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Green Bullet ST205 Re-Born - 6G Celicas Forums

Topic #77385 1008 posts Started by bsamps4
Guys I'm posting this video for two reasons.

Reason 1: For your enjoyment (I enjoyed it too wink.gif)
Reason 2: Watch the temp gauge when I boost. I don't freaking get it??? The temperature actually goes down both on my aftermarket coolant temp sensor, and the factory temp sensor. Only happens when I'm cutting through the air really fast.

No I'm not overheating, Yes I did a compression check (all cylinders read 140psi), I burped the coolant, I checked the coolant for air bubbles from a possible failed head gasket. I'm stumped. I currently have the fans running continuously, but the car will hold around 183 degrees under normal driving, 192 at stop lights, and drops significantly when I'm giving it the beans. I have a Koyo rad and a ATS 180 degree thermostat.

Here's the link to the vid...

https://www.youtube.com/watch?v=QfMMd0k5EpM...feature=mh_lolz

This post has been edited by bsamps4: Mar 26, 2012 - 9:29 PM
I have a theory.

you said you have a koyo radiator. Which means it's capable of quite a bit of heat exchange and holds a larger amount of coolant compared to the stock radiator. While driving around normally your water pump only flows a relatively low amount of coolant, and so that coolant therefore has a longer time to lose heat as it passes through the radiator and gets chilled to a very low temp. During normal driving a relatively small flowrate of this well-cooled coolant exits the radiator and passes the temp sensor. That's why you have normal temp readings during regular driving.

But then when you floor it, all of a sudden the water pump flows ALOT more coolant and flushes the really chilled coolant out of the radiator very quickly. So your temp sensor sees nothing but really cool antifreeze until the extra heat that comes from running the engine hard heat soaks the system.

meaning nothing is broken, you just have a cooling system that has more capacity than you need at the moment. But that is a good thing, since you can accommodate future mods and wont have to worry if theres a 90+ degree track day


This post has been edited by enderswift: Mar 26, 2012 - 9:24 PM
I like your theory! Glad you didn't jump immediately to "broken"!
nice wording of your theory

but sadly, the reason for that is that his thermostat is stuck open.


Replace your thermostat.

This post has been edited by Culpable04: Mar 26, 2012 - 9:25 PM
I thought it was already replaced
It's a brand new thermostat. ATS 180 degree thermostat. I installed it with the little bead thingy at the bottom.

This post has been edited by bsamps4: Mar 26, 2012 - 9:31 PM
culpable is probably right. A good way to check is to rev the motor while parked to see if the temps drop. That should verify

This post has been edited by enderswift: Mar 26, 2012 - 9:39 PM
>
QUOTE (bsamps4 @ Mar 26, 2012 - 10:30 PM) *
>It's a brand new thermostat. ATS 180 degree thermostat. I installed it with the little bead thingy at the bottom.



re-check it, because the only way an excess of cold coolant would make its way into the engine bringing the temperature below optimal operating values is if the thermostat is stuck open. and yes, it's something you need to address as pushing your engine while below operating temperatures will cause excessive wear.
I'll call toyota in the morning and buy the stock thermostat. Cross referencing the part number here looks like it is available in the U.S. market. Weird thing is it works for these vehicles: 4runner, landcruiser, and sequoia. Part number is 90916‑03100.

I will crank the boost down in the morning and drive it like a grandma till I replace it.

It's never gone below 170 degrees. So I really hope I haven't "hurt" anything.

This post has been edited by bsamps4: Mar 26, 2012 - 9:38 PM
does the needle go all the way down while cruising ?
The car does run kinda rich at idle because of all of this. Better than lean!
No...the needle stays between 180 and 185 while cruising, but it stays closer to the 180 side on the highway.
the factory needle.

does it go all the way down ?
Are you referring to under boost or normal driving. It tends to stay steady during normal driving, but decreases during heavy boost. You can see it in the vid.

No it's never gone all the way down. Just a little bit.

This post has been edited by bsamps4: Mar 26, 2012 - 9:52 PM
It seems toyota engines are just very sensitive to thermostats. Last winter my car started to lose temp whenever I drove above 10 mph and I assumed that the thermostat wasn't closing all the way. I went to toyota, purchased a new one, and proceeded to swap it out. For whatever reason I ended up boiling a pot of water and dumped the old and new one in. They both opened all the way, and then closed completely when cool. I was stumped and put the old one back in, but the problem persisted. Eventually I swapped it out for the new one and the problem went away. So it might not be that yours is stuck, but rather that its not responding fast enough; which when coupled with a better cooling system, could be leading to your problem. So I agree that you should try another thermostat.

