High oil/coolant temps help
 

I did search and couldnt find anything. I have had a problem ever sence the motor popped.

Here are the problems with the car. I had the motor rebuilt about 8K miles. It was rebuilt and set up for a single turbo setup. The shop put in a horrible oil thermal pallet and that caused the motor to pop. Blew a rotor seal and was letting compression out of the main rotor.

Another shop rebuilt the motor again. Ever scene the motor popped the oil temp is going up to 220. Water is going up to 210 or 103-104 on the power fc.

I have replaced the oil coolers with setreb 25 row oil coolers, a new thermostat on the oil system, and drained the oil system.

Here is what is on the car

Fresh rebuilt motor
garret t04s turbo
ron davis radiator
2Xsetreb series 6 25 row oil coolers
feed front bumper
fmic greddy
all the supporting mods.

before the motor popped I had duel B&M oil coolers and the car ran fine. I dont know what is causing the car to run hotter. car would run fine up the mountains and the oil temp never got over 200 and the water temp never got over 195. Now I cant go up any grades in the car or the car will run even hotter

Have you had the car tuned?
What coolant/water ratio are you running?
Have you checked that the fans operate properly at all speeds?
What about the coolant T-stat?
Why did you change oil coolers when the B & M were sufficient before?


I understand that your saying you didn't have this problem before, but your FMIC isn't helping anything.
Have you taken it back to the builder and asked them?

running water wetter no coolant and no t-stat. car isnt tuned because its not broken in yet. fans start at around 190 i think and run very good. I thought the oil coolers had stuff in them and wanted to run the best oil coolers and not have to worry about them again. I can see the oil temp rise causing the water temp to rise. the over heating is due to the oil temp.

Oil temp will naturally rise first and is usually higher than coolant.
Running with no t-stat allows some coolant to bypass the radiator, so I'd put one back in.
Do you have all three fan speeds?

Is EVERYTHING ducted properly so that no air is escaping around the radiator, oil coolers, etc.?

If it is not, then that would easily explain your cooling problems.

I dont know if i have three fan speeds? how do i check? I will look into getting a new t-stat. Can i get a lower temp one? if so where do i get one? mazda? Thanks for the help

I will install all the correct ducts and trays. I have an undertray and oil cooler ducting that i didnt install. I was getting tired of putting them on and taking them off. I am also going to remove the oil t-stat and see if that is messing up the oil system. I am so tired of trying to figure it out.

What are the ambient temps in Tuscon these days?

The temps you listed are not overheating, especially if its 110 degrees out. Recheck your fans. I set mine (on pfc) to come on at 85c.

I am in las vegas now and the temps outside are hot. My temps were real low and never fluxed before the motor went. My oil temps sat at 180 and water at 175-185. Now i cant go over 70mph before the temps start to rise and will continue to rise until I stop. My oil temp would go up to 260 before it would level out and stop climbing. That was before the rebuild. I dont like the oil temps that high and shouldnt be that high if i have two oil coolers. Also I run the car with the heat on high all the time. That is the only way to drive the car. I cant boost the car very much and if i do boost then it is for a short time. Basically the car acts like it only has 1/2 an oil cooler.

I dont know what the fans are set to but i think it is 180? I know that the shop wants to keep the temps low because it is vegas and was meant to be a daily for me. I bought everything to have it be one. The shop doesnt like the temps either but they are stumped on what is causing it.

If it is the water that is causing the over heating will the oil absorb the heat? If my water pump or radiator are not working will it cause the oil temp to rise?

Sounds like you still have air in the coolant system. That usual symptom is getting hotter as speeds increase - assuming you aren't beating on the car.

YOur water pump might also be slipping. I'm assuming you aren't running an air pump with the single turbo kit.

Do install a new thermostat, rebleed the coolant system. There are a few companies that make 180* tstats - Pettit and Mazmart.

Stock fans engage at around 200*F. Check that both are engaging. Whatever you are using for engine management should allow you to configure the engagement temps.

Oil and coolant temps are very influenced by each other.

I would bet $ that this alone will cure the temperature problems. Getting hot at higher speeds without a lot of load on the engine is a definitive symptom of either a blockage in the cooling system, or air not flowing through the coolers. At higher speeds, most of the cooling is done by high-speed air forced through the coolers, not drawn through by the fans. IMO, if the fans are needed at high speeds, there is something wrong with the cooling system. Most racecars do not use fans at all. Air follows the path of least resistance, and if the ducts are not there, that path will be around, not through, the coolers.

^good catch. I didn't notice that comment.

