My issue seems to be different from others that I have talked to and read online. Here it goes...into as much detail as possible....ask what you may....

First, got my car back and about 500 or 600 miles later on the new V2 build my car's coolant started to overheat and the temp outside was in the low 80'sF. I noticed it after driving about 10-15 minutes with stopping at red lights and stop signs. Pulled over and let it cool down. Of coarse the first thing that comes to mind is air in the system or coolant leak. The first thing I do is check the ground for leaks and the coolant hoses for cuts or anything. The only thing I saw when I pulled over was a low coolant level (just below the low line) and the bypass hoses where bulging from behind the V2 main, black, bracket with the pulleys on it. (you know the main face plate thats with the SC setup) I don't know if everyone who has a V2 has the bypass hoses squeezed between the bracket plate and the engine and pressing against one of the screw heads on the bracket near the SC. (ill post pics when I get home) but there were no leaks or anything.

I called Sharif to see why my car was overheating after I got it back from them. He said to see if my heat blows hot air and if it blows cold air supposedly there's air in the coolant system. Well my heat blows scorching hot air so thats not it...I turned my car back on and left the heat on then turned it off and it wasn't over heating at the time so I drove home and it was good until a couple days later.

I was driving on the highway for 5 hours or so to VA from NC and it didn't over heat again. Spent the night at my parents house then went to the beach and that was about 3 hours away on the highway and no overheating. Get to the boardwalk strip at VA beach which is like driving at 15-20mph stop and go and it was 97F outside. I noticed the coolant is almost borderline overheated so I park in the parking garage as quickly as possible. Pop the hood and the coolant is boiling (litterally) in my coolant reservoir tank. Go to the beach for a few hours and come back to notice the coolant reservoir cap was cracked around the corners of it due to the pressure from the overheating and boiling. So I'm pretty sure thats how all the coolant exited the system when I got back because it was on the ground and all over the place. Put more coolant in both the radiator and the reservoir and turn on the car. Let it get to operating temp and turn the heat on blast and rev'd the engine to 3000RPM and held it there for about 5-10 minutes. Saw no problems so I got in the car and left the garage. (Saw a black G with black faced wheels with a copper colored wheel lips on the boardwalk strip so whoever that was those wheels looked sick. never seen that before.) anyways looked down at the coolant and it started to over heat again after driving for about 5-10 minutes on the strip which was stop and go at 15mph. Pulled over when it started to overheat and put my heat on blast before I turned it off. Funny thing is it stoped the coolant temp from escalating any further. It stopped at it's current position. At this point I'm thinking....wtf is going on....I look under the hood and the coolant is still at the current level it was when i refilled it. I drove off with the heat still on blast so the temp doesn't continue to rise and what do you know....the coolant temp goes back down to normal operating temp once I moved more than 500 feet at least at more than 20mph. I stop at a light and the temp is a couple notches above normal still. I get back on the highway and it's back to normal temp and I don't need the heat on when I'm on the highway. It stays at normal operating temp when I'm on the highway but not when I'm in traffic....weird....didn't have an issue again until today.

As I was on the phone again with Sharif to tell him this story he said he is going to send me a funnel to do a procedure to get the air out of the system and to check to see if there are non-stop bubbles coming from the radiator (after doing this procedure for 30 minutes) leading to the possibility of a crack or opening allowing air to consistantly enter the coolant system. Anyways while I was on the phone with him again it started to over heat again........This time the temp outside was 81F and I was driving my car for about 10-15 minutes and I was sitting at the bank line (at idle) for about 10 minutes until it started to overheat. I turned on my heat at full blast and it stopped increasing temperature like I thought it would do from figureing it out from yesterday.

Now that that's out of the way here are the key points to this post:
-it overheats when idleing for long periods
-it doesn't overheat under normal driving (without stopping)
-it started about 600 miles after V2 setup install
-the bypass hose is pinched with the possiblity of puncturing the hose from a screw on the V2 main face bracket.
-the fan shroud was removed so 2 12 (or 10, i forgot...lol...) inch turbo fans are attached directly to the koyo slim radiator.
-the fans turn on when engine gets to certain temp like normal.
-maybe Strup headers heat dissipation+V2 heat dissipation+less fan effectiveness create to much heat when at idle or not moving fast enough/long enough for adequate air flow for cooling?

