More overheating issues

[zaster]

A dozen my of motorcycle friends and I decided to make our annual trip from Albuquerque to Telluride, CO to ride for three days in the Rockies. The bike performed beautifully on the 500 mile trip and did well keeping up with the liter bikes. The next day 30 miles into our ride the bike started to overheat. I let it cool off and limped back to base in 7 mile intervals. Checked fluids, fuses and radiator cap which were all good. The fan kicked in once the temp. got within 2 bars of H. Could it be the water pump? I'm bummed out not being able to ride in these beautiful mountains.

 

[Diploman]

I believe there was an advisory from the KTM racing team to check that the water pump impeller bolt is tightened to spec (check owner's manual). Apparently there were a few instances of the bolt coming loose on race bikes. If the impeller stops working, coolant will not circulate.

 

[=maz=]

Fuck me...will it ever stop? Sorry to hear of your woes Zaster.
I've done a second head gasket now also...despite the special Gaskets and milling.

 

[zaster]

Thanks guys, I will bring the bike to my dealer by Wednesday and let you know what they found.

 

[zaster]

Checked in with the dealer today and was told that it must have been an air bubble in the cooling system.
They can't tell me how this happens and how to prevent it from happening again.
Anyone have the same issue or has heard about this?

 

[Fasteddy]

Yes, but it would not have gone 500 miles, not even 5 miles without over heating with a large amount of air (air blocked) in the system, and the air would have to have been introduced after draining coolant and refilling without proper bleeding. Some bikes / cars are more prone than others to this issue.
Maybe it was running lean due to inability to compensate for higher elevation?

 

[zaster]

Thanks Fasteddy. I'm running a PCV with wideband auto tune so the fueling should have been ok.
The bike was kicking butt going from 5,000 feet to 10,000 feet not missing a beat and keeping up
with most of the liter bikes. It felt like the cooler mountain air actually increased it's performance.

 

[Bagwell]

what mods, fixes, etc have been done to this bike?

 

[zaster]

what mods, fixes, etc have been done to this bike?

PCV with wideband auto tune and 1.6 bar radiator cap from MNNTHBX plus Yoshimura RS-9 Dual Slip-ons.

 

[Fasteddy]

Sounds like fueling was not an issue and you would expect better performance from cooler dense air so that shows the auto tune was doing its job.
Are you still running the original coolant? if you changed it out (engine ice / etc.) did you keep track of how much you put back in?

 

[zaster]

Sounds like fueling was not an issue and you would expect better performance from cooler dense air so that shows the auto tune was doing its job.
Are you still running the original coolant? if you changed it out (engine ice / etc.) did you keep track of how much you put back in?

Never touched the cooling system. Was thinking about using the Evans High Performance Waterless Coolant though.

 

[Fasteddy]

Never touched the cooling system. Was thinking about using the Evans High Performance Waterless Coolant though.

Check out page 146 of the owners manual for how to bleed the air out of the cooling system, Also a trick that works good is to squeeze the upper radiator hose repeatedly to force air out, like a pump, then let it sit for awhile with cap off and repeat.
I plan on changing to engine ice at some point, I run that in both my other water cooled bikes. A few months back I rebuilt the water pump in my SuperDuke and getting all the air out was a couple of day process, but the LC8 engine is known for that.

I don't see a bike doing 500 miles, then getting air blocked and over heating unless there is some place for the coolant to go so it can be replaced by air.

Is the bike back to running fine now then? with basically 'no trouble found' ?

 

[KTMGene390]

The bike was kicking butt going from 5,000 feet to 10,000 feet not missing a beat and keeping up
with most of the liter bikes. It felt like the cooler mountain air actually increased it's performance.

FWIW, there is less oxygen available for combustion at significantly higher elevations resulting in less fuel being able to be burned. Less fuel burned, means less power produced. Not so sure on your cooling issues unless you blew some kind of gasket or a known issue with the propeller shaft bolt possibly being loose from the factory. Sounds like what people are saying about air bubbles being in the cooling system. There is a air bleed screw on the top left side of the radiator that needs to be open per service manual instructions when filling the system.

