Coolant temperature issues

[TuRBoTaLooN]

I wasn't sure where to post this, so I figured the newb forum was a safe bet. Now, as a precursor, I am a seasoned DSMer and I have read a lot before posting, so please let's keep this thread helpful. Thanks!

I've been struggling with coolant temp issues now for a while. I attempted to make some heat shields and some different fan combinations, but it still would run hot. Not necessarily overheat though.

So I got a new OEM thermostat, put two 12" slim fans on (don't know what cfm rating), filled with 50/50 coolant/water and a bottle of water wetter. Left the cap off and ran to temp, had the thermostat open and close twice with the heater on full blast and squeezed the lower hose to get all the air out. Put a new mishimoto rad cap on and let it cool down. Then I started it back up once it was cool to operating temp. It went between 196 and 200. Took it for a spin and it would get up to 203 and back down to 196. Then after 5-10 minutes of driving it went to 213, back down to 206, 203, then back up to 216! Headed home and it got up to 219 at its hottest. Both fans on full.

I'm not sure what the problem is, but I do have a concern about my o2 dump tube. I have a FP3150 with a tial 44 on the side and a dump tube that lays basically right over the downpipe. Unfortunately with the fan shroud, this tube is touching the back of the one fan on the driver's side. I checked when I got in the garage and both fans still worked. Nothing was melted.

Lastly, here is some basic info on the car (instead of checking out my profile info)
2g with a 6 bolt bottom end (maybe 5k miles), new rebuilt 7 bolt head
FP 3150 turbo w/ tial 44 and o2 dump
Punishment aluminum rad with fan shroud and 2 slim fans wired together to go full on, or just off
FP 2.5" o2 housing, 3" exhaust
ECMLink v2

I don't know what my next move should be here. Any suggestions/thoughts?

 

[Texas gst]

how old is the water pump? kind of a long shot, but if the fins on the pump are getting worn and eroding than it could cool normally, but not push enough water when driving. I have only seen that problem once or twice ever though.

 

[TuRBoTaLooN]

how old is the water pump? kind of a long shot, but if the fins on the pump are getting worn and eroding than it could cool normally, but not push enough water when driving. I have only seen that problem once or twice ever though.

Thanks, but I put a brand new OEM water pump on when the motor was rebuilt.

 

[Texas gst]

well, like I said, it was a long shot. all hoses same temp? no blockage of your radiator restricting air flow. That's all I could think of.

 

[mazda-man]

Was writing about the water pump and the other guy beat me to it. Do you have the stock rad or a aluminum one and do you have a front mount intercooler or a side mount?

 

[doubleclutch99]

just a thought but are the fans pushing air out the front instead of pulling thru the front. mine were reversed and we felt like they were pulling air at first, but i had the same issue and we checked them and sure enough they were pushing air in the wrong direction.

 

[SmoochDarling]

I've had similar problems, after replacing everything coolant related, the problem has now developed into a slight HG leak. So my question, did the problems arise after the the rebuilt head was put on? Possibly it is pushing some coolant?

 

[TuRBoTaLooN]

I did not check the temp of the hoses, but I could see coolant moving with the rad cap off.

I have an aluminum radiator from Punishment racing, as I mentioned in the original post.

I double checked the fans and they are pulling air through, not pushing. I accidentally wired them the wrong way at first, then switched it.

I have a big front mount intercooler. That may be part of the problem, but I'm not even pushing the car, just cruising around town.

I had thought about the headgasket possibly leaking. I plan on doing a compression check tomorrow, but I didn't see any signs of the HG pushing coolant.

My other thoughts are getting more powerful fans. Mishimoto sells a kit where the fans pull 1300cfm EACH! Also, I plan on changing out my crappy ebay front mount with a good core from ETS as well as removing all the A/C components to free up some air flow.

 

[staztrx250]

see if the coolant lines are soft well the car is cool. If they are get a new radiator cap. If that doesn't work get new 170* thermostat. I had a lot of problems with my car running that hot with none oem thermostats. It just seems that the temp ranges were off. I put a 170* in and it never got above 200 again.

 

[TuRBoTaLooN]

see if the coolant lines are soft well the car is cool. If they are get a new radiator cap. If that doesn't work get new 170* thermostat. I had a lot of problems with my car running that hot with none oem thermostats. It just seems that the temp ranges were off. I put a 170* in and it never got above 200 again.

As I mentioned in my original post. I have a brand new Mishimoto rad cap, and a brand new OEM thermostat. Thanks.

 

[Levesque]

I have the same problem , Im runinng hot and my engine bay is hot like hell...but never over heat.

Check if theres no leaks at the 02 housing gasket or downpipe...if so all that heat is going into the engine bay.

