Bleeding nightmare

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BongoBunny
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Bleeding nightmare

Post by BongoBunny » Wed Jun 26, 2019 5:41 pm

Hello I hope someone can help me. I am at the end of my piece of string. I have followed the 3 sets of instructions on the fact sheet for bleeding the cooling system and I can’t get the bottom hose warm (thermostat open) before the water in the funnel attached to the bleed pipe starts to boil. I have given each version 1-2 hours. I have put on a skimmed and pressure tested head, new water pump and new thermostat. There are no leaks.
Has anyone come across this before?
Bob
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Re: Bleeding nightmare

Post by Bob » Wed Jun 26, 2019 5:49 pm

Oh dear. :(

Take a look at these three videos:

https://m.youtube.com/watch?v=jRAKOSxgbKo
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g8dhe
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Re: Bleeding nightmare

Post by g8dhe » Wed Jun 26, 2019 8:32 pm

Did you test the thermostat before fitting ? I seem to recall at least one person who had a new but duff thermostat supplied ?
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mikeonb4c
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Re: Bleeding nightmare

Post by mikeonb4c » Wed Jun 26, 2019 10:59 pm

Are you confident the radiator isnt old and blocked?
teenmal
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Re: Bleeding nightmare

Post by teenmal » Thu Jun 27, 2019 4:04 pm

BongoBunny wrote: Wed Jun 26, 2019 5:41 pm Hello I hope someone can help me. I am at the end of my piece of string. I have followed the 3 sets of instructions on the fact sheet for bleeding the cooling system and I can’t get the bottom hose warm (thermostat open) before the water in the funnel attached to the bleed pipe starts to boil. I have given each version 1-2 hours. I have put on a skimmed and pressure tested head, new water pump and new thermostat. There are no leaks.
Has anyone come across this before?
As a wee bit more information.....

What was wrong that you had to have the head skimmed,
Is this the original head or a replacement.?
BongoBunny
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Re: Bleeding nightmare

Post by BongoBunny » Thu Jun 27, 2019 6:49 pm

Hi Bob, Geoff, Mike and Teenmal.
Thanks for your responses, I have had a new radiator in the last 6 months so I hope it’s not that. Following the tip about the ‘stat I have done a very bad thing and taken it out, replacing just the rubber seal. I forgot to mention I’m about 300 miles from home so my options are limited, I will test the ‘stat when I get home and mention to the supplier when I send my old head back (exchange £255 quid so you probably know who they are). Anyway I bled the system without thermostat following the videos and i no longer have to stop every 4 miles. Thanks for your help and I know running without a thermostat is bad but is there anything I should look out for? I will def test any thermostat I replace. Thanks again to you all.
Bob
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Re: Bleeding nightmare

Post by Bob » Thu Jun 27, 2019 6:53 pm

Did it bleed ok once the stat was removed?

Please don't drive it if you haven't bled it. :wink:
BongoBunny
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Re: Bleeding nightmare

Post by BongoBunny » Fri Jun 28, 2019 7:03 am

Sorry Teenmal, I missed your question, it was a cracked cylinder head (probably) which was pressurising the cooling system after a history of cooling problems going back a few years.

Drove about 60 miles yesterday with no overheating problems and dipped the coolant level and it was exactly on full this morning.

I have no way of expressing the relief I feel.
BongoBunny
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Re: Bleeding nightmare

Post by BongoBunny » Mon Jul 01, 2019 7:37 am

Bob - yes definitely bled and it worked as per the videos recommended. :)
Just a quick final note to readers to say that while thermostat removal has worked as a ‘get you home’ or in this case ‘get you to finish your North Wales tour holiday’ even in the middle of June the van runs a bit cold which probably affects engine wear and fuel economy and I’m sure if it was in the colder months would render the heater useless.
Thanks again Bongo folk.
Bob
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Re: Bleeding nightmare

Post by Bob » Mon Jul 01, 2019 9:26 am

Well done.

You've pretty much summed up why the 'stat is there. 8)
Rocky Road
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Re: Bleeding nightmare

Post by Rocky Road » Wed Jul 03, 2019 8:37 pm

Check EGR cooler is not leaking internally (exhaust gas feeding into coolant)
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