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Discussion Starter · #1 ·
Hello Family!!

I am almost due for my 600 mile service and I have notice coolant on the frame of my bike. It looks like it’s coming from the top right side somewhere but I can’t seem to find the cause.

Any suggestions will be very much appreciated and I will go to ktm workshop this weekend, I just want as much info I can get before I go.

Thanks in advance.
 

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Discussion Starter · #2 ·
I checked out the oil through the looking glass and thankfully it looks good, there doesn’t seem to have coolant mixed in the oil.
 

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Coolant on the frame is no indication of it mixing with the engine oil.
If heading to the dealers, just check if the coolant level in the reservoir remains between Min-Max and you will be okay.
Point out the suspected leak to the mechanic.
 

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Discussion Starter · #4 ·
Coolant on the frame is no indication of it mixing with the engine oil.
If heading to the dealers, just check if the coolant level in the reservoir remains between Min-Max and you will be okay.
Point out the suspected leak to the mechanic.
I checked the reservoir while bike was cold and the coolant was at minimum.
 

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Depending on how far your garage is, I would top up till the max mark before riding there. You can top up with distilled water, for now, if the garage is taking off the radiator they will need to refill with fresh coolant if it is only a hose fastener the amount between Min and Max is so little that you will be okay seeing you are heading into better weather over there.
 

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Top-right side is where the reservoir is, right? Most likely a leaky hose or clamp, should be an easy fix for the dealer. It needs to be fixed, of course, but your bike should be fine to make the trip to the dealer (unless it's far away), most of the coolant is down in the radiator.
If you're concerned about riding there, call them, send them those pics, that's what your warranty is for!
 

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Discussion Starter · #7 ·
Top-right side is where the reservoir is, right? Most likely a leaky hose or clamp, should be an easy fix for the dealer. It needs to be fixed, of course, but your bike should be fine to make the trip to the dealer (unless it's far away), most of the coolant is down in the radiator.
If you're concerned about riding there, call them, send them those pics, that's what your warranty is for!
Yes, by the reservoir. Thanks for the insight. Taking the bike in today. It’s a 30 min drive to the shop. I’m going to ride it over and keep an eye on the temps.
 

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Mine did this when new and it was the coolant cap not fitted correctly. The Coolant was on minimum. I topped up the coolant, tightened the cap, and all was fine after that.
 

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Discussion Starter · #10 ·
Hello again all. I just wanted to
Update you guys. The radiator wasn’t closed correctly. And does anyone know if this hose should be facing this angle? Upon inspection I noted that it was leaking coolant from this hose as well. I went ahead turned the hose so that exit point is facing to your left as opposed to down as shown in pic?
1F26216E-AFA8-4DE7-BC17-A98892404028.jpeg
 

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That is probably the overflow hose, see how high-mounted it is? The coolant normally never touches that opening, unless you're boiling. The purpose of that hose is to evacuate boiled coolant from the reservoir to relieve pressure, at which point it doesn't really matter where it's pointing, the bike will just piss itself (and you'll need a refill once it's cooled).

It's surprising that you've found it leaks coolant, was your reservoir overfilled so much?
 

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Discussion Starter · #12 ·
That is probably the overflow hose, see how high-mounted it is? The coolant normally never touches that opening, unless you're boiling. The purpose of that hose is to evacuate boiled coolant from the reservoir to relieve pressure, at which point it doesn't really matter where it's pointing, the bike will just piss itself (and you'll need a refill once it's cooled).

It's surprising that you've found it leaks coolant, was your reservoir overfilled so much?
It was not overfilled. Once I noticed a coolant leak I check the resivoir tank and it was at minimum. could the lack of pressure in the system due to unsecured radiator cap cause it overflow ? The system seems good now.
 

