Cooling hose replacement

[Busterwebb]

Advice please. Some of the cooling and heater hoses on my S3 are bulging and I’m thinking of replacing them all before they fail. Are the more expensive silicone hoses worth it? Any recommendations?

[bitsobrits]

I would say no.

The silicone hoses can last pretty much forever. Good quality non silcone hoses can last for decades. So lifespan really isn't an issue with these cars typically doing single digit thousands of miles per year.

Silicone hose typically has a gloss type of finish, often with a wrapped tape looking surface, and for whatever reason the silicone hose folks often like to print their logos on the hose, so the aesthetics are not to all tastes.

I bought a nice silicone set for my S1 E type, but shortly after the install, I replaced the most visible ones (in and out of the header tank) with conventional hose simply for aesthetic reasons as the 'wrapped' surface of the silicone hose didn't look 'period' enough for me. The remaining silicone hoses have remained in place for the 23 years. The regular hose to the header has been replaced once during that time, only for aesthetics, not because they failed.

The one place I would say the silicone hoses really shine is on the lower radiator hose (hose/metal pipe/hose) assembly on the 6 cylinder cars because the silicone is much more flexible and greatly eases this otherwise tricky install. Any location you never want to see/touch again is also a good application.

[Busterwebb]

Many thanks. Really thoughtful and helpful.

[John37]

I've replaced the hoses on my S3. The ones on the car weren't bad but other jobs led me to replacements. I used normal rubber ones. It's not difficult but expect to find other problems. I had to replace the Otter switch T piece, both top steel tubes, both oil cooler connections, both thermostat housings and the steel heater pipe that runs along the sump. Martin Robey sell polished thermostat housings cheaper than others sell the cast ones. I replaced the other parts with stainless steel made by a local exhaust fabricator. I also had my radiator core replaced with an uprated one by a local specialist. The original was well clogged resulting in serious overheating. It ran just below boiling on a motorway trip in January. I flushed the heater and engine block at the same time. Out came a lot of brown sludge. Remove the thermostats if you do this to get plenty of flow.

[Busterwebb]

Thanks and duly noted