New motor running way to hot in 95 cobra

[walker95svt]

It's kind of a long story.... This motor has been trouble from the beginning for way more than just this. I know new motors and modified (especially stroked) motors place more of a demand on your cooling system, but mine is almost undriveable. With the old motor, it never got hotter than 180 degrees, or the "OR" area. Now, it goes past the "M" and occasionally the "A" of "NORMAL" on the stock gauge. The fan does not appear to come on until after the "M" is almost passed. I have tried getting it to boil over, as it does not want to and there appears to be air in the cooling system. The upper radiator hose, when pulled, reveals coolant recessed into the thermostat, like it's not getting around. I installed a 180 degree thermostat to help combat this new motor's propensity to get hot, but it's having little to no effect. It does keep the temp from exceeding the "A" anymore. The water wetter I poured in looks to have little effect as well. I could swear my fan came on sooner with the stock cobra motor. I realize I should modify my cooling system, but it should be at least driveable, right? Anybody with any manner of experience, suggestions or comments would be greatly appreciated!! Anybody know how to decode the stock gauge?


here's the short list: CHP pro street all forged 331, AFR 185s, Comp blower cam, 7 quart kicked out sump pan w/ higher volume pump, stock cobra upper and lower intake with spacer, 65mm TB, new water pump, stock oil cooler, and I don't know what else might make a difference....but that's the short list.

 

[S/CBlack95GT]

Well for one you need a real gauge to see what temp it is actually running at. To make sure all the air is out remove the radiator cap and allow the engine to run. The coolant will start to overflow and possibly bubble as the air is released.

Continue to run the engine for several minutes after the thermostat has opened and until the air stops coming out. This process makes a big mess but it will remove the air.

 

[RIO5.0]

Sure its not burped properly...I had a mofo of a time to get mine to come around....Pull the intake sensor and take a look see....maybe even top it off from there a few times...
Is it sucking the resevoir dry so to say??? Keep topping that off to help burp it..
I agree on the gage, you need a real one... ...a motor like yours and you know she's gonna run a tad hotter...
Next time you see it in the hot zone just pop your heater fan on...this will kick the fan on and you should see...maybe the stock gage move....With my AM gage its get to 210 or so at a stop sign...i click the heater in the midway position so I don't get baked out...usually on the 2nd setting and within 3 minutes or so it drops 10 degree's easy...Its kinda homey...but it may be worth a try...It'll least tell you if the fans are kicking on....

 

[walker95svt]

Well, I've ran it a few times to the point of near OVERheating it with the radiator cap off, and it never boiled over, or burped. It is sucking it dry little by little, I guess that's a sign of SOME air getting out...... I've tried turning on the heater to suck some heat off the engine and it actually makes it hotter; go figure. This car doesn't want to make sense. Anybody know somewhere I can get a fan with an adjustable turn on temp for a 95? as usual, it's always for 79-93s. I'm sure someone makes a radiator/fan upgrade package for our cars, I just haven't found them as of yet.

 

[ponyboy19]

Are you sure the head gaskets are possitioned correctly with the word "front" towards the front of the block.. If not it will cause major overheating problems.

 

[LoudToy958]

Someone beat me to the head gasket question. Good call. Could cause a lot of flow problems(even blockage) if they are installed incorrectly.

The gauge in the car is very inaccurate. As much as 30 degrees to be honest. My factory gauge is never consistant. My AM reads between 180-185 all the time, and the Factory is sometimes on the N, and others on the R. It's very useless. No better than a light IMO. Spend the 40 bucks for a temp gauge, and you may find that your temp is right on.

Another trick, drill two small holes in your t-stat. One on each side. This will let a small amount of coolant flow through and this aids in bleeding the cooling system of built up air pockets.

As far as turning the fan on at a different temp, you can do a manual switch, or buy a chip. I have a superchip, it kicks the fan on around 184*. Works wonders for cooling. The fan is on a lot, but the car stays cool. I would rather pay 100 bucks for a new fan every year than pay for a overheated engine. (Not that the fan has ever gone out) You get the point.

I see you are still running the stock oil cooler, that is good for about 12*+ believe it or not. Cars without them tend to get hot faster, and stay that way longer.

I would deffinetly look into a custom chip, a Anderson PMS, or something of that nature. All of which will allow you to control you fan on and off settings. Hope you get it figured out.

 

[walker95svt]

It's possible but not likely with the head gaskets. I originally had SEC copper race gaskets (the motor is built for boost) to lower my compression a little more and O-ring it all, but they were found to be not sealing right as we were about to crank it all up. I deployed days after this, and the same friend of mine that helped me build the motor swapped the gaskets and flushed the oil while I was overseas. I doubt he put them on backwards, but that sounds like it could cause all of the above problems I've had. Lets hope it's just needing a good burp. The level in the coolant does keep going down with none in the overflow, oil, and none on the ground....... What's an anderson PMS?

 

[95CobraMike]

pms= programable engine management system

you can adjust all sorts of aspects of your car from inside.. a/f ratio, timing and all that stuff.. its like a self tuning device (meaning you can somewhat tune your own car) i've heard good things about them

 

[final5-0]

I've been through some of the same kind of higher temps stuff with my car as the combos have changed over the years.

First thing is......more power means more heat has to be dissipated

When I was stock, temps were ok ...... even in Texas summers

Ported E7s and a few mods ...... temps went up but very little

Current combo ...... temps went up big time

As for the stock temp gauge ...... I know it is not accurate but it seems to me that it it should give the same reference no matter what combo you got.

My solution for the higher temps was to turn the fans on at lower temps and use a Fulidyne & Stewart wp.

My stock gauge now ranges bewteen 1/3 & 1/2 in the summer and in the winter it ranges between the mark and the N.

Later
Grady

 

[1EVIL88VERT]

i think its time to pull the t-stat back out and drill a little hole in it, i did that to mine and it works....just one little 1/8in. hole and make sure its at the top of the t-stat...