New Radiators but hose is diff. size

2 replies to this topic
  • Digger01

Posted July 23, 2012 - 07:11 AM


Hi All,

I just got some new radiators for the 426 and the connections are a little smaller. The hoses going thru the fram is 1/2" but when I hook up the radiator to the motor is is to small 1/2" on the radiators and 5/8" on the motor. Can I just use 1/2" and just stretch it over the water pump connection? can I use/make a adaptor?

do I need to buy new hoses? is there a temporary fix.

Radiators are GPI ordered of that bay site, I selected the wtrac cooling ones and they mounted up nice but the hoses are an issure.

Thanks in advance for any help

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  • corndog

Posted July 23, 2012 - 02:22 PM


If these are Chinese radiators, I've read this before. You could use a 1/2" to 5/8" barb fitting adapter, but I would probably just try to stretch the 1/2" hose onto the 5/8" fitting. I haven't read of any ill side effects with the China radiators (other than this type of fitment), but when your reduce an orifice, you decrease flow and increase pressure. I'm not sure what kind of effect that will have on temperature, but it's worth monitoring with one of the temp stickers. I would proceed with caution, but proceed nonetheless.

  • luckyguy19

Posted August 12, 2012 - 07:05 PM


I rad into this same problem on my 10 YZ450F. I just went down to checker to buy the next size larger coolant hose. Everything went on easy after that. The Radiators look nice and are quite a bit larger than stock.

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