Date: 28-03-24  Time: 16:54 pm

Author Topic: Ahh Coolant leak!  (Read 1216 times)

Arfa

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Ahh Coolant leak!
« on: 08 September 2018, 02:53:07 pm »
I appear to have small leak along seal on thermostat (bit below main coolant filler cap under tank).

Pretty certain it's the o-seal on this thermostat. Doesn't appears to originate from the hose or cap. (Cap was new a couple of years ago, as old wasn't holding pressure). On pressure testing the system, I get a a few small drips forming at the base of thermostat only. Anyone done this job of replacing and dismantling the thermostat? Any tips, tricks or advice?

Bit worried the attached hoses aren't going to like this job, as they're looking pretty old and flakey. And still we haven't sorted out any silicone hose group buys...  :eek 
Anyone had any joy buying random silicone sections and bends to replace some of the hoses on the FZS600? For example:
http://www.jsperformance.co.uk/silicone-hoses/elbow-silicone-hoses/30-degree-elbow-silicone-hoses
Do we have any knowledge on what bends might cover what bits of the system?
« Last Edit: 08 September 2018, 02:56:09 pm by Arfa »

His Dudeness

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Re: Ahh Coolant leak!
« Reply #1 on: 08 September 2018, 03:09:44 pm »
Yes it's leaking from the o ring in the middle of the thermostat. The hoses should be fine. New o ring and coolant and it should be sorted. It's an easy fix. Get the part number from the part number manual in the download section.

bandit

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Re: Ahh Coolant leak!
« Reply #2 on: 08 September 2018, 07:36:10 pm »
As His Dudeness said you should be able to split the housing by removing the three bolts without touching the hoses. :)


 https://www.wemoto.com/bikes/yamaha/fzs_600_fazer/98-99/picture/thermostat_housing_o_ring     

Jules-C

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Re: Ahh Coolant leak!
« Reply #3 on: 09 September 2018, 10:40:44 am »
And don't overtighten the bolts because half the housing is plastic.  The official service manual has the wrong torque settings

Arfa

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Re: Ahh Coolant leak!
« Reply #4 on: 09 September 2018, 12:15:43 pm »
And don't overtighten the bolts because half the housing is plastic.  The official service manual has the wrong torque settings


My Haynes book quote 10Nm - sound about right?
Though TBH not sure I'll get torque wrench in there without removing all hoses and pulling lot out. 10Nm sound about hand tight anyway.

Jules-C

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Re: Ahh Coolant leak!
« Reply #5 on: 10 September 2018, 12:39:57 pm »
That's what official manual says Haynes probably copied.  I think I did mine about 6Nm you only want to crush o'ring slightly