Best place to drain coolant on a m42?

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m7roadrunner
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Sat Mar 01, 2008 10:13 pm

As above lads, i want to flush me engine and rad out shortly. Is there a drain plug on the engine block itself? Using the rad plug only seems to drain the rad. I got bored with the search function after an hour :roll:
DanThe
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Sat Mar 01, 2008 10:22 pm

Get a hose on the job then, keep filling it up, running the engine then draining again.

Or you may be able to run clean water straight into the engine via the bottom rad hose.

Best flush additive is TFR = Traffic Film Remover
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m7roadrunner
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Sun Mar 02, 2008 8:44 pm

Cheers Dan, never heard of using traffic film remover tho. I have a bottle of rad flush for the job. I changed the thermostat recently and ended up using two different types of antifreeze. I'll get on the case during the week to save any damage.
scot
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Mon Mar 03, 2008 1:47 am

The coolant drain plug is just underneath the exhaust manifold. You might find that when you take the bolt out no coolant will come out as theres usually a layer of rust/crap you will need to poke with a sharp screwdriver till a gush of coolant hits you in the face! So be careful! Hope this helps :)
Dave_M3
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Mon Mar 03, 2008 2:12 am

I flushed my M42 out a few weeks ago by just putting the hose on it.
Then put in some antifreeze again.

Problem is though I think it still might have some air in it since it's getting hot while in traffic.
Has a new fan so that's ruled out winkeye

Would have though by using the constant filling technique would eliminate any trouble bleeding I might have if I just drained the whole lot.
M42 rightness above 6500rpm, nobody can hear you scream
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