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Discussion Starter #1
Hi all,

is there a best practice for bleeding the cooling system on a 155 TS engine, i.e. getting rid of air locks in it? Do I first heat up the engine and then undo the bleed screw on the radiator? Or does the screw have to come out first and then I start heating the engine? And do I need to keep the expansion tank cap off during the procedure? And does the squeezing of the hoses help?

many thanks
 
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When you drain the system, make sure you leave the heater set on full heat to make sure all the water from the heater box drains as well, same for when you fill the system as well, take the bleed screw out of the rad, fill the system up via the header tank to the top of the rad, put the bleed screw back in, and fill the system up to the max on the header tank. Run the engine with the header cap off to get most of the air out. Let the engine cool, top up the header tank, screw cap back on. Keep an eye on the water level for the next few days as there is bound to be a little more air come out.

Steve
 

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Discussion Starter #3
thanks for the advice Steve, but it doesn't seem to work. I get liquid come out through the rad bleed screw on a cold engine. Thing is that I got air into the system when changing the thermostat and I didn't drain the sytem for that. After the change I simply topped up the system with about a litre of cooling liquid that had been spilled during the change. After the repairs I'm not getting any hot air from the heater. Should I drain the system completely and then fill it up again? Or is there an easier way?
 

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I would try squeezing the top radiator hose for a while and that should push the water round and get a big airlock out :) works for me :D
 
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Is the engine definately getting hot? Wait for the fan to come on to be sure.

Steve explained the exact way to do the operation....always worked for me and no need to worry about emptying the system either.

wrinx
 

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Discussion Starter #6
Problem solved. Apparently I didn't heat up the engine enough the first time and the thermosat didn't open. So then I waited till the temp reached about 90 degrees and did some squeezing of the top rad hose with the header tank cap off. Also kept the cap off until the engine cooled.
Thanks everyone.
 
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