Changing a Viper rad

**dave6666** · 02-27-2017

The best coolant is the Mopar orange HOAT.

**98RedGTS** · 02-27-2017

Mines green as well but I believe at some point they switched to the orange stuff. Not sure when that was but I think that is what he is talking about.

**Lemay88** · 03-02-2017

Got a price from a local rad shop.
350$ for a re-core of the OEM, (2 core) and 460$ for a 3 core. Sounds like a good price for you guys in the states if you put the exchange rate in.
The core is custom made right here in Montreal, Qc, Canada. The rad shop will put back the original tanks on the new core.
I should get the rad sometime next week, I will post pictures of the re-core job so you can have a idea of the quality of the rad shop.

Ben

**Lemay88** · 03-07-2017

Radiator is back and is going to be installed before the end of the week.
Here's a photo of the finish product. 360$ CND funds. 1 year warranty. New core, original side tanks.
I'll update on how the re-installed went.

Ben
image.jpg

**Lemay88** · 03-09-2017

Rad is back in the car...took about 15 minutes to get it in (fan shroud included).
Now, only need to finish detailing wheel well and wheels, put the car back on the ground, refill with cooling system and wait for May to get here.
By the way, it is confirm, with a minimum of knowledge and knowing your way with a ratchet set, changing a rad on a gen 2 Viper can be done by any shade tree mechanic,
Thanks everyone who gave me tips and get me to do it.

**BrianACR** · 03-09-2017

Thanks for this little write up! I've been thinking of pulling mine and getting it checked out. Now I feel a lot more confident in doing this job on my own.

**Lemay88** · 03-09-2017

Bonjour Brian,

If you can handle a ratchet set, you can do it. Really not much to it.
I was pretty happy I did it.
Feel more confident in trying other jobs.
...and you always have the forum to come to get tips and tricks from the top Viper tech when in need.

Ben

**Dajerseyviper** · 03-10-2017

The viper is actually one of the easiest cars to work on I have ever owned.

**Lemay88** · 03-29-2017

Bonjour Guys,

First time I started the car since I changed the rad.
I filled to pressure bottle and the system, made sure my fasia bottle is half full.
I started the car and let it warm and get to temperature. I got scared at first because the temp gauge went up faster than usual but I remembered that it was probably reading hot air instead of coolant. When the thermostat opened up, temperature went down very fast to normal temp.
Also, when the thermostat opened up, the coolant bottle level dropped so I added coolant to keep it full and closed the bottle after.
Checked the heater hoses and both of them were hot so everything was going great.
I let the temperature gauge go up and listened for the fan to come on, they did and everything seemed fine until I tried squeezing the upper radiator hose...wow, it was hard as hell, like some pressure was build up inside (checked the lower one and it was the same). Turned off the car and pressure in the system went down little bit after.
Now, I am wondering if it is normal. I don't recall ever been like that before and I am wondering what can be wrong.
My little experience tells me it could be 1. Cap on the bottle 2. Little hose from rad to coolant bottle clogged(would be surprising since it emptied the coolant bottle when thermostat opened) 3. normal and system was never full before changing the rad.
I will let the car cool off and try it again, in the mean time, anybody (Dave, the coolant expert, are you there) can help me with that situation.

Thanks again

Ben

**Lemay88** · 03-29-2017

For personnal knowledge...Cap pressure, how important is it to keep it at 17 lbs??
What would happen to the cooling system if I would put a lower pressure cap??

Thanks

**SlowPoke McGee** · 03-29-2017

Originally Posted by Lemay88

For personnal knowledge...Cap pressure, how important is it to keep it at 17 lbs??
What would happen to the cooling system if I would put a lower pressure cap??

Thanks

You would lower the boiling point. Pressure affects boiling point. Just a side note: closed residential boiler systems operating up to 190F are also usually set at around 18 psi.

**SlowPoke McGee** · 03-29-2017

Originally Posted by dave6666

You can't. You have to have a new core made with the 3rd row included.

Here's a pic of an OEM core. You can see the tube sheet has been left blank where the 3rd row could be.

BTW, that radiator core was still good (not leaky) when removed. That mineral deposit buildup is average. Which is why when people take leaky factory radiators out and then rant and rave about how much better the new <insert name of aftermarket brand> radiator cools, I can't help but laugh at how ridiculous those statements are. No, it wasn't your new miracle <insert name of aftermarket brand> radiator, it was the fact that you took out a clogged radiator that didn't flow any more. Any new radiator cools better than an old one. Any. Even OEM.

Well, I've kept my pie hole shut for quite awhile but it's time to address the elephant in the room: that much mineral buildup just ain't normal unless owner (Dave) was using hard tap water. Distilled/demineralized/soft water wouldn't do that.