North American Motoring - R50/R53 Why You Shouldn't Install Silicone Hoses

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- - R50/53 Why You Shouldn't Install Silicone Hoses (https://www.northamericanmotoring.com/forums/r50-r53-hatch-talk-2002-2006/231898-why-you-shouldnt-install-silicone-hoses.html)

Why You Shouldn't Install Silicone Hoses

Hoping to save some MINI owners a hassle with this post. You may see those colorful silicone coolant hoses and think they are an upgrade. I did and bought some. They are advertised as longer lasting than EPDM hoses and, of course, they look nice! But don't get them. Nothing beats the OEM hoses for our MINIs. Here's why:

1. Fitment

This is the big one. A small difference of length and/or angle can be the difference between rubbing on something in the engine bay or not. The Venair set for my R50 was not off by much (see pictures), but it was enough to cause one of the hoses to rub on an alternator bolt, gradually gnawing into the hose. Thankfully I caught it before the bolt rubbed its way entirely through the hose.

The OEM hoses also include lines and markers to make sure you install the angle of the hose correctly. You don't get this with the silicone hoses.

When you buy new OEM hoses, you also get new spring clamps. These clamps are a pain to work with, but they do their job very well, keeping the same clamping pressure on the hoses despite changes in size and temperature. This is not true of the typical worm style clamps. There are special contant-torque clamps which work well, but they are expensive.

2. Water Permeation Rate

Silicone hoses have a much higher water permeation rate than rubber hoses - apparently 10-15 times higher. This means you will lose coolant through the walls of the hoses over time. Not a huge deal if you pop the bonnet to check your fluid levels at every fillup (as you should!), but if you don't check your levels regularly, you could find your temperature gauge shoot up out of nowhere from low coolant levels. Over time, this can also affect your antifreeze-water ratio.

Also, when I had the silicone hoses installed, I would always smell a faint coolant smell after driving. This disappeared after I went back to the stock hoses without touching any other components. I believe this is due to the higher water permeation rate.

3. Durability

Silicone hoses are often advertised as lasting longer than EPDM hoses. Perhaps it might be true, but OEM hoses still last a long time. I did not need to replace mine when I did - it was simply preventative while I had the front end apart. I very likely could have gotten at least another 5 years of reliable service out of my factory hoses (so a total of 10-15 years).

Also, the higher heat that silicone hoses can withstand is really unnecessary. If your MINI's engine ever gets to 375 F or 400 F, the usual high temperature rating of silicone hoses, the hoses would be the least of your worries. EPDM hoses are good up to about 275 F to 300 F, which is plenty.

4. Warranty

Many of the silicone hose kits do not include any warranty at all. The Venair kit did not. The OEM hoses carry 2 year manufacturer warranty. Something to always consider if an issue does pop up...

More pictures. Notice how perfectly the OEM hose fits over the alternator. Not true of the silicone hose.

Thanks for the information!!

Great information. I've never been interested in silicone hoses, but learned a couple of great facts. Never knew about the permeation rate (kind of important, I think). The fact about the spring clamps ability to withstand expansion is something that escaped me, even though now that you point it out, it's rather obvious. I always figured they were used for production reasons. I actually find them easier to work with than worm clamps, using the correct pliers, of course. Mine aren't even really correct for this style, they are the American type, but still work well enough.

Good post...needs to be said.
About 5 years ago i was debating going down the same road....and a post with almost all the same issues about sameco came up....decided right then and there, it was not worth compermising relilibility to make the car look cool....and spend extra $$ doing it!!
Good post!!

Awesome Post gknorr! Never really thought about chaining my hoses, but at least now I wouldn't be getting silicon hoses if I ever do.

Great Information!!! And thanks for the writeup and pics.

Good to know. I'd rather spend money on something that actually does something other than for looks; Specially under the hood.

Very helpful feedback- Thank you for sharing!

Great post. I too will be knocking them off my list of things to do!

My stock rubber hoses are approaching 10 years old and they are in good shape from an outward appearance and feel. The next time I change the coolant I will replace them with OEM hoses, as planned. So 10-15 years for the hoses is not a stretch. But I believe the manufacturer interval on them is 4 years or something silly like that. My coolant's been changed every 4 years or so.

All I can say is thanks. Was shopping for hoses and decided to check the forums and your report came up. Refreshing with OEM hoses now on a 12 year old original car. Thanks

Quote:

Originally Posted by Bernard Barbour (Post 4261509)

All I can say is thanks. Was shopping for hoses and decided to check the forums and your report came up. Refreshing with OEM hoses now on a 12 year old original car. Thanks

Glad it was helpful! You can't go wrong with the OEM hoses.

Unfortunately the MINI doesn't have a big enough demand for quality fitting silicon hoses, there are many platforms out there that the silicon hoses work great for, but being so niche based there isn't much out there that fits like factory.

Even the Samco hoses for the intake of the W11 cars require cutting and modification to be a bolt on part, even though they're only made for one car.

I would think the permeability issue would immediately disqualify silicone as a suitable material for this application.

Hoses are supposed to keep fluids in and other stuff out. Fail.

Short video from Gates on the issue of water permeation:

Its worth mentioning that Gates actually manufactures silicone coolant hoses (see here). For most typical vehicle applications, they recommend you shouldn't use it though.

I've never had good luck with silicone hoses on anything....they ever seem to fit right, and they never seem to last. :no:

Quote:

Originally Posted by IQRaceworks (Post 4261746)

I've never had good luck with silicone hoses on anything....they ever seem to fit right, and they never seem to last. :no:

I've got them on my big turbo TDI build and had them on my last TDI build and Cummins pickup, but once you start running big CFM numbers a multi ply silicon charge tube is worlds better than rubber and far cheaper than V-band clamping the charge piping.

Quote:

Originally Posted by nkfry (Post 4261774)

My experience has been on small stuff like dirt bikes, atv's, and mini's :lol: I can see where they would be better and stronger is some high boost applications.

I found out two years running that rats love the taste or texture of silicone hoses. Think twice if you have to share a garage with these little guys.

Interesting stuff and very informative! Thanks! I never would have spent the $ to outfit mine with all silicone hoses, but have always had that 16 year old me inside thinking, that looks so cool! Lol.
I have one silicone charge pipe to delete the intake muffler on the factory charge pipe. But that will be the only one from now on. I think I would rather spend the $ on something I can feel a difference with. Good info on the spring clamps too! I always figured that they had a good reason for using them, but I never knew what it was. But they definitely hold better that worm screw type clamps! Thanks!