FIXED! Mysterious (maybe not) coolant leak left side

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Bought this '03 1300 in May, and have thoroughly enjoyed a trouble free summer of riding approx 5K. I have seen the occasion drip spot in my driveway, and I wasn't too concerned but a bread plate sized puddle of coolant was found at one point. I made a short run to a buddys place Sunday, a bit cooler here but not cold and when I stopped I observed a healthy piddle of coolant coming from the center of the lower cowl. I went home and proceeded to tear off the left side mid fairing, as the drip was located in line, perhaps slightly ahead of the expansion tank, about 4 inches from the center edge of the lower cowl. I attempted to get the bike up to temp sitting as well as riding but was unable to reproduce the leak. Im going to block the rad next and try again. I did notice the coolant level looks to be too high, cold it is above the top mark, and I also noticed the main large hoses collapse when the bike cools, is this normal? I don't believe the coolant overflow was the source because the drip was marked inside the lower cowl and did not exit from the hose.
Any leads would be greatly appreciated. Thanks in advance!
 

SupraSabre

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When the overflow bottle is too full, they have been know to spit out some of the excess.

The guy that bought my '04#2 overfilled the overflow and was then wondering why so much coolant came out. When I looked into the bottle, it was a good 1" above the full line! :doh1:

I'm not sure just where his came out of either...it wasn't the overflow bottle hose?

When you look down the throat of the bottle, you should just see a reflection when the fluid is at the correct level. If all else, stick a dowel (or something) down it, and see where the fluid is...it should just barely on the bottom of it.
 
OP
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Not the overflow hose. I have not added coolant since I bought it, and it seems weird that it would suddenly purge excess coolant after all the riding I have done so far this year, and if it did, it would have exited through the overflow, but the drip mark was on the inside of the lower cowl. Rad hose and head gasket are all I can think in that area.
 

CYYJ

Michael
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Here is a possible scenario that may fit your symptoms. There is a blockage in the tube to the coolant reservoir plastic bottle in front of your left shin, or in the bottom of the bottle itself.
Expanding fluid cannot pass into the reservoir because of the blockage, but it is under pressure now, so it expands the hose instead. As a result, the hose looses its seal around the nozzle at the bottom of the reservoir and fluid escapes. It gets blown out.

When the coolant cools, it contracts. Because there is a blockage, it cannot suck any replacement fluid from the reservoir so it sucks in whichever tubes are prepared to give way.
John's hypothesis above makes a lot of sense in light of the history the OP has provided.

@BoostedLSS , what I suggest you do first (simply because it requires the least amount of disassembly) is remove the Tupperware panel from the left side of the bike, so that you have full and unobstructed access to the coolant reservoir bottle. Remove the bottle and thoroughly clean it out - it will probably be full of gunk and crap. To thoroughly clean the inside of the bottle, add a handful of rice to the bottle, then fill it up halfway with Simple Green or similar, and shake it aggressively - that will scour the scuzz off the inside of the bottle. Before you reinstall it, use a Magic Marker (permanent ink black felt pen) to highlight the raised lines on the bottle that show the upper and lower limits - that will make it easier for you to check the level in the bottle in the future.

Also, before you reinstall it, check to see that the hose at the bottom of the bottle (the hose that goes to the neck of the radiator cap) is not blocked. The easiest way to do this is to go to a drugstore and buy a really large syringe (the biggest one they have) and use the syringe, without the needle installed on the end, to blow air up the hose. I suggest you disconnect the upper end of that hose from the radiator neck before you do this, in case crud comes out - you don't want the crud falling in the radiator.

Use the syringe to do the same thing with the coolant bottle overflow hose (the hose that exits out the bottom of the motorcycle). That hose can become blocked at the lower end from road debris & mud.

When you reassemble, confirm that the little clamps that hold the hoses onto the bottle (and the radiator neck) are holding the hoses snugly - that will rule out a leak at the end of the hoses.

Lastly - this is unlikely, but possible: If you found the coolant leak on the floor the day after you did a really, really thorough washing of your motorcycle - squirting lots and lots of water in the front of the motorcycle, near or above the top of the radiator - it is possible that you simply washed out coolant that had leaked at some time in the past, then dried up in the "V" in the middle of the engine. If this is what happened, the green liquid (wash water mixed with previously dried-up coolant residue) would have come out the Square Hole on the right side of the engine.

Michael
 
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While you are in there, check all the hoses that you can see. Radiator hoses in good condition are not soft and squishy and your bike is 16 years old - some might be ready for replacement. Syringes from the drugstore can be expensive or difficult to buy sometimes. Get a plastic turkey baster from the supermarket I have a general rule that any kitchen gadget used for automotive or mc maintenance never sees food again (like funnels, etc.). Winter is coming and you might consider deferring some maintenance until your winter layup (whats your winter weather like in BC?) and then thoroughly go over your cooling system.
 

Andrew Shadow

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I have seen the occasion drip spot in my driveway, and I wasn't too concerned but a bread plate sized puddle of coolant was found at one point. I made a short run to a buddys place Sunday, a bit cooler here but not cold and when I stopped I observed a healthy piddle of coolant coming from the center of the lower cowl
This scenario is consistent with loose hose clamps on the various coolant hoses under the throttle bodies that need to be snugged up. This typically manifests itself when ambient temperatures begin to cool off.
I did notice the coolant level looks to be too high, cold it is above the top mark, and I also noticed the main large hoses collapse when the bike cools, is this normal?
If when you write "the main large hoses collapse" you mean the radiator hoses that is not normal. This scenario suggests that you have a defective radiator cap or a restriction in the hose between the radiator and the overflow tank. The expanded coolant gets expelled in to the tank when the engine is hot. When the engine cools off the coolant is not being drawn back in to the radiator because of the defective cap or restricted overflow hose. Repeat this several times and the tank becomes overfilled and drains out the overflow. The inability of the system to draw coolant back in to the radiator as the engine cools creates a vacuum in the cooling system that collapses the hoses.

Maybe you are suffering from two separate issues simultaneously.
 
OP
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UPDATE: So it appears I may have been mistaken in assuming the coolant did not exit through the overflow hose, I was under the impression the hose was tabbed together with another hose and visible below the lower fairing. Apparently it was just tucked behind the frame and did not extend to the bottom like the other hoses do. I swapped in fresh coolant and forked out $35CDN for a new rad cap, which I suspect was the problem, as the return line was not blocked and after cooling off the main hoses are still in the correct shape. Many thanks to the experts here on this forum in support of one cheap bastard, ME!

Thanksgiving holiday was Monday here in Canada, which was spent riding the Pacific Marine Circle here on southern Vancouver Island, it's a great bike road, with lots of twists and a minimum of fuzz.

Thanks guys!
 
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