KTM 525 Smoking/Head Gasket or worse??

[ChrisCrash]

Posted from "MLK ride"

Was having a great ride in Arkansas when i just happened to be in front of an RV park when the bike stalled, was smoking from the radiator and smelled like radiator fluid. I rolled in and quickly saw a loose radiator hose leaking. Radiator was just about empty. Of course the first thing I did was poor cold water in (arrr!!!) my very hot engine. Let it stand for about 30 minutes then was able to jump start it. At first ok but then after about 10 sec large plumes of white smoke out the radiator. I shut it down and a very nice lady drove me to my trailer.

This morning the radiator was down again about 1-2 cups. I filled and started. Started right up but lots of white smoke or maybe more blue color too. Smell was like oil and at the tail pipe a very thin/watery oil substance. I drained the oil and it was chocolate milk. The wife is complaining the whole house stinks!!!

Hoping this is something like a gasket. I am no mechanic but thinking I may try to tackle this myself. Questions/comments/insults all welcome.

[Savage]

Yes it sounds like its the head gasket. Only way to know if its just the gasket or worse is to open it up. After that its over my head.

[ChrisCrash]

Its all over my head. Going to see about ordering the manual tonight.

[HanesAnizer]

Hopefully just a head gasket and not something more sinister like a cracked head or cylinder.

[katbeanz]

My buddy Hayduke had an annoying leak on his 525 that slipped past his mechanic. With some coaching he used a piece of glass and 320 grit paper and lapped the head flat again so the gasket could seal. If it got hot, I'd make sure it's still flat.

[ChrisCrash]

Pulled the top end yesterday. Head looked a little rough but flat by my tools. Head gasket looked ok.
Big surprise was the top of the piston was chipped in two areas under the intake valves. Cylinder looked ok. It had some scuffs above TDC but not a scratch otherwise. The rings looked shot. No cracks anywhere that I could see. Took the parts to Letko. They are going to go over it tomorrow, pull valves, etc. I was only minimally chastised for not bringing it in for a leak down test ahead of time but they were very nice about it. I hear water pump seal can be a problem.

[ChrisCrash]

Katbeanz, I have been looking at sending the head off to get cleaned and resurfaced if needed. May do it anyway even if it looks ok by Letko. Thanks

[ChrisCrash]

Ok so after about 15 hours of test rides I think I can say my 525 is "...back baby!!" I did spend a small fortune in fingernail clippers and hand cleaner getting the job done, not to mention the copay for my MRI and pain mg shot after I herniated a disk in my back pulling the motor apart--all worth it of course.
When I got the parts back from Millennium the cylinder was plated, new valves and seats, head cleaned and new piston with rings.
I learned the hard way about placing the rings in the right spots when it started smoking after putting it all back together the first time. Then after rebuilding it for a second time I dropped a copper washer through spark plug hole--dang!! Third time pulling it and putting it back together, voila, it SCREEMS!!
My world is complete again.

[Hockey Dad]

Chriscrash

Just bought a 06 ktm 525. How many miles and hours are on your bike. Mine has 270 hrs. and 10,200 miles. The majority were "Super moto" miles. Don't know if thats a positive or not. One friend said its probobly ready for a "freshening up" soon. Didn't want to hear that.

[ChrisCrash]

About 250 hours on mine. I have the timing chain tool if you decide to go after it. Mine does seem to run better with a fresh topend.

[ChrisCrash]

And about 5,000 miles.

[Hockey Dad]

Thank you for the info..