Coolant Leak Rubber vs Silicone

[Malsprint]

I have been chasing down a coolant leak or leaks. At least 5 of the rubber to metal joints are leaking. I fix one and another starts to leak. I fix that and the previous one leaks again. All of the joints are at the point that they have been over tightened. I think its time to replace all the rubber tubes and give all the joints a good cleaning in the process.

I see that you can get the traditional rubber ones or fancy silicone ones. Even if I get the silicone type I would go for black rather than one of the fancy colours.

Does anybody have any experience with the silicon hoses. Are there any pros and cons between the rubber and the silicone.

[Bumpa]

I've got silicone hoses on my MGB V8 and am very pleased with them. They have been on for at least ten years and are still as good as new. They don't seem to degrade with light or heat, and a V8 MGB engine gets VERY hot. The black is a bit more shiny than the "rubber" hoses but I don't mind that.

[soe8m]

I have been chasing down a coolant leak or leaks. At least 5 of the rubber to metal joints are leaking. I fix one and another starts to leak. I fix that and the previous one leaks again. All of the joints are at the point that they have been over tightened. I think its time to replace all the rubber tubes and give all the joints a good cleaning in the process.

I see that you can get the traditional rubber ones or fancy silicone ones. Even if I get the silicone type I would go for black rather than one of the fancy colours.

Does anybody have any experience with the silicon hoses. Are there any pros and cons between the rubber and the silicone.

Silicon hoses are sturdier than the rubber ones. These have to be tightened more to seal. On modern radiators with nice round plastic tubes these sit ok but on the copper radiators with their copper joints the silicon hoses have to be overtightened to seal. Rubber hoses are softer and will shape to the joints more easily.

The other thing is by moving and vibration silicon hoses are less flexible and will push/pull/twist more on the radiator. Dolomites have average lenght radiator hoses so a lot will be taken by the lenght but copper radiators can get fatique cracks by sturdier silicon hoses.

Jeroen

[cliftyhanger]

Does anybody have any experience with the silicon hoses. Are there any pros and cons between the rubber and the silicone.

All the moulded rubber hoses I have bought for classic cars have been rubbish, breaking down within a few years at best, days at worst.

On my cars I use
(1) new hoses but OEM from modern cars, handy as had a source of free nissan and VW hoses, but he has retired.
(2) new branded hose off the reel. That does last well, no issues at all.
(3) increasingly silicon hoses. Again no issues. The samco branded stuff is tougher than the cheaper ones off ebay, but all are lasting well.

[sprint95m]

Does anybody have any experience with the silicon hoses. Are there any pros and cons between the rubber and the silicone.

Silicone is the way to go, however....

Do NOT buy Silicon.com hoses but instead choose silicone from a UK or EU manufacturer.
Use properly made hose clips, I only use (British made) JCS.




Ian

[geeksteve]

I run silicone on my car without issues. As others have said you should make sure you use a decent quality clamp, not the iffy quality ones with punched holes etc. If you've got any corroded/pitted flanges sometimes they take a bit of extra effort to seal. I'm sure someone here will cringe, but in such situations a quick wipe of Permatex Aviation (the stuff in the white tub with the brush that smells weird and looks like Marmite) works wonders..

Steve

[Malsprint]

I eventually fitted new silicon hoses purchased from Roose Motorsports. I ordered the original finish. I was disappointed when they arrived because they had the Roose Motorsports logo plastered all over them which wasnt the look I was going for. But Roose Motorsport replaced them with no fuss whatsoever even through they had to resend to the US. Excellent customer service.

I am not sure but I think you have the option to select if you want to have the logo or not when you order, and it may well have been my error in not making the correct selection in the first place. If you order these be sure to look out for this.

I also ordered a new radiator with electric fan from them which is very nice indeed.

And so far no leaks. I didnt use any sealant. I figured I would try without first.

[B8WLY]

If it helps I also use the exact same hoses, radiator and electric fan Malsprint refers to from Rouse Motorsport.

So far all I can say is the car is behaving perfectly. No leaks, no overheating issues.

Expensive but worth the money.

Richard.