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Old 10-13-2011 | 03:15 PM
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Overheating

I was wondering if someone could help me sort out this problem, Tuesday I noticed my Autometer Water Temp gauge reading between 210-215 degrees on a trip to town, anyways it seems to overheat really quick, if I drive a mile it will be around 200 degrees. The radiator light has not came on yet, but just going by my autometer gauge I am overheating, so I took it to a mechanic and he told me a possible blown head gasket. However he couldnt fix it because it's a "rotary". It does cool down on the HWY but usually just drops from 210-215 down to 200ish. I raised my hood after I got back from picking it up and I could smell a little something burning, I got looking around and found some liquid sprayed everywhere. Also you can hear like a clicking sound from what sounds like one of the pulleys with the car on. Im hoping this is a water pump problem, any suggestions guys ? Only 27k on this 2004!
Attached Thumbnails Overheating-img01693-20111013-1428.jpg   Overheating-img01696-20111013-1428.jpg   Overheating-img01694-20111013-1428.jpg  
Old 10-13-2011 | 03:20 PM
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i would suggest pulling the airbox and inspecting the fans. it is a known problem for the rubber airbox grommets to fall into the fans and lock them up, resulting in burned out fan motors.

spin the fans by hand to see if there is any resistance and check the fan relays/fuses(disconnect the battery first).

i can't really tell what the fluid is from, check all the fluid levels to see if any levels are dropping. it could be from the A/C compressor pop off valve, which will bypass some pressure if the high pressure side overpressurizes due to overly hot temps and an overcharged system.

Last edited by Karack; 10-13-2011 at 03:23 PM.
Old 10-13-2011 | 03:29 PM
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Yes, you are slightly overheating. The overflow tube from the coolant bottle hands right above the fan and steering components.

What are ambient temps in GA right now?

200F is much higher than it should be for low load highway cruising. 210-215 isn't actually a "problem", but it's higher than we like to be. If highway speeds and ambient of under 100F isn't cooling you down to around 180-190F, then you likely have an airflow problem, not fan problem.

Your issues are likely one of the following:
A) Too many smashed vanes on the A/C condenser in front of the radiator, restricting air flow to the radiator itself
B) damaged or missing foam which "seals" the sides of the radiator, forcing air to pass through it instead of around it (removing those makes a noticeable difference in coolant temps)
C) damaged or missing splash pan that allows air to just empty under the car instead of going through the radiator first
D) incorrect or contaminated coolant

Coolant and oil temps are related, and if one is climbing, the other will be as well, so also check for any blockage or damage to your oil coolers that might be preventing the oil from doing it's share of the cooling.

It is likely NOT:
A) your fans (if it was fans, you would see more of a drop at highway speeds)
B) your water pump (usually almost instant 230F+ temps, fluid pouring everywhere)
C) your thermostat (same as above)

During the summer (90F+), stock 8s without cooling improvements usually run 200-210F in the city, but should still drop to 180-190 on the highway.

Last edited by RIWWP; 10-13-2011 at 03:33 PM.
Old 10-13-2011 | 03:41 PM
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OE coolant temp for the low speed fan setting is 207 degF and 214 degF for the high speed fan setting
Old 10-13-2011 | 03:45 PM
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Its 83 right now, when I ran to town it was around 10am so temps would have been low-mid 70s.
Old 10-13-2011 | 03:48 PM
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if the a/c is on when you are hearing the click sound, it's probably the compressor cycling due to a low charge which is why i mentioned it could be oil from the a/c system.

if the fans are not working then the a/c system overheats/overpressurizes rapidly. but meh, the fans aren't utilized all that much but they should be on with the a/c running, a simpler test would be to feel if there is air coming across the front of the motor with the a/c engaged.
Old 10-13-2011 | 03:49 PM
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I'd say that it's airflow. If coolant wasn't moving around, you would be spiking far higher, and if it was something about pushing the air, you would be fine (~180-190F) at highway and probably at where you are or higher in the city, where you need the fans to push the air. Not much change for both environments in those ambient temps tells me that whatever air is moving into the nose of your 8 isn't efficiently getting to the radiator to shed heat.
Old 10-13-2011 | 03:52 PM
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but why ignore the fans completely? it's not difficult to rule them out and various climates give different results with the fans off, granted those temps are not super sky high but they will rise more rapidly if the a/c is running and not drop as much at freeway speeds.

i have a hard time envisioning that the condenser core got plugged up with debris rapidly, unless a plastic bag got sucked into the front grille opening.

Last edited by Karack; 10-13-2011 at 03:54 PM.
Old 10-13-2011 | 03:52 PM
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I did notice what looks like rust in the coolant, maybe a flush would solve the problem?
Old 10-13-2011 | 04:01 PM
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Originally Posted by Karack
but why ignore the fans completely? it's not difficult to rule them out and various climates give different results with the fans off, granted those temps are not super sky high but they will rise more rapidly if the a/c is running and not drop as much at freeway speeds.
Agreed, the fans are easy to rule out, and is something that is worth checking. I am being told elsewhere that the grommet problem is "really common" to 8s, which is surprising to me as I've never before seen it mentioned in the past 4 years of basically watching the forums all day (I get bored at work )

I agree that the A/C can impact the temps, although at the ambient temps he is at, it won't impact them nearly that much. I have a fan trigger speed adjustment through the AP, but the rest of my system is stock, and well worn as original equipment with 86,000 miles. At highway speeds in 70F temps (when fans would be worthless), I sit right at 180F. In the city, the lower trigger speeds keeps me under 195F, though if he doesn't have that then he would sit higher (understandably). With the A/C, I still sit at 180F on the highway, and more like 200F in the city.

