Seems that I'm still having the same issue as before? I am running a new koyo n flow, new oem thermostat, 300zx TT rad caps -16#, and the Taurus fan on high. I am getting my temps from behind the water pump via microtech. Am I missing something? Microtech is throwing the water temp code. I am running a massive ic with no underbelly. Any help is appreciated, thanks!

 

did you completely bleed the air out of the cooling system?

 

Your hardware seems up to the task, so you'll have to look elsewhere.
The comment " I am running a massive ic with no underbelly" is troubling.
A big obstruction and no ducting would lead to the radiator starving for air.

 

Trying to find an underbelly is like looking for a unicorn around here. I am wondering if venting the hood would help the situation? I could cut underneath the hood where there is no bracing by the rad? Should I just go back to the fan clutch? I have not used water wetter yet, and the fan is on always! It's Florida. Thanks

 

The one thing, I am running a jaz overflow tank with no water, in it? Would that be my culprit of air?

 

Why worry about extracting air that doesn't seem to exist?
You need more air coming in before a vented hood becomes necessary.

How do you go back to the thermoclutch fan...I don't think the shroud will fit with the new Koyo.

You seem to have the right parts but they're set up wrong.
There's no way a Taurus fan should be constantly running on HIGH, even in Hell (or Florida).

Is the Jaz set up as just a catch can or as a recovery tank?

Let's see some pics of this whole setup.

 

The jaz is a recovery with an inlet at the bottom and outlet at top

 

OK, then why is it running dry?

 

 

Only difference right now is the koyo n flow. Should I fill the jaz tank? It only has nipples for the hoses.

 

 

 

Are you running the car without the nose?
If so I would seriously invest some time into finding an undertray and putting the nose on.
I posted a thread in the parts wanted section and had an undertray brought and sent to me in about 6-8 days.

Justin

 

The bumper is on, this was just mounting the ic.

 

Your Jaz Overflow tank has its inlet at the bottom and the outlet at the top? If it operates as I am thinking it does, it needs something (air filter, curved tubing pointing down, etc) to prevent debris from entering at the top and clogging the bottom inlet. Otherwise, it sounds like a smartly designed piece of hardware as it is assisted by gravity upon coolant contraction rather than the stock arrangement that fights gravity on cooldown (and could suck in air easier).

Going to be a dumb question, but are you sure there are no gaps around the radiator? If air flows around it, it isn't being forced to go through the radiator. Also, what thermoswitch(es) are you using, specifically their on/off temperatures? You may already know this, but the thermoswitch needs to complete the circuit at a higher temperature than the thermostat opens at. Depending on how your fan circuit is designed, you may or may not need a 2-pin thermoswitch. If that is the case, be sure to check out the Mitsubishi 3000GT's fan circuits. They use 2-pin thermoswitches that share our M16x1.5 thread pitch and the activation temperature is very similar to the FD's setup. The actual switches are threaded into the bottom of the 3000GT's radiator on the passenger side. See my build thread https://www.rx7club.com/build-thread...tormas-888195/ for more information.

An undertray wouldn't be TOO difficult to fabricate by hand out of sheet metal, depending on the front bumper you are using. On the stock S4 one, there are several holes on the bottom edge used to mount the S4 Aero Kit. Run some M6x1.0 bolts down from the top to see where they line up in relation to the engine cradle crossmember. Engine cradle has three M6x1.0 threaded holes in it for this reason.

On my 20B S4, the middle and passenger side holes had enough room to thread a bolt in from the top without dismantling the steering rack. Driver's side one had to be put through the bottom.

Get a piece of cardboard and a ball pein hammer. Using your bolts-turned-studs on the front bumper, hold the cardboard up and tap where the bolts go through. You'll get a pattern with correct spacing. Repeat for the engine cradle part and transfer the holes onto metal. Now trim to fit perfectly and add reinforcement ribs where appropriate. I'd suggest at least two running front to back and once side-to-side.

 

how much pressure is your cooling system building? does the heater work? thermostat in place and has been checked?

 

The undertray was the final solution to many rx7s overheating isssues. +1 for fabbing up a new one.

 

New oem thermostat and 16 psi caps. No heater or ac, I'm going to burp it again and put some water in the catch can

 

Sure, go ahead and make an undertray, it can't hurt.

I'm betting that the new tray will show that the real problem is the intercooler.
You are not getting enough air to the radiator.

Have you considered a different configuration for the two heat exchangers?

 

Honestly, I'm considering selling the headache.

 

Would a pusher fan help?

 

i have a nissan quest fan on a ebay rad. its runs soo cold now sometimes. with the fan on speed 2 . i have more water then coolant and used some water wetter aditive. factory thermostat and cap . and i also have a front mount. and factory underbelly on. i had same problem before .

 

short answer is no. a pusher would just add more resistance for the puller to draw air through.

 

why dont you listen to the advise on the forum and get an undertray?

what i have logged on my haltech, on the same day.

without undertray on a stock car
idle temp 185*f. cruising was 206* even creeped to 210*.

WITH undertray on

idle temp 185*. cruising was 192*. solid as a rock. after a pull, would creep to 200 maybe.


whats soo hard to understand? when driving, air slams into the radiator, and goes underneath the car. to prevent this, mazda put an undertray to force air through the radiator.

JUST EFFING DO IT!


also, you will over heat cus your front mount is stupid huge for no reason and blocking all that awesome air.

 

I am searching for an under tray at this moment. Thanks guys!