Well, yesterday my '87 307 has developed a small radiator leak at the right corner when facing the front of car. All hoses and drain plug are tight, no leaks there. Overflow container is empty, which is not normal for the car. No visible damage like rocks, etc to the front of the radiator. So I went to auto parts store and guy says I need Prestone radiator stop leak product. I pour that into radiator and follow directions on package and drive car and use heater as instructed. Get home and once car cools in garage, I notice the radiator is leaking more now than before I poured in the Prestone stop leak.

So this morning I take rad cap off and the level looks full but the overflow reservoir still empty. The leak has slowed down again. Do you think the Prestone stop leak will work long-term or do you think I need to take the car in to have my mechanic check the rad? I'm wondering if it would be better to have it re-cored or just replace the whole radiator? Have you guys had similar problems with yours?

I'm guessing this is just because the car is now 30 years old and only drive about once every three weeks for 50 miles or so?

Thanks for any info!

 

Ask yourself - how does the "stop leak" know to only plug the leak and not every passageway in the radiator?

"Miracle" liquids rarely work as advertised for any length of time. You have a 30 year old radiator. Get a new one.

 

You can buy a new one or take your current one to a radiator shop for repair.

 

I figured I may need a new radiator but it never hurts to ask! Do I need a copper core or aluminum radiator for this engine? I don't want to buy the best or most expensive radiator. I just want to replace the old one with a comparable new one.

 

Either is fine. I suspect that the least expensive stock replacement you will find will be an aluminum with plastic tanks. Under $100 at RockAuto.

 

Thank you, Joe. Okay that may be the least expensive one, but please let me know the one you recommend for all-around best performance, again keeping in mind I'm not interested in the most expensive or least expensive. I'm looking for your recommendation for a good mid-priced unit, one that you'd be comfortable putting in your own car. Thanks!

 

I've used the equivalent radiator to this one in my 307-powered 84 and 85 full size cars with no issues in daily driving. The next step up would be a brass/copper one. Probably about twice the cost. If that is your choice, I'd probably have the original one recored.

 

Joe, based on the information you've provided, I will go with the aluminum radiator. Thank you, sir.

 

I have the same type radiator on my car. It will take abuse.

 

+1.

... And flush that garbage out of your engine, before it blocks up the heater core or does something else awful.

- Eric