Rust in his coolant could be affecting the heat capacity of the coolant, in which all bets are off. The symptoms of when it changes and how much tells me it's just an inefficient radiator due to airflow, and even the air volume of highway speeds isn't helping that much, so too much air is being rerouted around it for one reason or another, and not enough is going through.




OP:
Yes, if there is any contamination in your coolant, replace the coolant.
Old 10-13-2011 | 04:04 PM
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Originally Posted by RIWWP
Agreed, the fans are easy to rule out, and is something that is worth checking. I am being told elsewhere that the grommet problem is "really common" to 8s, which is surprising to me as I've never before seen it mentioned in the past 4 years of basically watching the forums all day (I get bored at work )
i suppose it's my bias seeing that the radiator is laid very similar to the FD, i have seen half a dozen of them fail for similar reasons and one RX8 with a fan melted off the housing and the other side seized up with a grommet laying on the radiator. the radiator is laid in a way that just about anything can fall into it and there is many rubber grommets on the engine lid and airbox that pop off easily. if one fan fails the other is usually going to follow very shortly.

Last edited by Karack; 10-13-2011 at 04:07 PM.
Old 10-13-2011 | 04:08 PM
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I did a Google search of the site, and I do see many threads on those grommets, so I do have to stand corrected on that possibility.
Old 10-13-2011 | 04:10 PM
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no worries, we're here to give possibilities not argue who is right. i just like to focus on the easiest solutions first rather than some of the people on the 7 club who will have you tearing apart the car creating more issues without a second thought. pulling the airbox is about as easy as it gets and gives full access to the driver side fan and a slight view of the passenger side, the driver side usually being the culprit if it is an issue.
Old 10-13-2011 | 04:11 PM
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Hmm the radiator is only a year old. I'll have it checked out again tomorrow hopefully Ford will check it for me, no Mazda dealership within 75 miles of here and no shop will touch it in this small town. My car's AC doesn't work too well depending on the temps outside, if that helps any. No heat whatsoever, something I was going to have Mazda check out before the verheating problem.
Old 10-13-2011 | 04:15 PM
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Originally Posted by Gauge
Hmm the radiator is only a year old. I'll have it checked out again tomorrow hopefully Ford will check it for me, no Mazda dealership within 75 miles of here and no shop will touch it in this small town. My car's AC doesn't work too well depending on the temps outside, if that helps any. No heat whatsoever, something I was going to have Mazda check out before the verheating problem.
if you have the fan set to defrost(possibly some other settings as well but i haven't paid attention on the 8) it will attempt to turn on the air conditioner to dry the windshield.

just putting up some thoughts as far as the clicking sound is concerned. you can easily just watch the a/c compressor and see if the clutch is locking and unlocking, spinning the pump randomly.

Last edited by Karack; 10-13-2011 at 04:18 PM.
Old 10-13-2011 | 04:16 PM
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Originally Posted by Karack
no worries, we're here to give possibilities not argue who is right. i just like to focus on the easiest solutions first rather than some of the people on the 7 club who will have you tearing apart the car creating more issues without a second thought. pulling the airbox is about as easy as it gets and gives full access to the driver side fan and a slight view of the passenger side, the driver side usually being the culprit if it is an issue.
Agreed, he should pull it when checking for the radiator sealing foam bits as well.

Originally Posted by Gauge
Hmm the radiator is only a year old. I'll have it checked out again tomorrow hopefully Ford will check it for me, no Mazda dealership within 75 miles of here and no shop will touch it in this small town. My car's AC doesn't work too well depending on the temps outside, if that helps any. No heat whatsoever, something I was going to have Mazda check out before the verheating problem.
I assume you mean not much cold? (rather than heat)

This is all something you can check yourself though, and I'd say it's reinforcing that you have too many A/C condenser vanes smashed flat. Most (but not all) of the radiator air has to pass through that before getting to the radiator. The A/C condenser not letting enough air through will affect A/C efficiency and coolant temps.
Old 10-21-2011 | 02:41 AM
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Well I've been looking around and I know for sure I have a leak somewhere, I can smell coolant when I'm stopped and when I had the hood up today looking around. Would a leak itself cause it to overheat even though there is still coolant flowing? I've also notice I've lost about a quarter of coolant since I refilled last Wednesday. I'll keep searching for the leak. This morning it was 43 degrees and the car ran around 182 during a 10 min trip. Not bad but not normal. The otherday during the same trip it was 63 and water temp was 188 and oil temp was 170.

Thanks so far guys.
Old 10-21-2011 | 04:35 AM
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Have you checked the coolant tank cap? Make sure it tests to the correct psi rating. A weak coolant tank cap can allow coolant to escape under lower temps. Could also allow coolant to reach a boiling point at a lower temperature. Increasing internal cooling system pressure.
Also check the tank under the cap (neck to tank seam) and make sure it's not cracked.

And check your radiator behind the grill and make sure nothing is blocking it.
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