Mayonnaise in engine. Head gasket blown (KTM 640 Adventure)

[D0dja]

Last weekend I stripped around the top end to check my valve timing. And found in the oil hoses from frame thick, white gloop.

I'm thinking head gasket leak. I noticed my coolant level kept dropping, but blamed my radiator cap not sealing properly.

I don't want to even contemplate what this means.

Someone please tell me there is another possible explanation?

Apart from completely tearing down the engine, is there any way to test where the problem might be?

[Dexter2811]

Yup, those are a blown head gasket symptoms... you'll have to, at least, remove the head and check it...

[crazybrit]

Originally Posted by D0dja

Last weekend I stripped around the top end to check my valve timing. And found in the oil hoses from frame thick, white gloop.

I found same once in my SXC hose. Creeper told me it was nothing to worry about. I can't find the message anymore where he explained what it was.

[Luke]

Could be the water pump seals. Check it while you're on your way to the head gasket. When my head gasket broke it was sudden, not gradual like you're describing.

How fast are you losing coolant?

If were just goop in the breather hose without losing coolant that it could just be an oil/condensation mix. What does your oil look like? Oil or chocolate milk?

[clintnz]

Originally Posted by Luke

If were just goop in the breather hose without losing coolant that it could just be an oil/condensation mix. What does your oil look like? Oil or chocolate milk?

Most likely this if it is the breather hoses where the goop was, & there is no oil in the coolant or vice versa. I usually see a little milky goop in the engine - frame breather pipes when I remove them.

If I overfill the rad on mine it always spits out the excess coolant until it finds it's happy level just at the top of the core while upright.

If you do have a problem with the water & oil not staying where they should it is more likely to be the water pump needing a rebuild than a head gasket issue. It's usually pretty easy to see if the water pump is shagged when you strip it down.

Cheers
Clint

[KTM AL]

Probably condensation if your antifreeze isn't going low
If your engine oil is milky and antifreeze is going low
than its probably your water pump seals, which can be rebuilt or replaced, rebuilt mine for about $60.00

[swimmonkey]

Coolant and oil. Don't put it on a sandwich!

[bmwktmbill]

Waterpump, check the bearing numbers and the seal numbers in the parts book, you can get them from any bearing house...the shaft is the problem if it is scored.

Most of us own a couple ruined ones.
PIA.
bill

[Ride Now]

Oh great; this is probably gonna start a "What brand of mayo is best for my engine?" threads..............

[slackmeyer]

Originally Posted by bmwktmbill

Waterpump, check the bearing numbers and the seal numbers in the parts book, you can get them from any bearing house...the shaft is the problem if it is scored.

Most of us own a couple ruined ones.
PIA.
bill

+1, KTM waterpumps just do that.

[D0dja]

Thanks for the pointers, gents. After giving it a think, reading some other threads and talking to some folks, I'm inclined to believe it's the inner waterpump seal. Plenty of evidence points to this.

Also, believing it's the waterpump seal is much nicer then believing it's head gasket,

After cleaning out as much goop as I could find, topping everything up, and going for a couple of hours ride, the coolant level did not drop a lot, and the bike seems to be running fine. I've not been riding that much recently, which would seem to make it more likely a seal got stiff than the head gasket would suddenly let go.

Found a really good step by step to rebuild the waterpump (and hopefully fix an annoying oil leak from the top of the head that's been irritating me for years). Will order the parts and do a rebuild in a couple of weeks (currently in midst of moving house).

[bmwktmbill]

While you are at it better do the cam followers or you will cry.

That's the standard.
bill

[D0dja]

Ah bollocks. Rebuilt the water pump with new bearings, seals, etc. Took a bit of time to seal up exhaust port bolt oil oooze, and re-seal the valve cover.

All tight as a drum, no more oil-slicks down the side of the engine.

Also re-faced the radiator mouth -- it was a bit scored and pitted and the cap was leaking. Took it for a couple of good hard runs and pressure was holding, coolant levels stable.

Then big offroad ride on Saturday. Temperature went ballistic, check the radiator, coolant almost gone.

I had noticed a lot of white smoke from the exhaust when starting -- in hindsight it looked more like steam.

Looks like the head gasket has failed.

I am not happy.

At all.

[bmwktmbill]

Can't say I blame you, been down that road myself...twice.

Second time I lost the piston due to cracked ring(s). I know it's an extra step but if it was me and especially if you have run some shit gas I'd consider pulling the barrel and check the rings.

How's the bore look?

http://advrider.com/forums/showthrea...ghlight=piston

pics here...
http://advrider.com/forums/showthrea...ghlight=panama

and here...
http://advrider.com/forums/showthrea...ht=overheating

bill