Evans Coolant question

**johngoodman** · 02-22-2010, 07:07 AM

I'm thinking about using Evans NPG+ in a new LS1 engine. I'm familiar with all the positive points, but would like to hear what others think. Also, I would appreciate any tips on how to get all the water out of the system (it's been run once with water). Suggestions on a zero pressure radiator cap would also help - a special cap or just remove the seal on the existing one?
John

**pajeff02** · 02-22-2010, 08:16 AM

The engine has two (2) block drains -- the left one is a large brass plug located on the side of the block towards the front and requires a 17mm allen head socket to remove. The right one is quite a bit smaller and is located above the starter, parallel to the ground, and a 5/16" allen head socket fit nice and tight (it is probably a metric fitting).

Do not know anything about the Evans coolant. Why would you run the system at zero pressure? That will lower your boiling point.

**Firebirdjones** · 02-22-2010, 08:25 AM

I've seen and read alot about the Evans coolant. Everyone rants and raves about it. Haven't actually had any experience with it though, and don't really plan to.

I can tell you it's hella expensive though. I'll stick to the regular stuff with routine flushes. Worked for me for 30 years, I see no reason to change now.

I too am confused at the zero pressure cap, don't remember any mention of that when the Evans coolant was tested.

Let us know how it turns out for ya.

**johngoodman** · 02-22-2010, 09:19 AM

Thanks for the tip on the two plugs - I knew about the brass one but the one above the starter I didn't.

As far as the questions about Evans Coolant, here is what I've read:
It won't boil until almost 400 degrees, so no pressure is required.
No pressure means no blown hoses.
It won't freeze until -40 degrees, and doesn't expand when it does.
It contains NO water, so vapor, cavitation, and steam don't exist.
It does contain some glycol, but it is chemically neutralized & not-toxic.
It's a little more viscous than water so it flows a tad slower.
This means slightly higher coolant temps but well within operating range.
It won't corrode, so there is no need to flush it out.
It is the recommended coolant for all Rotax engines in airplanes.

One question on the drain plugs - are they torqued? To what?

John

**pajeff02** · 02-22-2010, 10:02 AM

Originally Posted by johngoodman

One question on the drain plugs - are they torqued? To what?

John

I would need my service manual to tell you the torque. Quite honestly, I applied a bit of blue thread sealant paste and just tightened them snug on our car.

**johngoodman** · 02-25-2010, 04:19 AM

Thanks for the tip on the two drain plugs. The large brass one is, indeed, a 17mm. The one behind the starter is 8mm.

I e-mailed the Evans folks and they got right back to me - They told me not to worry about the pressure cap since the Coolant won't produce any vapor. The only pressure created is by the water pump. So, they said to just use the stock radiator cap. The hoses shouldn't blow because the only pressure in the system is water pump pressure.
John