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Radiator / coolant hose seeping leak

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Peppy, Oct 9, 2012.

  1. Hey All,

    (for an '89 Honda CBR250R)

    I've got some coolant seeping out of radiator hoses that connect from the engine to the lower thermostat housing. As best as I can describe, it looks like the coolant is seeping out of the join between the hose and the thermostat housing. I can also see a small patch of rust on the hose clamp. I can't see any split hosing, although it's pretty tight in there, so I'm not 100% sure.

    Given the age of the bike (and therefore probably the hoses) I'm looking for advice on how to take care of the issue. I'd like to get away with just replacing the hose clamp and get back to riding, but I'm just wondering if that is asking for trouble. (I'm concerned that the hoses will be brittle, and I'll either make the leak worse or cut the pipe with the new clamp)

    So, can anyone with some experience with older hoses share their wisdom in how I should be tackling this one?

    All advice appreciated,
  2. the best solution: replace hoses and clamps. depending on the cost of the hoses, maybe $50 plus coolant.

    make sure there isnt a pinhole somewhere that the coolant is coming out of and then running to the joint.
    give the hoses a squeeze, if they feel nice and rubbery, and you are almost able to touch in the middle, they are prob fine. if they feel hard, you are better off replacing them.

    my philosophy on hose clamps: use once or twice, then dispose of. i have had so many hose clamp issues with my cars. spend $5 and get all new hose clamps.
  3. Probably the smart solution, but I'll give 'em a good squeeze before I do just to make sure.
    Any advice regarding sizing of these guys (width, not length)? Are all the hoses bar the overflow tube generally the same size?

    I ask because I've done some googling and found a repco part number for a hose, thought I don't know if there is slight variations between the various hoses that'd make a difference.

    My feeling is I'm probably getting tied up over details that don't really matter, but it'd be good if somebody might confirm.
  4. Usually all the hoses are different lengths/shapes but have the same ID between pairs (to and from the radiator)
    your overflow would prob be a universal straight hose although this doesnt carry any pressure, so isnt as important.

    another thing i just remembered that i have a philosophy about is radiator caps, i make sure i change my radiator cap whenever i change my coolant. these can become faulty and cause too much pressure in your coolant circuit, causing bursts and overheating.

    if you are replacing hoses, take the hoses into your preferred auto shop and say 'i need some of these' they should be able to look up your bike and see if they match, otherwise you may be able to find one that will do the job.

    the amount of times i have gone to an auto store with a drawing and measurements for a rad hose... (i had a different engine hooked up to a stock radiator in a different position :))
  5. Yeah i have the same, weeping pipe at the water pump. Problem is the pipe is so hard to remove that the radiator needs to be unbolted to get the free space.
    Will get around to it though lol.