KTM Military problems list

[Popex]

I thought since I am currently having problems with my 2003 KTM LC4 400 Military that I would start up 1 thread where people can post their problems (& hopefully solutions).


The problem I am having at the moment is the damn thing is overheating - this is the situation:
- 1st time overheating
+Bike on for 2 min to warm up
+Bike loses power higher in the RPM range and makes a funny noise then
+Ride bike for another 5-15 min and then whilst stopped waiting at a light the radiator hose attached to the engine block popped off and sprayed clean coolant on the street

+No idiot light went on telling me the fluid was too hot

Replace coolant, attach hose, replace air filter & test thermostat - it opens when put in a bowl of boiling water

- 2nd time overheating (Next time on bike)
+Warm-ish night of riding (plus hit every stop light)
+Bike on for 2 min to warm up
+Bike dose not lose power higher in the RPM range
+Ride bike for 30-40min - noticeably way too hot under the seat and generally everywhere
+ Again whilst stopped waiting at a light the radiator hose attached to the engine block popped off and sprayed clean coolant on the street...
+No idiot light went on telling me the fluid was too hot

Anybody have this same problem? I can only think blockage somewhere or bad water pump...

I also think I need to replace the heat senor for my idiot light...


EDIT - For PeerG's peace of mind... He was right... after getting through "MY" issues with the bike, I figured out the problem was not so much with the bike, but with me being a new owner of a bike I haven't gotten used to... see below for what was done to "fix" what most people would not have really had a problem with...

[Popex]

I am planning on getting out my temperature heat gun to try to locate where it is overheating & if there is a blockage in the system.

Any ideas how to test the water pump?

[Redboots]

Originally Posted by Popex

I am planning on getting out my temperature heat gun to try to locate where it is overheating & if there is a blockage in the system.

As you say it is popping the hose off, have you checked the head gasket?

I would have thought a blockage was low in the list... remove the thermostat, and disconnect one end of the top & bottom hoses and stick a hosepipe up it. Ideally in the reverse direction to the normal coolant flow.

Does it have a cooling fan? When does that cut in?

John

[PeerG]

I don't like this thread, cause I love the bike and the thread it suggests that the Military is particularly problematic ;-)

Most of the problems will also apply to other LC4s, so why don't we move this to the Adventure problems list thread? Just an idea to distract from the Military's faults...

Be that as it may, I'm afraid I can't help you with the overheating issue. Although I doubt it is a general Military problem, mine overheated only once and that happened at 35°C and when standing in city traffic, because the neutral revs setting was far too high (the bike was new and I didn't know how to adjust it). The light came on though and after turning the engine off for a few minutes it was fine again. No hoses came off. After adjusting the neutral revs it never overheated again, not even in the Buenos Aires traffic in January.

I'll check my LC4 repair manual for overheating problem solutions when I get home and let you know in case I find anything useful.

[PeerG]

Ok, these are possible reasons for overheating according to the Buchelli KTM repair manual (I'm not too familiar with the technical terms in English, so excuse bad translations):

- air-petrol mixture not correct (too little petrol)
- suction of secondary/false air
- thermostat opens prematurely
- too little cooling liquid
- clogged tubes
- air in the cooling system
- cooling unit is dirty (outside)
- waterpump isn't working
- thermostat remains closed
- motor of the fan isn't working
- switch of the fan isn't working
- foam creation in the cooling system
- tubes are buckled
- fuse of the fan isn't working
- too little oil in the engine
- oil pump isn't working or the oil circuit is clogged
- large oil carbon deposits in the combustion chamber

Hope this helps!

Peer

[Big Yellow Tractor]

The coolant system on anything shouldn't pressurise enough to pop a hose off. The rad filler cap should release allowing pressure out; normally via a catch-tank. Very high pressure does, I'm afraid point towards cylinder head gasket issues.

Are both the oil and the coolant clean ?

Any mucky residue on the filler cap ?

[Popex]

PeerG, haha, I understand what you mean... the guy I bought the bike from would have said the same thing.

I just had the temp gun out and just like the manual says when it gets to just around 90C the hose on the other side of the thermostat goes from a 20C difference to about the same temp as the hose on the other side of the thermostat...

The Fan came on 2 times when the radiator was reading around 100C...

It all seems like the cooling system is working as it should...

the bike was pretty much just idle for probably around 15-30min with an air temp of around 24C... should the bike get that hot that quick when I only rev-ed the engine a little a couple times?

I feel like I am making something out of nothing... but I can't figure out why would the hose have popped off?

The last time I was riding I did literally hit every stop light (which in Vienna are spaced out far enough to only sometimes get to 3rd gear), I had a passenger and it was about 20C out...

[bobthebiker]

at this point, I feel compelled to ask several things I notice.

what kind of hose clamps are fastening the coolant hoses? are they tight enough to hold well?

have you started the bike with the radiator cap off and looked to see visually if the motor is indeed movin coolant properly? I know this seems odd, but its a valid testing method. if your coolant pump works, you'll notice the fluid level drop down a bit and start to swirl in a way when you start the bike, if it isnt working, it'll just sit there.

have you checked the bulb for the coolant overheat warning light? its entirely possible that everyhing was working, and the bulb is simply blown out.

just some stuff for you to look at. failing that, do a leakdown test, and check your oil for coolant, along with the exhaust for a sweet scent, which would be coolant burning off(also explaining a pressurized system.)

[Popex]

OK, so, the bike is now purring the kind of purr that puts a smile on your face.

I had the luck of meeting a guy that has owned numerous LC4s throughout his life & he was able to help me out.

The bototm line was I haven't had a chance to get to know the bike to know was normal for the bike...

So the "problems" and "fixes" are as below:

Radiator hose popping off - new clamp - old one bad and vibrated loose

Bike operating too hot - idle set too high

Bike will die unless at a higher RPM - adjusted the air/fuel mix

Metallic rattling noise when not on the gas - shortened chain - no noise

Bike hard to start - dumb me learned how to properly kick start the bike
(although I am still having trouble with the electric start... I still need to test the battery... time is something I do not have a lot of)


So needless to say I am back and happy with my bike

[clintnz]

According to the manual for my 640 the fan should switch on when the thermoswitch in the radiator gets to 70 deg C, so you may still have a problem but it is easily fixed.

I just looked this up & tested my thermoswitch as the fan didn't come on like it used to during some slow offroad riding last week, mine wasn't switching until 100deg which is wrong so I'm getting a new one.

Cheers
Clint

[PeerG]

AAARRGGHHHH! My KTM Military got stolen, 3 weeks before my trip to Romania

If anyone sees one in Southern Germany (got stolen in Munich between Wednesday evening and tonight), challenge the rider!!

Peer

[Popex]

absolutly gutted for you PeerG.

I'll keep an eye out in Vienna... any markings on the bike that make it clearly your bike?

[Todd-Squad]

One thing that helped my 525 is I started using BMW coolant. I know that sounds stupid, but I'm convinced it is a much higher quality coolant that the Prestone I was previously using. It seems to allow the radiators and cooling fan to handle engine heat much better.