New coolant hoses

[JB052]

On our 1700 cross flow engined car after 30 years, the original rubber coolant hoses are starting to crack. Two questions:

1. Are Silicone hoses the best option?
2. Coolant hose kits contain three hoses, top and bottom rad hoses are obvious, but what is the long narrow bore hose for?

[BertBert]

People seem to like silicone hoses, but I've had issues getting them to seal in the past.

I assume the smaller bore host would be for the heater circuit perhaps?

[Drumster]

i've had silicon hoses on mine since 2010 with no leaks. I found that using a bit of rubber lube to put the hoses on helped, but you do need to go round and tighten the clamps after a short while as silicon tends to compress intitially IME

[JB052]

Thanks for the replies,

the additional hose goes from the water pump to a spigot on the inlet manifold so possibly into the cylinder head. No heater fitted in true Colin Chapman style building in lightness.

[BertBert]

That is the heater circuit if you have one. I think that both ends can be blocked off if you don't have a heater