gz91rx7

Ok my add coolant buzzer has been going off recently and today when I was out driving it came on again, I pulled over and the overflow tank was boiling and when I went back around to look at my temp gauge it was starting to climb. I shut the car off and went to feel the radiator hoses. the top one was very warm and the bottom was cold.

Please help!

Josh

DC350

sounds like a clogg in the rad...or a bad thermostat.

yearrgh

Possibly a bad rad cap, also check your filler neck. If the inside where the seal of the rad cap pushes down looks chewed on, it needs to be replaced also.

gz91rx7

anyway to check for the thermostat?

gz91rx7

if it was the cap, would that cause my coolant to boil?

yearrgh

boil it in a pot of water with a thermostat, it should open at 110 deg. if my memory is correct.

gz91rx7

How hard is it to get the thermostat out? if there a good site with a write up?

yearrgh

It would prevent the coolant system from sealing properly. That would cause it to spit coolant into the overflow, causing bubbling and eventually overheating.

yearrgh

very easy to take out the thermostat. follow the upper radiator hose to where it goes to the plastic thing. That's the thermostat housing. It has 3 10mm bolts on it. Pull that off and the thermostat is right there. Just put a thin coat of rtv sealant on it when you put it back on and be careful to only torque the bolts to 15 f/lbs of force

gz91rx7

does any of this sound like a failed coolant seal?

eViLRotor

iTrader: (2)

IF you've elminated all other possibilities...yes.
My friend has the same overflow problem on his FD this summer...coolant seals where shot

gz91rx7

the engine only has 13k on it so I am really hoping that it isnt the seal. I get some white smoke on start-up but withing a few seconds its all gone.

Thanks to everyone I am just trying to pinpoint this problem

SureShot

Overheating – check list
1) Replace the thermostat. Make sure it fits. The spring loaded disc under the stat valve must close the bypass port, or guess what?
2) Replace the radiator cap. Low pressure = steam bubbles = spit out coolant.
3) Look for leaks. (same symptoms as #2) Some can be very hard to find. You may have to pressure test it. A common failure spot is the 3/8” coolant line that runs from the top of the rear housing (under the intake runners) to the throttle body, to the BAC, to the water pump. Another one is the heater hose under the oil filter.
4) The fan clutch will slowly start slipping as it ages. The fan should pull really hard up to about 4k when the motor is hot. It should maintain about 4k as the motor revs higher. Sometimes you can get more life from it by bending outward the bi-metal strip on the front of the fan clutch. The cut-in for the series 4 fan clutch is gradual – it pulls some even when cold. The series 5 fan clutch is more on/off.

gz91rx7

so with these symptoms does it sound like a failed coolant seal? That is my main concern

HeffBoost

I would think the cold hose/hot hose would indicate a thermostat failure. Do the easy stuff first and see what happens. Cheers

Aaron Cake

iTrader: (1)

http://www.aaroncake.net/rx-7/cooling.htm

gz91rx7

OK here it is, I flushed the rad and replaced the thermostat. the buzzer went off once. I got home and the overflow tank was full of steam. The upper hose was still hot and the lower one was actually kinda warm. I keep filling it with coolant...............I really hope that it isnt the seal!!!

gz91rx7

here is one bad thing that I noticed, the overflow tank kinda smelled like gas. if I am not mistaken this means my coolant seal failed!

gz91rx7

bump

wwilliam54

replace the rad cap

most common source of overheating

gz91rx7

OMG! I cant believe that a rad cap would cause so much headache in my life!

gz91rx7

ok, so here is the latest. I replaced the cap today and no such luck.

The buzzer comes on every once and a while. The temp gauge will go up for like 10-15 seconds and then will fall back to normal.

After I drove home from work (6 miles) I stopped the car and went inside. I went to pull it in and it didnt want to start. Then when it did......................a huge cloud of smoke from the exhaust!

Also after it was idling at normal temp the overflow was boiling still and was getting full, like almost to the top of the tank. Then after I shut it off all of the coolant was gone out of the tank. ?????? Probably in the engine.

Dvst8

iTrader: (6)

go to your local shop and get it flushed with a new thermostat. Then you will know for sure and save you the headache.

GOLD7

I don't mean to hijack you your thread gz91rx7 but i have the same problem with coolant bubbling in the overflow tank. It only happens every couple days but it started the day I had the upper line from the oil cooler replaced. The overflow tank bubbled for the first time when I drove home from having the oil cooler line replaced. Should I be looking for the same stuff gz91rx7 is looking for (rad. cap, hoses, clutch fan, etc...), or does it have something to do with the oil cooler line?
Thanks for any help.

Craig

marcus219

what does it do when you crank it with the cap off? gizer?