After I bleed the cooling system with the suggestion by Sharif and it doesn't fix it then I'm in a complicated dilema as you can tell which is why I'm posting this now just in case thats not the fix for it. All help is appreciated and I'm sure someone out there has the fix for this. I just haven't heard or seen anyone with this problem before. Thanks.

 

you sure your thermostat isnt taking a crap?

 

whatever.

 

One thing I don't know your saying is hot air with no a/c on.....how is anything going to come out of the vents if it isn't turned on?....I know there is "A/C" and "A/C ECON" settings when I turn it on to 90 degrees. But like I said before it's scorching hot air coming out when my car starts to overheat. When I turn on the heat with it not at operating temp, at operating temp, or above operating temp I get hot air when I turn it on. My radiator cap is Mishimoto and is 19lbs I believe so it's not that. It could be my thermostat if it would overheat from it not opening up when it's suppose to at operating temps but if you read what I said it goes to operating temp then after driving it for some time it starts to over heat then it will stop overheating when i turn on the heat on full blast then start driving without stopping like a highway....thanks for the suggestions though....those have been analyzed by myself (being a diesel mechanic) and Sharif and he is set on there being air in the system as well even though I get hot air when I shouldn't due to an air pocket supposedly.any other people with word?

 

to add to the thermostat thing.....unless you can provide some complex information then don't say it's the thermostat. Nothing will make it open and close when it feels like it during driving. Once it's open then it's open. The heat being on blast, being at idle/traffic-driving for long durations, and driving above 30mph constantly (highway) can't have an effect on the thermostat opening and closing when it pleases changing the coolant temp. Thanks for the input but thats cancelled out. I was going to get a Nismo thermo with my setup but supposedly they are on back order everywhere. I was thinking about maybe it's the water pump but then it would overheat all the time even when I'm driving at high speeds under boost at 6500 RPM. But when I run it like that the only temp that changes is my oil temp and it only goes up 2 degrees F. SO IT ONLY OVERHEATS DURING IDLE AND NO OR SLOW MOVEMENT.

 

Are BOTH fans operating in the same direction? I believe they opperate at 2 different speeds also......are yours running in the "fastest" mode?

I am only guessing . . . you mentioned you have aftermarket which I believe requires some "new" or "different" wiring.

 

whatever.

 

Same direction?....yeah they only go one direction. Before I sent my car to them it was rewired correctly. Sharif said there was a fan problem and that they didn't come on when the A/C was on but I never turn on the A/C. I always ride with the windows down. The fans turn on when the engine gets to a certain temp like normal and I can hear them come on and get faster from inside. The fans work but I didn't look at them thoroughly with the car running and/or overheating since I got it back. Some reasons are when the car is overheating and I hear the fans I don't think the analyze them, when the car is overheating....its f***ing hot under there....lol, and they didn't rewire anything from what it looks like. I haven't had time to get under my car take off the underpanel and look at everything yet. I might wire it directly to power so that they are on at high speed all the time.

 

Seems like as long as the car is moving and forcing air through the radiator you don't have any problems, which would make it seem as though the fans are either not working properly or not efficient enough. Removing the stock shroud from around the radiator is probably making it worse, without it there is nothing to contain and direct the airflow to where it is most needed (ie. the radiator).

What type of fan set up are you running? And at what temperature are the fans kicking on? You may need to look into getting a fan controller that will allow you to lower the temp at which the fans come on.

It could be an issue with air pockets in the coolant but with so many issues at low speed it seems like air flow is a problem. Have you ever taken the pressure cap off with the engine cold to see if there is pressure present? A lot of times that can be a sign of compression getting into the cooling system which could cause the same symptoms you're describing.

