I have a coolant leak on my ’93 F150 (4.9L, with A/C, about 170,000 miles). I’m going through a decent amount of coolant – probably every 10 days I’ll find my coolant reservoir empty. I believe the leak is at the point on my radiator where the metal core is crimped to the plastic sides. This area on the radiator, and nearby areas of the engine compartment appear to be getting wet. However I have not been able to see an actual leak, even with the engine warm and running. The “pan” underneath the radiator (way down low, angled with a kind of trough – is this the “air dam?”) always has a puddle of coolant sitting in it.

My Dad suggested that I try some radiator stop leak, but after reading a few posts I’m now worried that I could end up blocking my heater core or other internal passages. I’ve priced out a new radiator, and while it’s cheaper than I had expected it’s still not really (financially) an option for me at the moment.

So what should I do? Try some stop leak and see if that cures it? (and if so, are there any brands in particular that I should look for?) Or should I just keep adding coolant and do nothing else for now? I read that there is an ultraviolet dye you can add to coolant to detect leaks – is this something I should try? And finally, if I do end up replacing the radiator, how big a job is that?

Thanks!

 

sounds like you have a cold water leak.you need to pressure up the radiator and see where it leaks at.i tryed black pepper on mine it worked for a while then i finnally installed a larger radiator.pepper wont hurt its easy to flush out.

 

This is a common leak for the radiator. The head is held on by crimping the core "Fingers" around the head flange. These can leak when they are cold and then stop when the engine warms up. There is basically nothing you can do to fix it. I don't recommend any type of stop leak - if you have to wait to replace the radiator - I would just keep adding coolant as needed. On the down side, If you have pets - keep them away from any coolant on the ground - gylcol is very toxic and for some reason dogs love to lap it up off the ground - stupid S***'s.

 

After doing a coolant flush on a 01 Grand Am (with the T-stat under the engine) I can tell you why animals like the coolant--it does taste sweet, nothing great but sweet none the less.

 

Most parts stores sell powdered aluminum in a small container. This works well to plug the leak and flushes out easily enough and lasts longer than pepper ( or raw eggs which I once used in an emergency)

 

It is the radiator side tank rubber gaskets. I just posted on another thread about the same thing. The heat of the coolant will dry the water off the plastic side tank so that you don't think that is where the leak is. Mine keeps the little area under the radiator wet.

There is a stop leak called DIKE that you can buy at Freightliner truck dealers that will stop the leak, and absloutely not clog up the cooling system. I have used this product on all types of engines for many years with great results.

I have a can now, and I am waiting for the radiator to get low enough on water to put some DIKE in it.

 

I've used bars leak in my radiator before. Never had a problem with it clogging the system. If you do use some add a small amount and run the engine to circulate it through. See if that stops the leak.

 

I just pulled my radiator out an took it to a radiator shop today. It would just leak out all the time so I couldn't even run the truck. He said the plastic bucket on the side had to be replaced. The whole job only cost 80.00 so I'm happy. It seems that if you take it out yourself and get it fixed you would save yourself a lot of trouble with water pumps, thermostats, heater core as well as the radiator itself. I wouldn't use any stop leaks.

 

I have never found a shop that would try to fix one the radiators with an alum core. The heads are held on by bending "fingers" on the core around the flange of the head. I have been told several times that these are not repairable. Are you sure they didn't give you a replacement? If so, $80 is a very good price.

 

The radiator is definitely the same one. I have it back in the truck and it is working great. No leaks! I didn't even pay attention when I brought it in that it had plastic sides. I could tell which side was replaced though due to the fact it must have been after market. It didn't quite fit perfect. The screw hole was a little to high because the support was a little lower. I am definitely happy.

 

Iv'e had VERY good luck with fixing leaks with epoxy putty. I wouldn't think of going on a long trip with out it! Just jam the mixed putty where ever it leaks after the pressure goes down wait 15min. then drive away! Iv'e had 'em fixed that way for YEARS!!