how do Icheck the lid for the radiator

7 replies to this topic
  • per_s

Posted June 16, 2004 - 05:48 AM


I have a problem with the radiator. It is spitting out coolant even if I have a low level in the radiator. It is coming out of the transparent hose connected in the top of the radiator, close to the lid.
I got the tip from a Honda guy to check if the radiator lid was OK or not. Anyone have a tip how to do that on a 426 MY00?
Thanks a lot!!

  • Fly-nBri

Posted June 16, 2004 - 10:39 AM


You'll want to have it pressure tested by someone or you can DIY.

  • per_s

Posted June 16, 2004 - 09:55 PM


And how can I do that?

  • sirthumpalot

Posted June 17, 2004 - 01:55 AM


To test the cap you'll need a pressure tester. They are not cheap, got mine at Napa and you can buy a lifetime supply of radiator caps for you and all of your riding buddies for the price of the tester. Just pick up a new cap and mark it off the list.

Are you moving very slow or sitting still? It might just be overheating, these things do not like to move very slow or sit still, even if you're only idling.

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  • tyzfryan

Posted June 18, 2004 - 09:54 AM


If I try to putt putt around with the kids on even a mildly warm day my 03 450 overheats and spews anti freeze out the overflow

  • DrThumper

Posted June 18, 2004 - 11:10 AM


thats normal, your going slow, you need to keep air going thru the rads. When I stop to wait for my wife I shut it down to prevent this.

  • sirthumpalot

Posted June 18, 2004 - 11:38 AM


If I try to putt putt around with the kids on even a mildly warm day my 03 450 overheats and spews anti freeze out the overflow

DrThumper is correct, these things don't do well going slow. There are quite a few tricks posted on here that can help, such as higher pressure radiator cap, I believe water wetter or some other additive/coolant helps, etc.. Do a search and you can find the tips. Those should help, but in general it sounds like it's overheating from going too slow.

  • Rider_727

Posted June 18, 2004 - 05:11 PM


The best thing you can do is engine ice that stuff is the best. It almost elimates the over flow problem. But if it spews when you rev it up that is a head gasket leak.

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