Hey all, have been wondering if adding a protective silicone hose over valley hoses makes sense.I know that pretty much every member here has either done these replacements or have it on their short list of things to do. My Jag has been doing really well as of late. Last year I had the typical cooling system problems (thermostat housing, T fitting at octopus hose, radiator hoses, water pump, reservoir tank). My octopus hose looks surprisingly good and the valley hoses (?) seem to be doing their job. However, I am wanting to replace the valley hoses and octopus hose in the not to distant future. I'm sure I will have a reason at some point to deal with the coolant system again (age).

I'm just thinking ahead and wondering if putting larger size silicone hose over the replacement valley hoses makes sense. It appears that the reason these hoses degrade and fail is due to the heat (and age) they're subjected to. So why not surround the new hoses with a larger size silicone hose? I was thinking it should be a good bit bigger than the new hose to allow heat from the hose to dissipate while stopping the extensive heat from the area they're in from cooking the new hoses.

Once I change them I really don't want to have to do it again for many years if possible. Thoughts?

Cheers all, thanks in advance for your input!

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I wrapped them in exhaust heat insulating wrap, the same stuff I used for the EGR pipe. Other members have done similar things following the same by principle.

I have no idea how effective that turns out to be.

 

Makes sense thanks for posting. I thought I read all valley hose threads guess I missed some.

 

My understanding from what happened to one of my lines and others that have posted is that the most common failure is where the line necks down or fits onto the outlet of the flange in the block. (See attached image.)
I am sure wrapping will help some, but I believe that hose is stretched to fit on the fittings, and over time heat cycling, it becomes less flexible and cracks in this area. Same thing happens to all the heater hoses, but the infamous valley hose is so difficult to change. Next time one of mine goes, I hope to hard-plumb it as much as I can and use a high quality silicone hose sections instead of the cheap hose material manufacturers use for all of the formed hoses.