C2 Radiator Flush

[Jace H.]

I don't want to take my original 67 radiator to the gorillas at the local radiator shop. What is the best flush or cleaning I can do at home?

Thanks,
Jace Holt

[Mike Yager]

Re: C2 Radiator Flush

I use a Prestone flush kit that splices into your heater hose. It works well but is not so good for originality purposes. This is not a concern for me as my car is a driver and the valve is not noticeable.

I use plenty of buckets and a bunch of old empty coolant jugs to minimize the amount of used coolant I put into the environment. Its not really good to just flush it into the street like the old days. Make sure the car's heater is on while flushing.

This works pretty well. After I am done flushing, I open the block plugs to get any remaining used coolant. Refill with 2 gallons of new coolant which will displace a like amount of water in the system through the flush valve.

[Mike Yager]

One other thing

I put a length of hose that you would use for a washing machine drain on the "outlet" fitting of the flush kit. Its a perfect fit and works well with an automotive style hose clamp. Not only does the hose keep old coolant from going all over your car (and driveway) but it also gives you an easy way to fill the jugs and buckets.

Good Luck!

[Terry M.]

Re: C2 Radiator Flush *TL*

I am a fan of a product called RMI-25. It is available only on the web. I use it on vehicles with both aluminum and copper radiators, and it cleans very well. Do a Google search for it by name. YMMV

[Ralph E.]

Re: C2 Radiator Flush

Terry, Do you run the RMI-25 for a period of time through the cooling system and flush it out and replace with new anti freeze or do you suggest leaving the RMI-25 in the system? Reading the RMI-25 web site it sounds like it is just an additive.

[Terry M.]

Re: C2 Radiator Flush *TL*

Their story is that you can leave it in, or use a maintenance dose. I do not do that. I believe the coolant has adequate lubricants, anti-foaming and other chemicals. I just use the RMI-25 as a cleaner every two years. Run it for 500 miles and flush it out, but I do know folks who leave it in all the time with no harm.

[Jace H.]

Re: C2 Radiator Flush = Out Of the Car

I forgot to mention that the radiator is out of the car along with everything else. Should I wait until I get everything back in the car or can I do some flush/cleaning now?

Thanks again,
Jace Holt

[Terry M.]

Re: C2 Radiator Flush = Out Of the Car *TL*

Sorry Jace,
I have no experience with out of car radiator cleaning, short of removing the end tank(s) and rodding the core. That requires the services of a radiator shop which you have ruled out. Perhaps someone else has experience with this issue.
Most, if not all, radiator cleaners require heat to aid their chemical action. I don't know how one would get heat in the radiator with it out of the car.

[Jerry G.]

Re:How about soaking in CRL

I see this lime and deposit removal stuff called CRL. What about closing off one end and filling it up with CRL and letting it work, then do a water flush??

[Clem Z.]

Re:How about soaking in CRL

the deposit in the rad tubes is just part of the problems with old rads. the other problem is that the fins no longer make solid contact with the tubes and you lose heat transfer. that is why if you have a heat problem a new core is the best bet.

[Mike M.]

Re: C2 Radiator Flush

jace: is your 67 a small block or a big block or a l-88. Aluminum harrison's found in mouse and l-88 are pretty particular about chemicals being used in them.Non-L88 big blocks can have end tanks removed and rodded or you can buy new core.mike

[Jace H.]

Re: C2 Radiator Flush

Hi Mike,

My 67 is an L79.

Thanks,
Jace

[Craig S.]

Re: C2 Radiator Flush

And now Tom Dewitt has the complete resto unit...or the correct cores...Craig

[Craig S.]

Re: C2 Radiator Flush

Jace - you may just want to replace it with a new repro from DeWitts. My 67 L79 is not leaking, but it runs hot, so it is coming out and a new DeWitts going in....Craig

[Mike M.]

Re: C2 Radiator Flush

can't say enough about the Dewitt radiators. excellent repro and they cool more than adequatly. mike