Grey gunk in my coolant system!

12 replies to this topic
  • Jmont31

Posted January 23, 2015 - 06:53 AM


ImageUploadedByThumper Talk1422024381.911826.jpg ImageUploadedByThumper Talk1422024392.795726.jpg ImageUploadedByThumper Talk1422024405.263442.jpg .

I was given coolant that freezes at 32 degrees, and didn't find out until I saw the remaining bottle of coolant frozen on the bench. Brought the bike in the house and let it thaw for a week. When I drained it not much came out and it came out in clumps this is what it looked like when I dug deeper. Any ideas or advise as to what to do or what the hell happend?

  • Swes

Posted January 23, 2015 - 07:06 AM


It looks either like an extremely excessive use of sealant or somebody used one those radiator stop leak bottles in it entirety without mixing any coolant (50/50) 


Not much I think you can do that has any absolute certainty other than doing a full break down and clean everything out piece by piece but since the previous owner used a stop leak or sealant one would start looking for where the leak was.


You could try one of those radiator coolant flush mixes ( follow the ratios  of Distilled water to flush liquid they recommend lest you cause more problems) after you rinse the crap out of it with the garden hose

Edited by Swes, January 23, 2015 - 07:13 AM.

  • Krannie McKranface

Posted January 23, 2015 - 10:25 AM


That's stop-leak, a SERIOUS no-no for your bike.

You need to pull the head off, and inspect the water jackets, pump, radiators, etc.

  • Jmont31

Posted January 24, 2015 - 07:48 AM


Thanks guys. I don't think it's stop leak. My buddy sold my the bike a couple years ago. He bought it brand new in 2010. Could it be the coolant coagulated after being frozen? Or maybe not enough coolant and the bike ran really hot? It kinda does look like a stop leak tho. But I drained it and refilled the system myself when I pulled the motor to have it rebuilt last summer.

Edited by Jmont31, January 24, 2015 - 07:55 AM.

  • Hunter_zack

Posted January 24, 2015 - 08:37 AM


Looks to me like bars leak. We put the heavy duty kind in a beater car one time and it came out in globs just like that. Reminded me of grease. Maybe try sticking a garden hose in a port and flushing it?

  • LoonRider

Posted January 24, 2015 - 09:29 AM


Yeah I was thinking you could just unscrew the coolant drain bolt and radiator cap, And just stick the hose in the full port to flush it out. Worth a try.

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  • Jmont31

Posted January 24, 2015 - 01:18 PM


Thanks guys. I'll give it a try

  • LoonRider

Posted January 24, 2015 - 01:27 PM


Maybe even try to remove the impeller before trying it so nothing gets stuck in the impeller?

  • Goforaride

Posted January 24, 2015 - 03:02 PM


Looks like a rat died in there! Buy 10 gallons of distilled water and flush it over and over. If its not perfectly clean by the time your done tear her apart

  • Jmont31

Posted January 24, 2015 - 06:53 PM


One of my buddies says I might have blown a head gasket

  • Goforaride

Posted January 24, 2015 - 11:16 PM


Is your oil milky?

  • Jmont31

Posted January 25, 2015 - 08:47 AM


ImageUploadedByThumper Talk1422204463.013859.jpg No

  • Jmont31

Posted January 25, 2015 - 08:49 AM


Ha! Needs a change though

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