Classic Silicone Hoses and OAT Coolant??

[RyCliff]

Following a 'high pressure' situation at Anglesey on Monday I have decided I should probably change my coolant hoses, and I fancy some shiny blue silicone ones  I'm looking at Classic Silicone Hoses as I want to make the change next week and SFS seem to have hit and miss delivery times.

Anyway, Classic Hoses state in their fitting instructions not to use an OAT coolant. The recommended coolant on here seems to be Comma G30, which has OAT additives. Question is has anyone got any experience with these hoses and what coolant have they used? 

Thanks

[StevehS3]

My last 7 had OAT coolant with silicone hoses for about 10 years without problems. I am not recommending anyone uses OAT with them, just stating my experience.

[Jonathan Kay]

Same here.

There's some discussion in the archives, I'll dig it out later. It includes one report of staining.

My Seven has Comma G30 and Classic Silicone hoses, and I'd do the same again.

Jonathan

PS: Members are happy with all three major suppliers of silicone hoses. NB Club discounts.

[Jonathan Kay]

Full search of the archives: https://www.google.com/search?q=site:lotus7.club+silicone+oat.

And thoughts about what might have kicked off the concerns.

As above, that combination is what I use, and there's now a lot of Seven years of exposure accumulated between us all.

Jonathan

[RyCliff]

Thanks both.

Seems to be as I suspected, one person with an issue and it comes up as an issue for everyone.

Cheers Jonathan. I can find one of the discounts - assume the other 2 suppliers are not discounted..?

[Jonathan Kay]

Sorry, I'm not up to date on discounts. Always worth asking? 

Jonathan

[Wrightpayne]

I have a mix caterham and samco branded silicon hoses and the recommended comma coolant and have not had any problems in 10+ years.

When I first fitted the hoses I had an issue with the large diameter ones weeping. This was cured by fitting some better quality jubilee clips with a steel slip liner between the hose and worm drive band. Norma brand IIRC.

Also the J pipe was a challenge (as others have found). I think I took the stat housing out, lubed it and put the hose in boiling water. Worthwhile drilling the stat as helps with bleeding.

Also read up on refilling technique to avoid air locks if you’ve not done it before.

Ian

[Gordon GWF]

I fitted a full set of hoses and new jubilee clips a few weeks ago all supplied by Classic Silicone Hoses and used Comma Xtream G48 antifreeze.

The J pipe was, as expected, a tight fit and I also fitted a bleed T at the top heater hose. After 200 miles all is well with no leaks from any hoses.

[anthony1956]

Also read up on refilling technique to avoid air locks if you’ve not done it before.

I'll say! Just had mega grief with that (K R500). I suspect it was the heater, but don't know. I ended up bleeding the head with a clear 90 cm vertical tube (so I could see the air being ejected) from the head breather on the throttle bodies (and a second on the expansion tank head-to-breather to stop overflows). 

I've used Audi/VW G12/13 etc for years with silicon hoses. (don't know if it has OAT).

Anthony

[RyCliff]

Need to do some reading on the best way to refill avoiding airlocks. No heater installed so I'm hoping that makes things, but I've never replaced the coolant on a car before so should be fun!

[SM25T]

Fill it slowly with the radiator high. If you have a bleed screw on top of the radiator, that will help you get the air out of the highest point.

[Jonathan Kay]

(Crossed with Ian's)

Need to do some reading on the best way to refill avoiding airlocks.

Quick summary of suggested methods and tips. There's lots on each in the archives. Let us know if you can't find what you need.

Jonathan

[ChrisC]

Just for reference, all current Sigma and Duratec cars use coolant with OAT additives.