 

I would think it might have to do with the fans as well. The design for the shroud is for the flow of air leaving the radiator creating some type of effect to make the fans operate more effectively. I also noticed that the coolant level is lower than it was when i filled it yesterday. It went down about 2 inches. I was feeling around the bottom of the radiator and there is substainstially more residual coolant on the driver side by the radiator drain port. (hole with aluminum plug in it) I know on my other radiator (mishimoto) the drain port plug wasn't on very tight when I first installed it. maybe thats the case with this radiator causing a leak and allowing air to continually enter the system causing overheating when i'm at idle. the part i dont know is if the air pocket effects the engine temp when im driving on the highway or on the road with little traffic and stopping.
if the case is the drain port plug then I would expect tons of other people who get aftermarket radiators to have the same problem especially if it happens to me when i get my car back from a very well known, respected, experienced shop like Forged. so i don't think its that port but who knows....people make mistakes.
although i still believe it's revolved around the fans and adequate air flow. the engine oil temp is perfectly normal. the coolant is the only aspect being effected. a/f ratio is good. the SC belt needs to be tightened. other than that everything else is good.

when i just looked under the hood the fans have been messed with as far as wiring goes. it might have to be completely rewired with a fan controller like you said before and get the custom aluminum fan shroud that we can use with the V2 that on the market.






if anyone has with a V2 has this kind of coolant bypass routing let me know. It's worse as the engine is on and the heat expands the lines and the coolant applys the outward pressure against the screw head.

 

Suggestions:

Pressure test your cooling system.

Make sure both the radiator fans are coming on at the correct temperature, going the correct direction, and going the correct speed.

 

seems like u need to upgrade to some slim fans with better cfm. I had the same issue in the HOT summers hitting over 100F and the car would over heat on local driving but once I hit the freeway it dropped down. I swapped to a bigger rad and bigger fans and it never happened again.

 

^^^

he should NOT be needing to do that at all though...i wonder why you had to do that at all....specially considering he is just using a S/C... an oil cooler maybe, on top....or a rad, but the rest is in the install and tune......
I dont like just keeping buying aftermarket stuff on the "thought" that that is the real issue and it jsut gets people to spend more unnecesary money

 

just a heads up, i do have the same setup. i'm not sure if it's fine or not.

 

Unless that hose is being pinched shut the bolt head should interfere with coolant flow, although I don't like to see a bolt and a rubber hose in contact with each other. Vibration causes friction, friction causes holes, holes cause...well you know.

I would pick up a rubber lined adel style clamp (most hardware stores will have something) and put it around the hose and mount the hose to that bolt. This is what I'm referring to.



Back to your original problem....

I would definitely check out the fans, if you have an infared thermometer you can use shoot the radiator and see what temp it is at when the fans come on to get some idea if a fan controller would be of any benefit or not. I agree with someone else's post that it should not take anything extreme to cool your set up. What brand of fans are you running? Perhaps a part number so we can compare the flow capabilites of them.

 

If you can't find a nismo thermostat, you can get a mishimoto for half the price. They list at $80.

 

well it seems like some of you aren't reading everything but i can understand that because it's long but..... i have a koyo slim radiator with 2 mishimoto turbo fans attached directly on the radiator.

 

look at it from my perspective....the cooling setup i had before i got the SC, RFS, water/meth, etc...was a mishimoto radiator with the stock fan shroud (that i slimmed down with a zipwheel some because as we know the mishimoto radiator is very large) with the two mishimoto turbo fans barely attached. They were sorta ziptied to the shroud and they had some free movement. although when i got rid of the shroud got a more slim aluminum radiator i have the same turbo fans i had on my last setup but mounted more securely making them more effecient. if anything the setup i had before with the fans and larger core radiator would of gave me cooling problems but it didnt in any way, shape, or form.

i added the SC (which emits more heat into the engine bay) with a better cooling setup than i had before and it randomly overheats when i'm at idle. all day today i didn't over heat once. so im thinking it's not my fans.

but i wasn't at idle for longer than a couple minutes compared to when it over heated from being at idle for a long period of time. but it also overheated from driving at slow speeds with stop and go traffic in high 90 degree weather. then the other time was when i drove it 10-15 minutes, parked for 10 minutes, drove again for a couple minutes and overheated.

it could very well be air entering the system somehow at different times. as soon as i purge my coolant system tomorrow ill see where to go from there.

also those pics aren't very good of the bypass hose. it sorta looks like it's fine but you have to be here to actually see how bad it is.

 

yeah i believe those open up 62 degrees fahrenheit lower than the OEM thermostat.

 

whatever.