guru20

How much does the undertray effect temperature? My car seems to be running hot, usually a little over half. The weird thing is, when i go at higher speeds 80+ for more than 5 minutes, the temp rises to about 3/4. Could it be the undertray? I just flushed and changed the coolant, so i dont really know what it is.
Thanks guys

scathcart

Expect a temp drop of 10 degrees Fahrenheit with it on. Well worth it.

dre_2ooo

Check for air bubbles (pockets) in your coolant. Start the engine up (cold) and leave the radiator cap off. Let it run for 5-10 mins and it should "burp" out all the air in the system..... you will have to adding coolant while this is happening as well.

dre_2ooo

the undertray (plastic) actually helps that much? I took mine off when I flush/filled mine a few months ago and never put it back on..... always gets in the way.

scathcart

There was a thread on this this week... a guy had too high hood temps, we told him to put the bellypan back on, and he came back and reported a 10degree drop in temps.
It should be on.

Silkworm

It's helping block the underside of the car, that helps duct air entering from the front grill up and into the radiator. It's a huge help. Just like those two plastic pieces in front of the radiator. Without it, air spills into that area, and isn't smoothly transitioning into the radiator.

PaulC

Wankel7

How bout that foam that was glued to the bottom of the radiatior and the oil cooler. How important was that?

James

Phu5ion

i could believe it, i've left it off since i replaced my lower oil cooler line and the engine does seem to be running quite a bit hotter. I was planning on putting it back on again in Sept. when i have a chance to replace the upper line.

CrazyDude

Hey sean... i'm that guy who put it back on

I think that about 1/3 of the temp drop was due to driving it at night (i went back and checked the next day), but it definitely dropped temps around 3-5 degrees F (not bad for a piece of plastic ).

Btw, I think my fan clutch failed, and that's what was causing it (i'm working on that...)

NZConvertible

It's not hard to understand why the undertray is so important for cooling. Air always takes the path of least resistance, and without the undertray it's much easier for the air to be pushed down under the radiator instead of through it. I wouldn't be surprised if the airflow through the radiator dropped by 30-40% without the undertray.

RX7BEAR

My car is running veyr hot !!!!!! 240 degrees with the air on !!!! I have a new thermostat and cap from mazda . Black magic elec fan. upper and lower trays on . fresh flush of the system with the correct mix of antifreez. only thing I havent changed was rad and the water pump .!!!!! Also I didnt know that there is foam around all that other stuff either ? Were would you get that stuff from ? It runs half way up while driving it goes alittle higher !but turn on the ac and it goes way up !!!!! I do have a mechanical temp gauge so I knwo what the correct readings are on it. What should be normal temps?

dre_2ooo

Normal : 160*F-200*F Depending on ambient temp and elevation.


I usually see about 174*F, but it climbs to 195*F when it's 100*F outside with the A/C on full blast.

NZConvertible

That’s way too hot, in fact that could be doing damage. You may have blocked radiator tubes that the flush didn’t clear, or more likely the water pump impeller has rotted away. Take the water pump off and inspect it.

Scott 89t2

160?? thermostat should be 180 or 185 so it shouldn't be lower then that when warm. 190 - 210 is normal. 240 is WAY to hot.

RX7BEAR

guess Im going for a new pump !!!!! should it be new or reman?