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could the lack of pressure in the system due to unsecured radiator cap cause it overflow ? The system seems good now.
I believe so. These engines have been reported by many to operate on the hot side. Fans running a lot once at operating temp, in warm weather, etc. So you would think the cooling system would boil easier without any pressure build up in it due to the loose radiator cap. My opinion
 

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Discussion Starter · #16 ·
Angle of the hose looks much the same as the parts diagram picture.
MotoMirius From YouTube, thank you so much. Your video was honestly what helped me solve this issue myself. If it wasn’t for you I wouldn’t have the courage to take off the fairings and do a flush and bleed on the system (I switched over to engine ice). Thank you for warning about not over tightening the bleed screw and etc! You are a hero good sir, My mentor! It is incredible how much I have learned from you!! My chain seems like it came loose from the dealer. I checked the tension as you described in detail and when I push up where you show to check tension the chain will go up and touch the frame. Not much tension ! Anyway I guess that’s a different story for a different day. I Will muster up the courage to do so myself as I watch your video. Thanks to you when I do these jobs myself at least I know it’s done right, and without being charged $100 an hour for work that may or may not be rushed and careless. And my KTM dealer is far away and didn’t want to pay any service and fees. Currently saving as much as I can due to coronavirus outbreak.

Anyway, I inspected the hose angle on your video where you replace your radiator and it seemed your overflow hose (or whatever you would call that hose) was facing towards the rear of the bike so I did the same.

after tightening the rad cap and redirecting the hose to face the rear I haven’t seen coolant anywhere, and I have ridden hard. Everything seems to be working wonderful and smooth after self service. I couldn’t be happier. This is my first street legal motorbike and I couldn’t be happier!! Cheers!!
 

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Discussion Starter · #17 ·
Still leaking through the overflow hose as pictured.

i am thinking this is due to a bad radiator cap, causing the coolant to overflow like this. Going to try and swap out the rad cap when I get the chance. Mean while do any of my fellow peers have any thoughts?

p.s the bike isn’t over heating or anything.
 

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Still leaking through the overflow hose as pictured.

i am thinking this is due to a bad radiator cap, causing the coolant to overflow like this. Going to try and swap out the rad cap when I get the chance. Mean while do any of my fellow peers have any thoughts?

p.s the bike isn’t over heating or anything.
Is the expansion bottle empty or really low now (assuming you filled it to the correct level just recently)?
If it is then I hate to say it, but this is typical of a blown head gasket. When the gasket fails the cylinder pressure leaks into the coolant circuit and forces the liquid out.
Given it's a new bike I'd get it straight to a dealer, and if it's more than a few miles away it would be better to get KTM to make the decision in writing/email to you if you should ride it there, or if they should recover it. If the coolant level drops too far it will overheat and wreck the engine.
Hope I'm wrong, but that's what I'm thinking having read the thread.
Let us know how you get on.
 

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Discussion Starter · #19 ·
Is the expansion bottle empty or really low now (assuming you filled it to the correct level just recently)?
If it is then I hate to say it, but this is typical of a blown head gasket. When the gasket fails the cylinder pressure leaks into the coolant circuit and forces the liquid out.
Given it's a new bike I'd get it straight to a dealer, and if it's more than a few miles away it would be better to get KTM to make the decision in writing/email to you if you should ride it there, or if they should recover it. If the coolant level drops too far it will overheat and wreck the engine.
Hope I'm wrong, but that's what I'm thinking having read the thread.
Let us know how you get on.
Hello and thank you very much for your reply.

after doing a coolant flush and bleed, I topped it to the max fill line on the expansion tank. I noticed the leak from the overflow hose didn’t stop so I drained some coolant out and right now I have it to about 75 percent full on the the expansion tank. It is still at 75 percent full on the expansion tank, the leak is so slow that I have not yet notice a big drop in coolant in the expansion tank. It’s still at about 75 percent full.

I am hoping it’s a bad radiator cap causing the coolant to boil over? Replacing the cap will be my last attempt on figuring this out on my own. I will definitely keep you guys updated and let you all know what happens.

thanks for everyone’s input.
 

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I’m assuming you are leaving the tank panel off. If so you should be able to see the conditions in which this happens. I’m tending to agree with an over pressure situation and not the rad cap. Is the fan kicking in?
 
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