This post has been edited by enderswift: Mar 26, 2012 - 10:12 PM
I def will. I just hope I haven't damaged my virgin motor.
I doubt it. If you drove those 400 miles the way you did in the video then there's really nothing to worry about. Besides these motors are actually pretty resilent, and the gauge only dropped slightly.

Have you guys ever seen people rev the piss out of their cars in the winter to warm it up faster? Now something like that would destroy a new motor.

This post has been edited by enderswift: Mar 26, 2012 - 10:21 PM
Haha i hear ya. I was suprised to see the compression so perfect so soon. I love the way it drives. I'm just ready to have all the kinks worked out, and have the break-in behind me. I'm ready to hunt some mustangs.

This may seem silly to you guys, but i'm gonna lay it down anyways. I built the car to DESTROY s*&t american cars that only make 50 hp per liter, and get terrible mileage. Then again I have a huge respect for the way Ford turned things around, and actually now creates quality mustangs. I just feel like they were so embraced by their early fan base that they let quality slip, and people STILL bought those things. I don't hope to crush a 2012 because I know I'd be destroyed, but I'm ready for any 2010 or under!!!
You guys fixed the problem. Twas’ the thermostat!
>
QUOTE (bsamps4 @ Mar 26, 2012 - 9:57 PM) *
>Guys I'm posting this video for two reasons.

Reason 1: For your enjoyment (I enjoyed it too wink.gif)
Reason 2: Watch the temp gauge when I boost. I don't freaking get it??? The temperature actually goes down both on my aftermarket coolant temp sensor, and the factory temp sensor. Only happens when I'm cutting through the air really fast.

No I'm not overheating, Yes I did a compression check (all cylinders read 140psi), I burped the coolant, I checked the coolant for air bubbles from a possible failed head gasket. I'm stumped. I currently have the fans running continuously, but the car will hold around 183 degrees under normal driving, 192 at stop lights, and drops significantly when I'm giving it the beans. I have a Koyo rad and a ATS 180 degree thermostat.

Here's the link to the vid...

https://www.youtube.com/watch?v=QfMMd0k5EpM...feature=mh_lolz


The t-stat as you found was defiantly the culprit (glad you got that sorted), but the fact that you do not have the fans relayed to a temp switch, will also hyper cool the fluid in the rad, and when the fluid moves it will drop like what you saw.. i would get the fans hooked up and relayed to a temp switch asap.. also will keep the fans from putting too much of a strain on you electrical system. (and it will over time)

"The buy my stuff, for help make great finish project of celica fund!"
I have the switch on order. Just a temp solution for the moment.
>
QUOTE (bsamps4 @ Mar 29, 2012 - 2:33 PM) *
>I have the switch on order. Just a temp solution for the moment.

cool.. wink.gif that should take care of any "non-normal" operation of your cooling smile.gif great progress BTW!!! freeking awesome.

"The buy my stuff, for help make great finish project of celica fund!"
Fingers crossed for 300 horsepower! The motor is built to handle 500, but I wanted to over build to be on the safe side. I want it as reliable as possible since it's my DD. It's killing me to not turn the boost control knob. I wanna crank it to 17 already!
glad to hear you found the problem. how many miles does the motor have on it as of now?

st205 powered ss3 coupe
totally agree, overbuild to handle aprox 25% more than what you plan to run.. gets your reliability back.. but if your tune is crap, it wont matter if you built it to handle 1k hp.. it will still blow. only a mater of time.. i am SOOOOO on your level of break it in right too.. i am about to drop my project back into the car, and it will need to be broken in right as well, but i will be going for motoman's basis for breaking in motors.. keen on getting the rings to seal correctly.. everything else is just tolerances..

stock turbo? if so how many Lbs are you expecting push to be able to get 300 whp?

"The buy my stuff, for help make great finish project of celica fund!"
I'm doing the motorman approach as well. I drive it like I stole it, but on low boost. My compression test already revealed a perfect ring seat. It was 140 across all 4 cylinders. Hoping to see what I get with 17 Psi.
Then again my thermostat issue may have thrown a bone in my plan. We shall see.
Another bone headed question for you guys. I live in North Carolina and it gets hot enough that A/C is a must. I kept the a/c on the 3sgte, but when I hit the button I don't feel or hear the magnetic clutch on the a/c click over. Is there something I need to do with the wiring to get the a/c working on this thing?

Also curious about my boost controller install in reference to the tvsv ( My boost controller works fine btw), but i'm trying to track down any possible vacuum leaks. I still have the line connected to the top port of the tvsv, and a cap on the bottom. Is this correct? The car also still has the anti-lag set up on it, but I capped the nipples on it.