Can I use 3/4" or 5/8" heater hose instead of 18 mm?

Question

I have a '94 Honda VFR and two of the coolant hoses are 18 mm ID.

18 mm is a very unusual ID, and it would be easier to for me to go to the auto parts store and get a size they have in stock, which is 3/4" or 5/8".

Is it at all possible to successfully replace the hoses with a readily available ID?

Old_Fossil · Answer

18 mm is closer to 3/4 inch (roughly 19mm), 5/8 of an inch is closer to 15.5 mm.
1 mm is .03937 inches you can't beat that. Go for the 3/4 inch.

One Answer