Thermostat question - Fiat Scudo

[Whitespirit66]

I'm going to flush my cooling system on Fiat Scudo 2.0jtd van (2004) at the weekend. I have no experience of modern thermostats, and I believe the stat on this van has a rubber seal that fits around the edge of the actual stat.

Does this rubber ring seal also form the seal between the stat housing cover and the block, or will I need a paper gasket to do this?

Also, does anyone know if the rad is likely to have a bleed plug at the top? There's one on the stat cover, but not sure about the rad itself. The coolant reservoir is the highest part of the system, so I don't suppose there should be much problem with air if I leave the cap off with engine running after refilling.

Another thing - the coolant in at present is red. Will the Scudo be OK with blue, as I have lots of that in the garage?

Thanks for any advice.

 

[Burnerman]

I've never known a thermostat with its own seal require another gasket, but obviously when you unbolt the thing all should come clear. I am fond of smearing a bit of blue Hylomar around the rubber though, just to help things along.
Regarding the coolant - blue stuff usually has a life of 2 years, and the red stuff 5 years......however some manufacturers use their own formulas which may be yellow or green, for example.
Its best not to mix the stuff, and bear in mind its not the antifreezing qualities that disperse, its the corrosion inhibitors......if your stuff is ancient then I'd go for a new mix such as Comma.
The radiator probably doesn't have a bleed screw at the top side - the common places are the thermostat housing and the top heater hose.
Just run the engine up to temperature, adding coolant as necessary as you go.
John

 

[Whitespirit66]

Thanks for your reply John.

Just watched a Youtube video for changing the same type of stat with rubber seal around the edge of stat. He didn't use anything else to seal it - so will whip mine off and see.

Which Comma product do you recommend I use? Should I just bung some Fernox in?

Will have a look for any other bleed points, but as said the reservoir is approx. 6" higher than everything else so shouldn't be a problem.

 

[Burnerman]

At the end of the day, there are two types of coolant....the most recent one is the OAT type (Organic Acid Technology) and this superceded the ethylene glycol type.
Every manufacturer I've come across now uses the OAT formula (probably because its more eco friendly than anything else).......both types have a life of 5 years, and they shouldn't be mixed.
I tend to use the Carplan Red formula - its as good as anything (apart from Fernox )
Regarding the bleeding - do keep an eye on the level as the engine warms and feel for the hoses getting hot......once the thermostat opens the radiator will surge with heat.
Check the heater too - if this goes cool, thats the first sign of an air lock or low coolant levels.
Be lucky!
John

 

[Whitespirit66]

Ok thanks John. Will give it a go.