czarredd

So it appears my radiator is rusted out inside and I need to replace it. Noticed temp rising more than usual and when I went to inspect....brown liquid (rust) had spewed out of radiator cap onto the engine. I've priced a stock radiator at $100 but was told that I should look into the Engineered Cooling Product radiator. The aftermarket is nice and is a 2-row but is it really worth the extra $150 or so....or is stock good enough? Thanks

blue94

If it is not leaking or clogged up I would say it probably needs a good flush. The radiator has nothing that will rust, alum and plastic so the rust is coming from somewhere else (block, heads, water pump). Rust in its self will cause temp to go up.

If the radiator is bad and the stock one worked well I see no need.

czarredd

Ok thanks. I believe the radiator may indeed be clogged...causing the back-up and rusty spew out. Does that sound likely?

Goldcylon

Unless you have modified your engine, like stroked it, done major head work etc. a 2 row OEM factory replacement is good enough. Over time the plastic ends tend to swell on these radiators anyway and the C4 is a well known nose vacuum that sucks in all types of road debris, like leaves, plastic bags and dirt, sand and silt that's builds up in between the cooling fins. I would suggest at a minimum to flush the radiator and pull it to hose off all the debris and clean off the front of the radiator as much as possible if money is tight. Since the radiator is already X years old I would suggest replacing it with the OEM replacement option, clean out the radiator bay area and load in plenty of new green stuff

blue94

It is a pressurized system so unless the car sat and cooled down that could be normal.

czarredd

Great thanks! Should I be worried about any the gunk that I'm seeing in radiator cap being in the engine? Will a complete flush handle that as well? Thanks so much.

Goldcylon

If all you are seeing is gunk and rusty water then yes you should be a little concerned and a flush should take care of your problem. However the cooling issue still might be debris in front of the radiator blocking efficient airflow. You have a couple of areas to look into. Refill with 50% green coolant and 50% distilled water after cleaning. I suggest while you are there take your radiator cap to the auto parts store and have them do a leak test on it as well.

czarredd

Thanks!

antfarmer2

Make sure you back flush the heater core to make sure it is not clogged there and pull your knock sensor (s) you will be surprise how much crap will be in there. Turn your head and keep your mouth closed.

Christi@n

Recently mine cracked. Replaced with OEM acdelco with plastic side tank for about 150$, at the moment work pretty well, when cruising temp is 180-190 F.

desertmike1

The one thing you don't want to do for sure; is throw a brand new radiator in a dirty cooling system.

aklim

You need him to turn his head and cough too? Oh wait. Different test. Why do you keep spoiling the fun. I had to learn the hard way so let him learn what not to do.

aklim

Before I reinstall, I would take a garden hose, less the golf ball and send water through both the ports in the lower block. You'd have to take the Knock sensor off and there is another port that sends coolant to the oil cooler that has to come off too. Flush, drain, repeat until the thing comes out clean and then flush once more.

czarredd

So after lots or reading and you guys awesome wisdom.....I'm going to attempt a full super flush myself. My only concern is jacking car up and using jack stands....I've always been a little leary about there safety. Any alternatives to jack stands besides going to the shop and getting the corvette tax?

aklim

I'm not sure how you would get the block level unless you put 4 jack stands otherwise if you flush it, the crud slips to the back of the block. I haven't had too many issues with the Corvette tax since I shop around and make sure that the book times are what they say they are or I walk.

I think a lot of shops that don't want to work on a car just simply tack a ridiculous number to get rid of the customer.

czarredd

Thanks...gonna do some serious shopping around!

aklim

BTW, check that your fans are operating right. I found that in stop and go traffic and 85 outside, the temp was approaching 240 or so. Thought that wasn't right with the DeWitts radiator so I checked the fans. Apparently the relay holder was not put in properly and the relays were not connected. Connected them and now the temps are midway in stop and go traffic. Must have been left out the last time the cowl was taken off for inspection and cleaning by the mechanic.

I'd fire the mechanic but since it is me, I'd give him a pass.