I dont know it this matters but the oil coolers are installed right behind the bumper. i dont think i would need a duct and if so they are behind the coolers. here is a pic of where they are mounted circled in red. as far forward as they can be.

Close only counts in horseshoes...

Unless my eyes are playing tricks (the photo is pretty dark), I can see pretty large gaps between the bumper cover and the oil coolers. IMO, these gaps are large enough so they will allow most of the air to bypass the coolers. Believe me, it doesn't take much of a gap to screw things up. Ducting is much more important on the high-pressure side, compared to ducting on the outlet, where the air has already been slowed down by the cooler and is not at as high a pressure.

I've seen cases where just a 1/2" wide gap at the rear edge of a 2-ft long angle-mounted radiator was enough to cause overheating that was eliminated when the gap was plugged.

Dave

^Agreed. I would have thought the need for an undertray was obvious. Especially if one is concerned about overheating. Guess not.

As far as a lower temp t-stat, just use the OEM one. One thing you could do however, is get a 89-91 FC thermoswitch to replace the stock one. That will lower fan threshold temps from 108 C. to (IIRC) 95 C.

BTW, by coolers I mean oil coolers and radiator... Sorry if this was not clear.

Dave

By close i mean i have rubbed some of the bumper off. There is less than a 1/4 inch gap.

I have a power FC and set the fans to come on at around 85. I had an undertray on and the temp raised a little bit. I dont know if it is because the fmic is pressed tight on the bumper as well

BTW thanks for all the help. my water belt was a little loss and was slipping. tightened it up and made the car run better.

You should be using an idler pulley for more contact of the water-pump pulley.

I just ordered one. I cant wait to put it on and see if it fixes the problem.

As stated earlier, cooling will not work properly with no undertray.

+1 for this. Witnessed this first hand a few years ago when I took a test drive without the undertray on. Had +20 temps almost compared to with it installed.

Also, As others have already said, if you really want to get the most out of your expensive new coolers (oil and coolant) they need to be 100% sealed and ducted to the nose of the car. You will notice dramatic changes in the effieiency of the coolers. This will cause no need to run things such as no t stat, which pretty much just makes the car warm up slower.

Your kit shipped out yesterday, hope it helps with your problem.

Dan

spell coolant right in your subject line
not bc i'm nitpciking
but for those who may search for coolant problems later use the "Search" button

There's a lot of good advice/help in this thread

Sorry i misspelled coolant. Tightening the belt lowered the water temp but the oil temp is still high. How hot can the oil run before its to high and i should start watching it? How high before it causes damage? Thanks everyone for your input.

If you want to correct people's spelling, you should learn to spell nitpicking :)

my pal called mazda for an undertray since mine is missing and they wanted $400. thats just insane :\

I know that shine made one for the FEED front bumper. That is where i bought mine from. Mounted up real easy.

cool, ill have to check them out then because i need one

Buy a used one in the parts section.

Undertrays are a dime a dozen. They go for at the most $125 if Im not mistaken. Im selling one right now as well.

So I installed the undertray. moved the oil coolers up so they are sitting on the bumper. Installed a pettit racing 180* thermostat. burped reburped and the burped the system again to remove all the air. Took it for a spin and the car over heated again.

oil was 220 and water was at 210 and was rising. This was up a slight up grade. Going home it still ran hotter than i wanted it but water was still close to 210.

Could it be the water pump?

If the water system isnt working does it transfer heat to the oil?

Also have a FMIC flush with the bumper could that cause the car to not get enough air to the radiator?

I have the a/c "cooler" (sorry i dont know what its called) sitting in front of the radiator. any effect on the cooling system?


As soon as i shut off the car the oil temp drops real quick. water just sits there. I have to circulate the water to get it to cool down. I think its the water pump but not sure.......

IIRC, water pumps leak out the weap hole on the bottom of the water pump behind the impeller when they are bad. Any leakage from there?

I have a brand, spanking new water pump in the garage if you are looking to buy one.

No leakage that i can see. I thought maybe it got hot and isnt pumping as good but still together if you know what i mean. but i have done so much i am lost now.....

Have you verified that the water pump spins freely with the belt removed? Might be something to check if your suspect of the pump.

Also, are these test drives on the highway at highway speeds for extended periods of time? Or low MPH, stop and go situations?

Reason I ask is if the rad fans are/ are needing to engage. Regardless of if the fans are working properly or not driving at highway speeds should be able to tell you if every other piece of your cooling system is operating the way it should...

