Overheating issue
Thread Starter
Racer
Joined: Jul 2009
Posts: 277
Likes: 7
Overheating issue
Hey guys, new to the forum, name's Gil. I have an `04 Z06 with a modified STS twin turbo setup.
I just recently finished build my motor from forged internals, cam, valvetrain etc. Started right up, instant oil pressure, no leaks, everything checked out. I also have a 180 degree thermostat and fans are programmed to turn on at that point, which they do. After about 10 miles of driving I noticed temp kept slowly creaping past 230 and would have kept going. If I just let it idle it will do the same just takes ALOT longer. Hopefully I'm missing something dumb but haven't come across it yet. Has a new Ron Davis radiator, waterpump is good, no external leaks, and system holds pressure. Hoping my thermostat might just not be opening all the way so I'm changing it tomorrow at work. Burped system numerous times so its not an air pocket. Anything else I'm overlooking? I need to break this motor in and get tuned so I can come out and play!
I just recently finished build my motor from forged internals, cam, valvetrain etc. Started right up, instant oil pressure, no leaks, everything checked out. I also have a 180 degree thermostat and fans are programmed to turn on at that point, which they do. After about 10 miles of driving I noticed temp kept slowly creaping past 230 and would have kept going. If I just let it idle it will do the same just takes ALOT longer. Hopefully I'm missing something dumb but haven't come across it yet. Has a new Ron Davis radiator, waterpump is good, no external leaks, and system holds pressure. Hoping my thermostat might just not be opening all the way so I'm changing it tomorrow at work. Burped system numerous times so its not an air pocket. Anything else I'm overlooking? I need to break this motor in and get tuned so I can come out and play!
Thread Starter
Racer
Joined: Jul 2009
Posts: 277
Likes: 7
I do have a front mount intercooler and it never ran hotter then 190 before the build and I have also tryed letting air out through that crossline on the valley cover. As soon as I cracked it open coolant came right out.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 326
From: CA.
St. Jude Donor '13-'14-'15
Sounds to me like you have an airflow problem with incoming air across your radiator--At idle there is NO boost !!! so if its over heating at idle the cooling system is just not working----I would try a 160 thermo---That's all I ever use-even on Silverados--They never run that cool because of the logistics---My cars/trks all run about 185* even with a 160 thermo---You may have an air pocket that hasn't bled out as mentioned---Were you able to retain most of the radiator shrouding ?? The more stock the shrouding the better the airflow-- Did you check to see if indeed the fans are coming on ? I would setup the fans with a 180 thermo as such #1 on at 190 off at 181 #2 on at 200 off at 191
Check for debris in your radiator front---Did you retain the front spoiler ?? Often aftermarket frnt spoilers are notorious for making the air pass around the Radiator and not thru it-----
Also the inter-cooler placement could be blocking off the radiator airflow at idle --or low speeds
Check for debris in your radiator front---Did you retain the front spoiler ?? Often aftermarket frnt spoilers are notorious for making the air pass around the Radiator and not thru it-----
Also the inter-cooler placement could be blocking off the radiator airflow at idle --or low speeds
Thread Starter
Racer
Joined: Jul 2009
Posts: 277
Likes: 7
Both fans turn on at 180. Nothing has changed with my cooling setup outside of the motor. All i did was rebuild my motor internals. I even flushed radiator while it was out and cleaned fins. I washed my waterpump at work with our parts cleaner so im hoping maybe that did something to male my thermostat stick.
Intermediate
Joined: Mar 2012
Posts: 27
Likes: 0
From: Caddo Mills Texas
Try 2 bottles of Redline Water Wetter. It is a life saver in Dallas, where its 157 degrees
from May thru October. Let car cool, drain your radiator, add 2 bottles of WW and top of radiator. Let engine warm up and re-check coolant level. I originally tried this in a 1994 6 speed coupe, with constant overheating issues. I installed the 160 degree thermostat and fan relays, which helped some, but the WW knocked off about 15 degrees off the normal operating temp. Currently using this in my 02 Z06, wifes-2009 Accord, kids-2002 Z28 and 2003 Ram 2500 diesel 4x4.
Just my .02
from May thru October. Let car cool, drain your radiator, add 2 bottles of WW and top of radiator. Let engine warm up and re-check coolant level. I originally tried this in a 1994 6 speed coupe, with constant overheating issues. I installed the 160 degree thermostat and fan relays, which helped some, but the WW knocked off about 15 degrees off the normal operating temp. Currently using this in my 02 Z06, wifes-2009 Accord, kids-2002 Z28 and 2003 Ram 2500 diesel 4x4.Just my .02
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Thread Starter
Racer
Joined: Jul 2009
Posts: 277
Likes: 7
Are both fans supposed to always run together wether on low or high? I lnow they both kick on around 180 but its hard to hear if they go to high (cars kinda loud) Thinking maybe they might not be switching to high because I took it on the highway today as it was approaching 217 then it dropped down to low 190's. Is it possible I lost my fan tune somehow while battery was disconnected?
Thread Starter
Racer
Joined: Jul 2009
Posts: 277
Likes: 7
Ok heres the latest...fans are definetly getting there 14V each. I noticed they blow alot harder if I use them as blower fan rather then pullers so I mounted them in front and things got a LITTLE better. Stop and go it will get hotter then it should but drop down to 180's if i'm cruising at about 70mph. I let it idle for too long and it very slowly makes its way to 230's and will not come back down. Really seems like fans at this point so Im going to try putting a stock fan assembly back in. The high speed fans I have now blow 2,000cfm each but they're mounted directly to radiator with no shroud so they cant pull the full surface area of the radiator.
Thread Starter
Racer
Joined: Jul 2009
Posts: 277
Likes: 7
These are the fans I have. Not cheap but they work very well:
http://www.dewitts.com/products/all-c5-spal-fan-upgrade
http://www.dewitts.com/products/all-c5-spal-fan-upgrade