Please help me.....

I just got my '86 firebird 305ci and I'm experiencing coolant issues. The radiator had a leak when I got it so I replaced the rad with a new 3 core alloy and now after a drive out it blew a massive hole in the bottom rad pipe.

The temperature hasn't gone above half way but I have noticed a lot of pressure in the system. The oil is clean, and the water doesn't smell at all of fuel.

Any ideas?

 

How are you noticing pressure in the cooling system?

 

I noticed the pipes are rock solid and when the original rad was in the water was escaping with alot more force than I've seen before on a rad leak.

Also when the bottom pipe blew on Sunday it lost all of the water very quickly. To be honest it could just be just weak componets but it just seems to be a bit more than that. Are the coolant systems normally very pressurised on these cars?

Cheers

 

Not more so than other cars/systems, although pressure will increase with higher temps. Normally the rad cap will release pressure into the reservoir first.

Replace the bottom hose and try a new rad cap. The cap should run around $5. Either that or try a pressure test to ensure your existing rad cap is venting.

 

I got a new rad cap with the new alloy rad I fitted, but I will check it. Its starting to look like the head gasket as I have noticed bubbles in the expansion tank while its running. Thanks for your help.

 

Sounds like you may have a blown head gasket. I just purchased an 84 Z28 with an L69 which I believe may also may have a blown head gasket. I get air pressure in the cooling system which bubbles over into the overflow bottle, but only after the engine is shut off. The problem didnt arise on my motor until i drove it for a while. It doesnt do it on short drives so I dont think the leak is that big. Nonetheless, going to pull the heads and do it right.