How to bleed coolant system after an engine rebuild :?:

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gooner1
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Post Sun Mar 04, 2012 12:56 pm

As above, with new rings ,shells, etc not bedded in.
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Andyboy
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Post Sun Mar 04, 2012 3:14 pm

Not too hard. Bleed screw out and disconnect top rad hose from the rad to avoid air locks. Fill it nioce and slow, a litre at a time starting with anti freeze. On a bone dry engine it's easier still to fill with the thermostat and cover off and as soon as the coolant starts to build up in the stat housing, refit the stat, add another litre or so until coolant starts to dribble from the bleed screw - fit the bleed screw and that's it. Set heater to hot, fire it up and run for 10 mins at a steady 2000 rpm without letting the revs drop - it's essential to do this if you've fitted a new cam in order to bed the lobes and followers in properly. As soon as the heater starts to blow hot, it's bled.
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gooner1
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Post Sun Mar 04, 2012 3:19 pm

Cheers Andy. :thumb:
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kingludba
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Post Fri Mar 09, 2012 12:54 am

Andyboy wrote:Not too hard. Bleed screw out and disconnect top rad hose from the rad to avoid air locks. Fill it nioce and slow, a litre at a time starting with anti freeze. On a bone dry engine it's easier still to fill with the thermostat and cover off and as soon as the coolant starts to build up in the stat housing, refit the stat, add another litre or so until coolant starts to dribble from the bleed screw - fit the bleed screw and that's it. Set heater to hot, fire it up and run for 10 mins at a steady 2000 rpm without letting the revs drop - it's essential to do this if you've fitted a new cam in order to bed the lobes and followers in properly. As soon as the heater starts to blow hot, it's bled.
just the answer I was looking for too!

:D
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