 

[btalont]

I have been tracking my bike here in South Texas, hot and humid. I did 3 things based on discussions here. I changed the coolant to engine Ice, made sure to flush and circulate water through the engine and radiator several times and then flushed once with the Ice so I was assured of good fluid concentration. Second, I pulled the fan and cut away a majority of the shroud. I was shocked ho much that shroud blocks airflow. Third I added the Radiator cap from MMTBH. I run the Bazzaz with the self mapping fuel module. Have a open K&N and aftermarket pipe. Fueling is so much better, the self mapper really adding fuel in, especially the mid-range. Ran the bike hard July 30 and coolant was stable and even one bar cooler than before. Street riding the fan seems to run less now as well. Hope to fend off the head gasket failure for as long as possible!

 

[MotoKam]

Originally Posted by yo69xl
This is the one Spal 30103011 5.2" puller fan

Here you will find everything you need to know about the SPAL Fan , including a step by step replacement tutorial .Spal Fan Instal How To - KTMDuke 390 Forum



This is a fantastic tutorial. The only thing I did differently for my overheating RC390, was to carefully remove the connector blades from the plastic plug. The blades are the same except that the middle hole needs to be punched out to clip into the KTM fan plug. This will prevent any need to cut the wires or splice anything together. It's as solid as the stock connection.

It's been 1000 miles since I did the upgrade and it works brilliantly!

The temp gauge never gets close to the top anymore. I can feel the hot air blowing through at stop lights around town (that might be rough on 100+ degree days, oh well). But it doesn't overheat at all any more.

I posted the above last October and I stand by this fan upgrade. The cost was less than $100 and a couple hours of my time.

It's been 14,000 miles since the SPAL fan replacement and there has been no hint of overheating since.

 

[SneakyOwl]

Exactly what I need. Fan ordered

 

[stevieboy]

I got mine for $40.00 shipping included.

 

[zaster]

Check out page 146 of the owners manual for how to bleed the air out of the cooling system, Also a trick that works good is to squeeze the upper radiator hose repeatedly to force air out, like a pump, then let it sit for awhile with cap off and repeat.
I plan on changing to engine ice at some point, I run that in both my other water cooled bikes. A few months back I rebuilt the water pump in my SuperDuke and getting all the air out was a couple of day process, but the LC8 engine is known for that.

I don't see a bike doing 500 miles, then getting air blocked and over heating unless there is some place for the coolant to go so it can be replaced by air.

Is the bike back to running fine now then? with basically 'no trouble found' ?

The only thing they found after pressure testing the radiator and cap was that it was low on coolant.

The odd thing is that I checked the level the next morning after it had overheated and coolant spilled out when I popped the cap.

They have no idea where the coolant might have left the system, what caused it or how to prevent it from happening again.

What bothers me is that I don't know if and when this could occur again after missing out on three days of riding and having to get the bike hauled back home.

You guys think it would behoove me to contact KTM North America to see if they might have any answers?

 

[Fasteddy]

I doubt KTM NA would have much to add, If it were me I would check the oil level to ensure the crank case is not taking on coolant, maybe pull the air filter out and look at the crankcase breather return area for signs of coolant / oil mix (milky white), make sure it's topped off and take it for some rides closer to home and make sure it does not empty the reservoir or over heat.

Did they say how much they had to add?
When you popped the cap off was the coolant spilled out from the reservoir?
When I changed the cap on mine I pinched off the reservoir tube with a pair of hemostats so I only lost a very small amount.

 

[zaster]

I doubt KTM NA would have much to add, If it were me I would check the oil level to ensure the crank case is not taking on coolant, maybe pull the air filter out and look at the crankcase breather return area for signs of coolant / oil mix (milky white), make sure it's topped off and take it for some rides closer to home and make sure it does not empty the reservoir or over heat.

Did they say how much they had to add?
When you popped the cap off was the coolant spilled out from the reservoir?
When I changed the cap on mine I pinched off the reservoir tube with a pair of hemostats so I only lost a very small amount.

They just said it was pretty low. The reservoir was filled half way and the radiator looked toped off when I removed the cap.
I like your process for stopping the overflow but didn't have all my tools with me while on the road.