Coolant

[markaluge]

I am getting close to the moment of starting the car for the first time in 4 years and so had better put some coolant in her. The system was fully drained and I have fitted an upgraded water pump and new hoses. 
so the question is: what is the recommended coolant to use please?

Cheers, Mark

[John Morrison]

I use 25% Blue antifreeze and change it every 2/3 years.

John.

[Motorsport Mickey]

+1 with John. The act of flushing the anti freeze and renewing every 2-3 years removes sludge and contaminants from the engine block.

When these engines were new they were run with plain water (better cooling), and only had antifreeze added for winter. (not as good as current antifreezes).

This was flushed out and dumped at the end of spring and replaced with fresh water only again. This goes a long way with keeping the waterways clear and capable of engine cooling. The modern antifreeze is capable of lasting the 2-3 years and retaining the anti freeze characteristics, but a flushout with plain water still helps remove the sludge which accumulates within the engine waterways. Otherwise you'll find the small block drain under the exhaust headers will block solid.

Mick Richards 

[ctc77965o]

I suggest run on water to start with, just in case there's some internal leak. Once the engine has been though a few heat/cool cycles without leaks, then drain off some of the water & add your corrosion protection and antifreeze.
Reason for this is that if you had some big leak and the coolant & oil mix, then a high glycol coolant will strip the oil film off journals and bearings and risk fast damage to the bearings. Whereas pure water will not have this stripping effect, even if there's water in the oil, the oil film on the bearing surfaces will survive for a while and provide protection. Once the leak is fixed and the contaminated liquids drained off, new oil can be added and any residual water will just boil off in first significant heat cycle.

Also, if you've got an external leak that only shows-up as things warm-up, it saves having half your precious glycol dumped on the garage floor.

[Lebro]

I use 50% EG antifreeze, change every 2-3 years. The higher concentration gives better corrosion resistance, & I have not had any overheating problems.

I am running a re-cored radiator (original) with the starting handle hole removed. When ever I drain the rad (as I have done recently for other reasons) the coolant comes out as clear as when I put it in.

Bob

[Rod1883]

As per Bob, although probably more 30 to 40% EG, plus I use water collected from my dehumidifiers rather than that from the tap in our hard water area.

[trchris]

I’m with Bob 50% bluecol, change every 3 years

Chris

[stuart]

1 hour ago, ctc77965o said:

I suggest run on water to start with, just in case there's some internal leak. Once the engine has been though a few heat/cool cycles without leaks, then drain off some of the water & add your corrosion protection and antifreeze.
Reason for this is that if you had some big leak and the coolant & oil mix, then a high glycol coolant will strip the oil film off journals and bearings and risk fast damage to the bearings. Whereas pure water will not have this stripping effect, even if there's water in the oil, the oil film on the bearing surfaces will survive for a while and provide protection. Once the leak is fixed and the contaminated liquids drained off, new oil can be added and any residual water will just boil off in first significant heat cycle.

Also, if you've got an external leak that only shows-up as things warm-up, it saves having half your precious glycol dumped on the garage floor.

This is the best way to start with on a fresh build just in case of leaks/problems etc.

Stuart.

[markaluge]

Many thanks all, some great advice there.  I will collect the water from the dehumidifier too. 

Mark

[Lebro]

Oh yes, forgot to say I use rainwater.

Bob