2004 EX250 Leaking Coolant After Change

drc84 · April 12th, 2014, 11:00 AM

Hello everyone!

A few weeks ago, I changed the coolant in my 2004 EX 250. I used the guide featured on faq.ninja250.org.

When I finished changing it, I didn't notice the fluid leaking. However, as soon as the next day of driving to work, when I'd arrive at work or arrive back home, the bike would slowly leak coolant, as featured in this video:

https://www.youtube.com/watch?v=bhsA..._KvnsbKWPfByBA

As you can see, it doesn't leak much. It's been doing this since I changed the coolant, and I guess it hasn't run out of coolant yet. I checked the bolts that I loosened to change it and they all seem to be tight.

What should I do?

Thanks for taking the time to read this, and for any help you can give me!

Motofool · April 12th, 2014, 06:01 PM

You need to solve that problem as soon as possible !!!

A lack of coolant around the cylinder head can be catastrophic for these engines.

It seems to be coming from the drain plug or from a crack in the body of the pump or connectors to the hose.

The high pressure in the system makes it leak more when hot.

Ninjinsky · April 12th, 2014, 06:18 PM

One thing I had recently was coolant dripping there. It's the water pump and there's 2 'o' ringed pipes, the drain plug and the gasket. So natch you assume that is where the leak must be.
I went through them all, draining and refitting refitting twice! Still leaking

Turned out the leak was at 'O' ring on the main union that goes into the top of cylinder head.
It trickles right down the back of the engine, across to the left and down over the water pump
Fooled me completely

Motofool · April 12th, 2014, 06:22 PM

Quote:

Originally Posted by Ninjinsky

..........
Turned out the leak was at 'O' ring on the main union that goes into the top of cylinder head.
It trickles right down the back of the engine, across to the left and down over the water pump
Fooled me completely

http://faq.ninja250.org/wiki/Hints_%...g_coolant_pipe

drc84 · April 19th, 2014, 02:21 PM

Okay, everyone. Thanks for the quick and informative replies! I haven't been able to figure out where the leak is coming from yet, but I did notice that the amount of coolant that leaks out each day has slowed down considerably.

Today, I got the chance to get out there with the bottle of coolant and refill it. I was expecting to refill it nearly the whole way; however, it only took a little bit of coolant before it was full again.

The reserve tank under my side panel was empty, so I refilled it all the way.

Why did it seem like so much had leaked out? Any ideas?

Ninjinsky · April 19th, 2014, 02:53 PM

Hi DRC84. Just pointing out that under the side panel is the 'expansion' tank not a 'reserve' tank. As the engine heats up the level will go up then, as the engine cools down, coolant is drawn back into the engine so you will see levels fall. It will fluctuate over a range of maybe 1/2 inch between cold engine in winter and hot engine in summer. The key when checking for leakage is to always compare levels in the same conditions.

quarterliter · April 20th, 2014, 09:19 AM

Quote:

Originally Posted by Ninjinsky

One thing I had recently was coolant dripping there. It's the water pump and there's 2 'o' ringed pipes, the drain plug and the gasket. So natch you assume that is where the leak must be.
I went through them all, draining and refitting refitting twice! Still leaking

Turned out the leak was at 'O' ring on the main union that goes into the top of cylinder head.
It trickles right down the back of the engine, across to the left and down over the water pump
Fooled me completely

I'm having that exact same issue.

drc84 · May 21st, 2014, 01:11 PM

I'm bumping this with a video:

Link to original page on YouTube.

This is getting worse and I think it's going to cause a problem soon. Anyone have a recommendation of a guide to use to diagnose the problem or something?

DaBlue1 · May 21st, 2014, 02:32 PM

Quote:

Originally Posted by drc84

This is getting worse and I think it's going to cause a problem soon. Anyone have a recommendation of a guide to use to diagnose the problem or something?

You will need to take the fairing off so you can see exactly where the leak is. If coolant is leaking from the top of the engine, it is most likely leaking from the coolant pipe attached to the head (just above the carbs). There is an o-ring that seals the connection.

