heater hose expansion

[bumperbozo]

how much do heater hoses expand when they age and harden? I'm trying to replace all my coolant lines (16 years old) and i'm finding it difficult to make an exact comparison because hoses are flexible enough that a little pressure throws off measurement of the diameter, and it appears that the inside diameter may dialate a little as the hose ages? is that correct?

or is it typical to measure the mating spigots?

anyone know what the specs are?

[Bitter]

measure the outer diameter of what the hose goes onto, you want the inner diameter of the hose to be close to that but always smaller.

[bumperbozo]

that's what she said!

[bumperbozo]

but seriously, measuring the OD of the spigot seems the most consistent, but is there a standard for what hose size goes with what spigot size? do i want the hose ID smaller than the spigot, or just that bump on the end of the spigot?

[BLUEMEANIE]

^ Just the bump on the end. The clamp will make the seal.

[bumperbozo]

I think what we need is a standard percentage. the hose ID should be X percent smaller than the end of the spigot. i wonder if gates or any other mfr has a guideline...