Hey guys, lemme see if i can get any ideas from you, maybe someone has had a similar situation. I have a Turbo II swapped S5 and it has always ran great, i have had no shroud on the stock clutch fan with a fluidyne radiator and never had any cooling problems. I recently put an Apexi GT Exhaust on and noticed once when driving around for a while it got warmer then usual, not like overheating warm, but about 3/4 up the gauge. Today i installed a Fiero E-fan, thinking i should have no cooling problems at all. As i was driving it around tonight i noticed that it runs great temperature at idle, but with any load on the motor whatsoever, even just cruising at like 3k rpm it creeps up to about 3/4 way up the gauge, but as soon as i come to a stop or put it in neutral, it immediately drops down to halfway with no hesitation.


Can anyone make any sense of this? Any ideas on where to start looking? I have no coolant leaks and my coolant sensor doesnt buzz at all. Any help is appreciated

 

just an idea wouldnt hurt to check, see if your thermostat is opening.

put water in a coffe can and put the thermostat in the boiling water and see if it moves

my buddys shitty seabring has a stuck thermostat and his car rises about a 1/4 inch BELOW the H line

 

more details please? i boil the water, then where do i put it? into the radiator? or pour straight into the thermostat?

 

3/4 up the gauge IS overheating.

Does it blow any white smoke?

When did you last replace the thermostat?

replace it......if its been a while.




john ny

edit

 

Take the thermostat out altogether and put it in boiling water in a container outside of the car and watch the t-stat to see if it moves.

 

Well, im going to get a thermostat locally for 18 dollars and give it a shot this weekend, ill see if theres any change i'll let you know thanks guys

 

buy a brand new one from mazda

 

do you have the stock Belly pan(skid plate) on the car?.It does help to have a shroud of some sort on the Rad and a belly pan to make sure the air is Going towards the engine and cooling it down.

 

Ok guys i put a new thermostat in and put my underpan back on and its still getting hot, any other ideas?
Could it be that my FMIC simply isnt allowing good airflow to the radiator?

if so what is the solution to this?

 

No, you are in Dallas. Get one from Rotary Performance. Support the community.

 

I can tell you that if the gauge on your S5 is at 3/4, the temp is approaching 250* at the at the waterpump housing.

Clogged radiator? Check the face for landscape debris such as grass clippings, cottonwood 'cotton' etc.

Slipping water pump pulley -have you recently removed the airpump? Maybe you solved the cooling problem (no shroud) and added another different one?

How about the waterpump-have you inspected the impeller of the pump? It can become eroded by bubbles and cavitation at higher rpms.


Also, how are you controlling the Efan? What location are you sensing and at what temperature?

 

is the oil cooler in good shape without any blockage?

 

My efan is wired directly into the main engine fuse so it is constantly running, i know this is excess load on my alternator but i'm going to be upgrading the alternator soon

the airpump was removed when the turbo II swap was done as the intercooler piping required it to be removed, I'm going to check the waterpump pulley when i get home

any other ideas?

 

Where did you get the thermostat?

What coolant mix are you running?

Can you see the coolant rushing by the open radiator cap when you are at idle?

 

Thermostat from Rotary Performance. 50/50 PEAK brand coolant mix from auto zone.

I don't really see the coolant rushing, but its in there lol

 

If your air pump is removed you should be running a double alternator pulley or a yoohoo belt to prevent slipping. Could be causing your problems.

 

I have a idea...

Does your water pump leak? They have a weep hole that will start to release water once the water pump is starting to go out. It may not be enough to leak on the ground but will be all over the front cover.

Are any of the fins in the Fluidyne bent? Any patched spots?

Is the exhaust a full turbo back or just a catback? Try some exhaust wrap, see if it helps.


If your getting to 250+F driving around, those coolant seals are gonna be gone in no time flat.

 

0.0 wait is 3/4 overheating on a s4 too?

 

Getting there. But won't be as hot as 3//4 on an S5.

Its hard to correlate though. I've seen a bit of variance between cars....on my S4 1/2 is around 90C on the EMS. Never seen 3/4 (yet )

 

shittttt haha my car runs around 3/4 on the highway now that i put in my fmic hopefully new less leaky oil cooler lines and new radiator hoses i put in help that. ok im done thread jacking now

 

Once the thermostat is open- 190* and up, you should see the coolant rushing by the cap. Rev the engine and it should rush noticeably faster. If it doesn't, there is something restricting the coolant flow. Could be clogged radiator or collapsed hose. Check the lower hose as it can collapse and restrict the flow back to the waterpump.



The S4 gauge reads linearly, just like an aftermarket gauge.

The S5 does not read linearly. The changed the S5 and the S6 to a stabilized gauge.

Who knows why, but Mazda thought it better if the needle stayed in the middle of the gauge. My OEM S5 gauge hits the middle at about 190*. It does not move one bit even if my actual temp (measured at the waterpump on a VDO gauge) goes to 225-235*. It moves to 3/4 when my VDO reads +250*.

 

Ok sorry dumb bit should The efan be blowing air onto the radiator or sucking it off?

 

should be sucking lol thats what she said

 

What kind of intercooler core are you using? Give us some pics of where and how it is mounted.

I had this cause my car to run warm as well.

 

I drove it around a bit today so i hope this isnt premature but im 90% sure the problem has been solved simply by reversing the direction of the efan, i had it pushing, now its pulling and cooling looks to be pretty much perfect