Coolant Woes #2

[Cagey_Thoughts]

Hi people... 
ok... I am now near the end of my mechanical expertise... lol... so, if anyone has any ideas... please???  otherwise 'topping up coolant' will be another checklist addition to oil, tyre pressures and chain... lol
The Fazer is still spewing out its coolant through what seems like the expansion tank vent pipe... Although having taken some more pictures of the residue... It seems a little high on the swing arm??? If I can remember how to post pics I will attach them...
Anyway... checked all the waterways with high pressure hose and air compressor... no blockages... fitted new hoses... thermostat and cap... I have run the engine with the bike on the bench with the cap off to see if there are any air pockets.... and there is coolant passing through the cap housing so it looks like the water pump is working... so I am at a loss now...
the bike is back on the bench ready to be worked upon/stripped if necessary... but here in France I cannot run the engine up (unless I am going out for a ride) or run power tools etc outside of certain times... there are really strict rules regarding 'quiet times'... 
cheers peeps...

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p.s. the expansion tank is full of coolant...

[Faze2]

Dumb question, but when you say expansion tank is full you mean to the line not to the top of the tank filler ? Just to clear that up.

[Cagey_Thoughts]

Dumb question, but when you say expansion tank is full you mean to the line not to the top of the tank filler ? Just to clear that up.

Hi Faze2... no not a dumb question at all... right up to the top of the filler neck... Its a wonder that the cap hasn't been pressurised off... If that where the pressure is coming from???  
There's no oil in the coolant and no coolant in the oil.  (My thinking there head gasket maybe???)
I have just double and triple checked my hose routing.. (the bike has had a chassis up rebuild... but I have had the bike from new... and I have worked on it for a long long time...

[Faze2]

Dumb question, but when you say expansion tank is full you mean to the line not to the top of the tank filler ? Just to clear that up.

Hi Faze2... no not a dumb question at all... right up to the top of the filler neck... Its a wonder that the cap hasn't been pressurised off... If that where the pressure is coming from???  
There's no oil in the coolant and no coolant in the oil.  (My thinking there head gasket maybe???)
I have just double and triple checked my hose routing.. (the bike has had a chassis up rebuild... but I have had the bike from new... and I have worked on it for a long long time...

Hi, ok so the expansion tank is there for the expansion of the fluid as it heats and if its full it has nowhere to go and pressurised liquid will find its way out of any week spot.
There are marks on the side of the plastic expansion tank under the seat , just needs to be to the upper line. This may be your issue. 
Most definitely could be the expansion tank breather.

[Grahamm]

The point of the tank is to contain the fluid as it expands when the engine gets hot. It's designed to overflow if it gets too full.

When you've run the engine and it's cooled down, the coolant in the radiator will contract and the contents of the reservoir will be sucked back into the system.

As long as the level in the expansion tank is above the "Low" mark when the engine is cold, you shouldn't have a problem.

[Faze2]

The point of the tank is to contain the fluid as it expands when the engine gets hot. It's designed to overflow if it gets too full.

When you've run the engine and it's cooled down, the coolant in the radiator will contract and the contents of the reservoir will be sucked back into the system.

As long as the level in the expansion tank is above the "Low" mark when the engine is cold, you shouldn't have a problem.

[Cagey_Thoughts]

Hi peeps... thanks for the replies... I haven't taken all the hoses off yet... but by the look of it there is little to no coolant left in the block or radiator.. but the expansion tank is full to the brim... with a completely cold engine... when I filled the system I put in 2 litres of coolant.... with the expansion tank at the lower level... so I'm a bit stumped... I can do more tomorrow... Sunday is a 'quiet ' day here in France... lol

[Cagey_Thoughts]

Hi all... I have emptied all the coolant out of the bike...
In the Rad/Block/Water pump there was 1 litre 200 ml... and in the expansion tank there was 350ml... making a total of 1ltr 550ml... so not a great difference to the coolant level of 1.95ltrs + about .6 ltr in the expansion tank itself...
I guess the big question is... why so much coolant in the expansion tank??? why has it not syphoned back into the system???
I have removed various hoses and blown through with an air hose (inc rad)... there are no blockages in the system... including through the expansion tank feed and vent.... so any thoughts peeps??? all suggestions greatly received...

[Grahamm]

At this point, I'd consider taking the radiator off, plugging the bottom outlets and measuring how much water you can put into it, because I'm wondering if it's partially clogged.

If so, you'd need to give it a proper flush, there's videos online showing how.

[Cagey_Thoughts]

Thanks Grahamm... I'll do that... not long back from Limoges... shopping... although I did get to Italia-motos to look at a Moto Guzzi V86TT Tour... to replace my FJR1300... lol

[darrsi]

If it's being chucked out of the expansion tank then your waterways are clogged up, quite badly by the sounds of things. The fact you have coolant in the expansion tank when it's cool, but you've lost half a litre means the coolant doesn't have anywhere to go due to scaling in the pipes.

Time to get the Radflush out and give the system a good clean.

In this warm weather I would advise adding the Radflush to water in the system, after flushing out what's in there with a hose when your neighbours are not looking, and do the clean with the engine ticking over with the bike on the centre stand for about 10 to 15mins

Don't go out on the bike to warm it up with just water and Radflush in the system because plain water will boil as if it's in a kettle and the bike will overheat quickly when you're away from home, which you really don't want to happen.

---

Blowing air through the pipes will make no difference whatsoever, the waterways will have scaling inside them that can only be removed using a descaling liquid with hot water, as in Radflush and engine heat.
If you do it every couple of years, preferably in cooler conditions, then you won't get any issues and you will have a decent functioning airtight system.
And if all is working well then once the bike cools down the coolant will generally settle in the same spot each time with hardly any loss of fluid, unless you are in very hot conditions as you no doubt are in France, meaning you may need the occasional top up of coolant every now and then on inspection of the expansion tank level.
The level should be checked with the bike on the centre stand.