If it is leaking below and all the bolts are tight it's either leaking at the water pump gasket or the coolant pipe o-ring

alex.s · May 21st, 2014, 03:11 PM

replace the crush washers on the coolant drain plugs?

April 12th, 2014, 11:00 AM	#1
drc84 ninjette.org member Name: Ralph Location: Baton Rouge, LA Join Date: Jun 2013 Motorcycle(s): 2004 EX250 Posts: 12	2004 EX250 Leaking Coolant After Change Hello everyone! A few weeks ago, I changed the coolant in my 2004 EX 250. I used the guide featured on faq.ninja250.org. When I finished changing it, I didn't notice the fluid leaking. However, as soon as the next day of driving to work, when I'd arrive at work or arrive back home, the bike would slowly leak coolant, as featured in this video: https://www.youtube.com/watch?v=bhsA..._KvnsbKWPfByBA As you can see, it doesn't leak much. It's been doing this since I changed the coolant, and I guess it hasn't run out of coolant yet. I checked the bolts that I loosened to change it and they all seem to be tight. What should I do? Thanks for taking the time to read this, and for any help you can give me!

April 12th, 2014, 06:01 PM	#2
Motofool Daily Ninjette rider Name: Hernan Location: Florida Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot. MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16	You need to solve that problem as soon as possible !!! A lack of coolant around the cylinder head can be catastrophic for these engines. It seems to be coming from the drain plug or from a crack in the body of the pump or connectors to the hose. The high pressure in the system makes it leak more when hot. __________________________________________________ *Motofool* *.................................Never ride faster than your guardian angel can fly* "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí

April 12th, 2014, 06:18 PM	#3
Ninjinsky ninjette.org certified postwhore Name: Paul Location: UK Join Date: Apr 2014 Motorcycle(s): Ninja 250, Yamaha RS200 (classic) Posts: A lot.	One thing I had recently was coolant dripping there. It's the water pump and there's 2 'o' ringed pipes, the drain plug and the gasket. So natch you assume that is where the leak must be. I went through them all, draining and refitting refitting twice! Still leaking Turned out the leak was at 'O' ring on the main union that goes into the top of cylinder head. It trickles right down the back of the engine, across to the left and down over the water pump Fooled me completely
	1 out of 1 members found this post helpful.

May 21st, 2014, 03:11 PM	#10
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	replace the crush washers on the coolant drain plugs? __________________________________________________

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April 19th, 2014, 02:21 PM	#5
drc84 ninjette.org member Name: Ralph Location: Baton Rouge, LA Join Date: Jun 2013 Motorcycle(s): 2004 EX250 Posts: 12	Okay, everyone. Thanks for the quick and informative replies! I haven't been able to figure out where the leak is coming from yet, but I did notice that the amount of coolant that leaks out each day has slowed down considerably. Today, I got the chance to get out there with the bottle of coolant and refill it. I was expecting to refill it nearly the whole way; however, it only took a little bit of coolant before it was full again. The reserve tank under my side panel was empty, so I refilled it all the way. Why did it seem like so much had leaked out? Any ideas?

April 19th, 2014, 02:53 PM	#6
Ninjinsky ninjette.org certified postwhore Name: Paul Location: UK Join Date: Apr 2014 Motorcycle(s): Ninja 250, Yamaha RS200 (classic) Posts: A lot.	Hi DRC84. Just pointing out that under the side panel is the 'expansion' tank not a 'reserve' tank. As the engine heats up the level will go up then, as the engine cools down, coolant is drawn back into the engine so you will see levels fall. It will fluctuate over a range of maybe 1/2 inch between cold engine in winter and hot engine in summer. The key when checking for leakage is to always compare levels in the same conditions.

May 21st, 2014, 01:11 PM	#8
drc84 ninjette.org member Name: Ralph Location: Baton Rouge, LA Join Date: Jun 2013 Motorcycle(s): 2004 EX250 Posts: 12	I'm bumping this with a video: Link to original page on YouTube. This is getting worse and I think it's going to cause a problem soon. Anyone have a recommendation of a guide to use to diagnose the problem or something?