 

[TuRBoTaLooN]

I have the same problem , Im runinng hot and my engine bay is hot like hell...but never over heat.

Check if theres no leaks at the 02 housing gasket or downpipe...if so all that heat is going into the engine bay.

It's all v-band clamps, no way it's leaking.

 

[tragdor]

What coolant brand and color are you using? Have you switched to orange since you started using an aluminum radiator? I was having temps in the 230 range. Flushed the system (including a chemical flush), replaced the thermostat (which wasn't stuck it seems), and now my coolant temps are a solid 210. I don't have a front mount yet. But the flush and switch to orange dropped the temps by about 20 degrees. This is in my scenario and I'm sure that there are risks involved with switching from green to orange. You're call. Good luck!

 

[TuRBoTaLooN]

I'm using the Prestone green stuff. Why would you switch to orange? What are the benefits?

 

[pneumo]

Do the rad hoses feel firm when hot? Or are they still soft? The cooling system needs to hold pressure when hot, which raises the boiling point. If any of the hoses are weeping a little it won't cool as good.

I'd use 30/70 mix of coolant/water plus one bottle of water wetter. Having more water will let it cool better.

Is there any shrouding or ducting between the FMIC and radiator? If there's no plastic duct covering the area between the bottom of the fmic and the rad, then you're loosing airflow. Just a simple flat piece of plastic sheeting covering the gap between the bottom of the fmic and rad will send more airflow through the rad. Try it, it makes a difference.

Check the torque on the headstuds to make sure they're still tight. Sometimes they need a re-torque after the first heat cycle.

 

[TuRBoTaLooN]

Good info man. I re-torqued the head studs after break-in, but I will check them again. I didn't feel the hoses either, so I'll check that too. They are new, so I don't imagine they are leaking!

Another thought came up today. I have a 6 bolt block and 7 bolt head. My OFH is externally cooled, so no water lines run to it. The turbo uses 2 lines. This still leaves one coolant "port" on the water neck that I plugged with a vacuum cap and a worm clamp. Maybe it wasn't holding pressure? I plugged it with some JB weld and I'm going to let it cure overnight. I was going to buy a pressure test kit, but it was $60 at harbor freight!!

 

[Silver99GSX]

Are you running your A/C? You could try placing one fan on the driver side front of radiator Pushing and the other one pulling on the engine side (passenger side) of the radiator. If you are running A/C do the same set up but put the other fan pushing threw the A/C condenser. It help me big time. Plus I'm running one 14" and one 12" both are 1550cfm. Try it out might work for you. Cause the intercooler is taking most of the air coming in.

 

[nlzn]

Just an FYI:

My car would overheat with two 12" slim fans (unshrouded).

Tried everything, installed stock fan with shroud, overheating gone.
Moral is some slim fans suck.

 

[97gst_spyder]

His have a shroud. I would check the ducting from the fmic to radiator. If that's missing it will screw the airflow up. Lots of guys in FL have issues with running hot w/o it.

 

[TuRBoTaLooN]

I have the A/C components there, but I do not run it. I'm in NJ and it's between 40 and 50 outside on most days right now. So its definitely not hot out.

There is no real "ducting" between the fmic and rad, which is part of the problem I'm sure. Plus I doubt my fans are pulling much air. It just seems like there is something wrong...

 

[pneumo]

I have the A/C components there, but I do not run it. I'm in NJ and it's between 40 and 50 outside on most days right now. So its definitely not hot out.

There is no real "ducting" between the fmic and rad, which is part of the problem I'm sure. Plus I doubt my fans are pulling much air. It just seems like there is something wrong...

Your car is running within acceptable temp range, it's just a little too hot for best performance. I wouldn't consider it 'overheating' since everything works after it cools down, and it cools down on it's own. I've run my car consistantly in the 210-225 range in summer. It might just be several little things are adding up to make it run hot. Take care of the issues posted above and see how it goes.

also make sure the small hoses going to the throttle body and heater core are leak-free.

 

[TuRBoTaLooN]

Thanks, but I don't think the car should get up to 220 with a light ride around town. Granted under stress I can see it getting that hot, or if it was summer, but it is very cool out. I guess my plans are to get fans that flow more, remove the A/C system, and re-route the o2 dump farther away from the fans.

 

[Absit]

And duct between your FMIC and radiator..

 

[TuRBoTaLooN]

Just an update. I did a pressure test on the cooling system and the rad cap. Both held 20psi fine. The cap is rated for 19.

I'm in the process of removing the A/C system and I will do a compression test later this weekend.

 

[ryerock79]

I am having the same issues out of my 92 talon. I am new to this site and just wanted to say thank you for all these helpful tips. I now have a direction to go!