the metal coolant line is that goes over the engine is rusty. do metal coolant lines rust through with age? I thought they were Aluminum? If it fails, will it give me a warning like little pinholes, or does it just go kaput? Anyone replace theirs??

Gotta keep my AAA premium paid up !

 

You mean the pipe that runs from the firewall to the lower radiator?



This is not aluminum, its steel and can rot out. But so can aluminum for that matter. It technically does not rust, but will degrade and breakdown. I've had aluminum thermostat covers that have been eaten through, creating leakage where the top radiator hose attached. Same problem occurs with some rotor housings where they can breakdown around the (water) seal grooves and cause coolant to leak into the combustion chamber.

 

As above, that corrosion is almost always due to someone running straight water for coolant, not mixing antifreeze properly, and / or not changing their coolant on a regular basis. Antifreeze is also able to raise the boiling point of coolant - important in hot climates - and also contains chemicals to control corrosion in the radiator, heater core, and all the metal plumbing tubes that connect them.

Failure mode is pinhole leaks, but once you see those, treat them carefully until you replace them, as a,gentle squeeze will crush the tube and leave you stranded. Note also that the steam nature of hot coolant means you'll notice a low radiator and empty overflow bottle because the pinholes allow steam release which evaporates quickly...

 

5/8" OD pipe will fit the heater hoses. If you have the beehive there's a tee in the pipe behind the engine.

I haven't replaced mine yet but got this aluminum tube because the next engine I'm planning will interfere with one of the OEM pipe bends.
Since my hoses are old I also got new ones and can confirm it fits the 5/8" pipe.

 

yes, that's the tube. the rust is on the outside.

pinholes---->steam (I never would have thought, and I have a bachelor's in Chemical Engineering) Sounds like I will have plenty of warning before failure,

thankyou banzai longduck and tso