Changing coolant

5 replies to this topic
  • JBM

Posted December 18, 2000 - 08:56 AM


When changing the coolant in the 426, is what the manual says all I need to do. It seems really straight forward. Any tips or hints? How do I flush out the system before putting in the new stuff?

  • SUnruh

Posted December 18, 2000 - 10:52 PM


only use Distilled water. NOT tap water or even bottled water. has to much minerals in it. you'll get calcium build up and that will increase operating temps and then problems start happening fast.

  • Hick

Posted December 18, 2000 - 11:03 AM


I don’t recall what the manual says exactly, but if you just remove the drain bolt 99% of the coolant will come out. There may be a small pocket or two in the bottom of the rad. tanks but that’s it. Remove the cap to ensure a steady stream out the drain hole, its easier to catch it all this way.

All the water passages in my 426 looked perfect after about 60+ hours so I’m not sure flushing is necessary, but I’ve always been careful to use 100% distilled water mixed with coolant.

I have replaced my impeller shaft, it was letting coolant by where the seal had worn a small groove in it. If you’re especially anal you may want to check this, or you can just wait until it leaks like I did :)

There are two seals on the shaft, one on the water side and one on the oil side. If water gets past the first seal there is an internal passage in the cases between the two seals that will allow the water to escape, I suppose to prevent it from contaminating the engine oil. The passage exits the cases below the water pump and is about 1 mm in diameter and this is where coolant will exit if coolant is getting by the pump seal.

Hope this helps! (?)

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  • smitty33

Posted December 18, 2000 - 11:42 AM



SUnruh has the right idea about not using tap water but...

"Distilled water still has minerals and chemicals in it, that's why you should use Deionized (Di) Water. It is a more pure form of water."

Thats strait from Dave at Engine Ice, and he knows Cooling systems!

Hope this helps


Hold it Wide...

[This message has been edited by smitty33 (edited 12-18-2000).]

  • JBM

Posted December 18, 2000 - 12:23 PM


Thanks guys,
I just wasn't sure if all the coolant came out with the drain bolt or not. I've already purchased Maxima Coolanol, which is anitfreeze premixed with deionized water, just to be safe. I figure once a year for new coolant.
Hey Hick are you ever gonna make it to Socorro for some riding?

  • Hick

Posted December 18, 2000 - 01:51 PM


Originally posted by JBM:
Hey Hick are you ever gonna make it to Socorro for some riding?

I don’t know when, I’ve been busy every weekend helping my dad out on the ranch and of course now that I’m an employed Hick weekdays are out as well. I haven’t ridden much at all lately (horses don’t count, but they do make you’re a$$ monkey-butt proof :) ).

Since pop is in T or C and I’m just outside of El Paso I may split the diff, help him out one day and ride up in Socorro the next. I sure do love that big, long sand wash…

If I plan this out I’ll post or send an email. It would be great to hook up with a local, I’d love to do some scouting to help my results in the next race there.

So keep an eye out for me.

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