Do you have a yellow Lisle funnel that you can insert into your fill neck and run the car to see if your're getting air bubbles? I hate to even mention this, because if you're seeing tons of air bubbles the shop that reassembled your motor in Vegas could have pinched an O-ring on reassembly. If you're getting any kind of "pressurization" in the engine, that could cause the overheating that you're observing. Just a thought. Also not sure how and where you're driving in Vegas, but if you're stuck in traffic for any length of time on the strip and get heat-soaked, it takes a lot of time to bring down your temps. Just a brutal city for rotaries, FDs in particular.

Oil temps above 230 make me very nervous. 260 for any prolonged period of time will do damage to your bearing surfaces IMO.

The water pump spins freely and there is no play with the shaft.

I am driving on highway speeds 70 mph or less in 5 gear for a 2-4 mile road. temps are 200* oil and 180* water before i get on the high way and move up as soon as i get on the highway. Fans kick on at 180* ish.

If the the O-ring was pintch then i would be using coolant correct?

If the motor is bad the shop will rebuild the motor no questions asked. I know this because they just rebuilt a FC motor that had less than 2,000 mile on it. Young kid that was drifting it with no ECU and higher boost levels. They pulled it and it is in cali right now getting rebuilt.

I only had high temps over 230 before the rebuild. I dont letting the oil temp get over 230 or the water temp to go over 215.

That is very interesting. Def not something to do with the fans then. Are you running an AST? Or have you deleted it?

I dont think I have an AST. Do you need one on a single turbo? Fans work i know this and the temps drop fast when i am at idle.

Doesnt have to do with the turbo. Any fd can be run either way, just depends on what you wanna do. I just remember hearing, and I also witnessed it first hand, that cars with no AST have a harder time burping the system. My car used to have no issues with this when I had an ast, but when I deleted it it was a little more of a pita. Have you followed the standard procedures to remove the air bubbles? If so, what method did you use?

Then its deleted. I dont have an AST. I have the shop in vegas burp the system. I dont know how they do it but i hope all the air is out of the system. Would this explain the high oil temps?

It wouldn't be "using" it per se. Exhaust would be entering the cooling system and pressurizing it, hence it would probably start blowing out the overflow.

OK, so your current temps running slowly (50 mph or less) are 180 ish water and 200 oil. That's fairly typical for your climate, especially considering that you're running a front mount. If you've reinstalled the undertray, make sure to block off any places where air can escape underneath the car to keep air moving through the IC, rad, and oil coolers. Have you checked your coolant cap to ensure that it's holding pressure?

Have you tested the cap? I've bought several "new" ones from Mazda in the past that I tested and they wouldn't hold the proper pressure. Put your ear close to the cap following shutdown and see if you hear any slight hissing sounds. Is your coolant level staying topped off the day following a drive (i.e., when completely cooled down), or is your overflow slowly filling up and are you constantly having to "top off" your system? Just trying to kick every possible tire. Is it possible that the thermostat is somehow installed improperly??

Also might be helpful if you post up the ambient temperature when you're taking your test drives...

WOW... check that out... my 1000th post. :)

Hey Curt... another thought. If you're doing these tests above 100F and are taking the car up some fairly long uphill runs, you'll be hard pressed to keep her "cool" or even steady in the summertime when it's this hot. The FD is notorious for coolant temp "creep" in the summertime when temps get above 100F outside.

By long hill what do you mean? I take it up a drive on the highway and the only way i know its a hill is because the car will heat up. It is not a noticeable hill. I take it for a two mile drive and the car will overheat. Not a long trip at all i dont think. It would be like driving in tucson and the car overheat on the approach to Mt Lemmon and having to pull over before i even get to the Mt.

Would this cause a high oil temp?

I have th undertray that fits tight against the bottom of the car. I am about to pull the A/C out so there isnt anything that obstructs the flow of air into the radiator. I will check the cap on the today after i drive the car. I dont have to top off the coolant everyday. Thermostat is installed correctly.

Also temps are with the heat on full blast on defog.

By long hill, I mean a steady uphill grade for several miles. This will definitely cause your temps to start climbing, especially when your outside ambient temps are above 100F. Once ambient temps drop below 90F it doesn't seem to climb as quickly (in my experience). With dual oil coolers your oil temps should pretty closely parallel your water temps, with oil temps being MUCH cooler during the winter months. Heck, I almost need to block one of my coolers off in the wintertime just to get the oil operating temps in the 160F+ range while cruising. Oil temps will be slightly higher than water temps under LOAD, but should come down quickly once you start heading downhill and remove load, even in summertime.

Is your radiator still mounted in the factory position?

There is your problem right there. Look carefully in the t-stat housing. If you don't have a t-stat, 80% of the hot coolant will not flow to the rad but straigth back into the engine.