I experienced something very strange today. I recently replaced a heater core while finish up the restoration of my chevelle. The carpet is not yet installed and the heater core has not leaked since the new one has been installed. Been in about a month. I took the chevelle out today to shake it down. I installed a new zz4 last October. I really got on it in first gear and once I hit second I noticed fluid running out of the box on the floor pan. I'm puzzled at this. Anyone have suggustions other than a maybe a bad core? Thanks graemlins/angry.gif :confused: :mad:

Did you check the hose clamps going to the heater core at the fire wall?Maybe one was forgotten or not tight enough?I done this once.

You could just have a poor connetion at the heater hose to the nipple on the heater core. Mine leaked there and while you'd think it would run down the firewall on the engine side, it instead pooled in the heater box and eventually on to the passenger side floor.

If you are using original style spring ring clamps they are likely the culprit. Put on some good hose clamps or tighten down the ones you have to see if that doesn't cure the problem.

I have not checked that, but I will. I had that problem with the lower hose when I first installed the core. It could be the top hose. I know you really have to crank on these clamps. They are a pain.

To change the clamps:
You may think about slitting or cutting the hose to remove it from the heater core tube. Pulling the hose off the new core could damage the solder joint between the tube and the core. Hate to see you damage the new heater core.

I had the same symptoms you have... and I also had no carpet. Wouldn't leak unless I was giviner pretty good, above 5000 rpm, then I would see it tricking out onto the pass floor.

In my case it was leaking at the hose connection at the hearer core. I forget which one though... It seems that after installing new hoses, they compressed a bit after they got more use. The clamps were loose, because the hose was kinda squished down under the clamps, and took a set. I just retightened the clamps, and problem solved. I'd check them a couple more times as the hoses get heat cycled and age.

This is the ONLY time for me that any problem has turned out to be something so simple...hehe! :D

chris

Thanks guys. Blub,your suggustion sounds like my problem.