Suspected coolant leak NC700s

[Guest harveydean]

Riding in deluge last week I stopped to get directions, the radiator was steaming and what looked like a lot of hot liquid leaking out.

 

It really was pouring with rain.

 

So - and clearly I'm no mechanic - is it possible that the radiator is leaking.

 

I've been riding the bike since - only short 5 mile journeys - but there's been no indicator lights on saying that it's overheating. Would that be possible (to still ride the bike) if there's no coolant?

 

Or could it just have been loads of rainwater pouring out of the radiator. I know this is a really stupid question - but I really am a numb nuts when it comes to engines.

 

Hoping you can help - the dealer is miles away and just want to make sure I'm not doing any unnecessary trips.

 

Thanks in advance

 

Dean

[Guest mikmcd]

It's quite possible that it was just rainwater steaming off the radiator, especially if you haven't noticed it happening again. 

 

However if you have the manual, pages 76/77 give pretty straightforward instructions for checking and topping up the coolant.

[Guest Whiteyez]

Check your coolant level on reserve tank to see if you have any leak.

 

 

[Guest Mokel]

The radiator will 'catch' a lot of rain when riding into it. I've seen water streaming from mine, along with steam/smell, when I came to stop. I also then checked the coolant level - it was fine.

[Mike5100 2,061]

yeah me too - sounds like water hitting the hot outside and steaming off.

Mike

[Guest jorgegofio]

I've had the same problem in the rain. Just dirty water and grime burning off on the radiator. 

[embee 7,288]

As above, the radiator fins can hold a lot of water, the slope of it means that air flow tends to keep the water in there until you stop and it runs out of the front. It's always surprising after you wash a bike then lift it upright off the stand a whole load of water will dribble out of the radiator fins.

 

As recommended. check the level in the make-up bottle (reservoir) according to the marks, or take the radiator cap off and check that it's full. The radiator and engine side of the system should run essentially full to the top. I suspect yours is OK, but a check is free. NEVER take the radiator cap off when it is hot, it runs at up to 1 Bar positive pressure and can instantly boil if the pressure is removed when really hot. Wait till it's cool.

 

There are effectively a couple of spring loaded valves in the radiator cap which control the pressure for expansion and refill. The make-up bottle works by providing somewhere for the coolant to go when it gets hot and expands and also allows any gases to be purged out of the system, then when it cools down the system will draw coolant back into the radiator to keep it topped up. That's why the hose from the radiator neck goes down below the liquid level in the make-up bottle. If the level in the bottle gets low it can draw air back into the system on cool-down.

Edited November 12, 2013 by embee

[Guest harveydean]

Thank you all for your advice. I've now checked the coolant and it's all good - a torch behind the container is a good way to see the level.

 

It really was pouring that day and as you say, all the water must've been between the fins - a lot of hot water! Released on stopping and the pouring out with the tilt of the bike on the side stand.

 

Really appreciate the advice and has saved an unnecessary trip to the dealers.

 

Thanks all,

 

Dean

[Guest Mokel]

Hey, Murray, really admire the time you take to provide insight to the issues we come across. Huge respect.

[Guest DH1900]

You could also purchase a dye, specific ones exist for automotive coolant. It will colour the coolant a fluorescent hue so any leaks will be obvious. In theory, any dye could be used but you don't want one that decomposes at temperature and clogs your radiator or perishes an element of the cooling system.

[embee 7,288]

A lot of coolants are fluorescent anyway, try a UV light source on it to find out.