self learning mode it will help stablize RPM at idle only, in case of sudden drop of rpm for some reason (ex.BOV). My EGT was high before I installed the HKS AFR and I have hooked it back to stock couple of times, no differnce in EGT.
Oh ok...... :)

Andi
TRD Thermostat?

How much for a TRD Thermostat vs a stock one?
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wy dont you email Jeff W at Jay MArks Toyota. they sell TRD parts cheap.
FYI, I bought stock thermostat for $14 at local Toyota parts. so it shouldnt be too much different with TRD ones after discount.

Jonas
I paid ~$70 for the TRD thermastat. Got it through Jay Marks(Jeff).

I would rather have my car run on the cooler side to prevent detonation(hot spots in the cylinders), prevent cylinder head warp and head gasket failure, not spit coolant all over the track, and hopefully make more HP(every 11 degrees cooler you pick up 1% more HP) and I know there is a TEMP range that the engine needs to operate in. Just remeber you can overshoot that range also.

-TY
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