Cooling system/ Bleeding

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Sukaber
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Cooling system/ Bleeding

Post by Sukaber » Fri Oct 09, 2015 9:07 pm

Question 1: Iknow there is a lot of talk about how hard it is to bleed a Bongo, but is it particularly difficult if the garage has a vacume thingy to do it please?

Question 2: the garage is saying that my coolant pipes are 'crunchy' Is it worth changing just the main ones or should I go whole hig and xhange them all... Any ideas how much each would cost to do?

Thanks in advance.
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Northern Bongolow
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Re: Cooling system/ Bleeding

Post by Northern Bongolow » Fri Oct 09, 2015 9:25 pm

as the bongo has many coolant pipes set up in loops a vac fill may pull coolant in (the easy way) or via the largest pipe or the best flowing route. this method may not withdraw ALL the air from the system, for this reason i would not use one on a bongo.

some have done it, some have done it well, but the how would you know if its done right, the only way is when it doesnt boil up, not very safe or accurate.

full set of gen mazda rubber pipes are about £300 if i remember right.
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Diplomat
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Re: Cooling system/ Bleeding

Post by Diplomat » Fri Oct 09, 2015 9:28 pm

I wonder how often one can crunch 'crunchy' hoses?

Twice, perhaps, before replacing them?


Frank
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They flew, I took up naturism
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Northern Bongolow
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Re: Cooling system/ Bleeding

Post by Northern Bongolow » Sat Oct 10, 2015 8:32 pm

crunchy hoses is not usually the pipe itself its the solidified rusty gunge that is heated on to the inside of the hoses this forms a nice crust. it usually means the coolant is long since useful and could mean a lot worse.
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mikeonb4c
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Re: Cooling system/ Bleeding

Post by mikeonb4c » Sat Oct 10, 2015 8:54 pm

Northern Bongolow wrote:crunchy hoses is not usually the pipe itself its the solidified rusty gunge that is heated on to the inside of the hoses this forms a nice crust. it usually means the coolant is long since useful and could mean a lot worse.
Indeed. If there's crunch in the hoses, it may be that there's the same crunchy crud in places like radiator matrices, reducing their efficiency.
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Diplomat
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Re: Cooling system/ Bleeding

Post by Diplomat » Sun Oct 11, 2015 10:27 am

In the light of these explanations, I had better modify my comment to:

'Once and then clear out all the muck that has been released'!


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mikeonb4c
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Re: Cooling system/ Bleeding

Post by mikeonb4c » Sun Oct 11, 2015 10:52 am

Diplomat wrote:In the light of these explanations, I had better modify my comment to:

'Once and then clear out all the muck that has been released'!


Frank
Indeed Frank, and it has to be assumed also that crud/scale has built up in the radiator cores. Given that the Bongo main radiator becomes very liable to developing a leak anyway (where plastic meets metal) as it gets old (mine leaked at around 17yrs age), crunchy houses might suggest a (decent, not cheap pattern) new radiator could be a good thing all round for the general health of the engine. I recall Adrian at Japandirect, who does my Bongo, showing me a Bongo where he'd even had to fit a new heater radiator due to severe crudding of the system. The top hose felt like concrete. I think a little crunchiness may not be panic worthy though.
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Northern Bongolow
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Re: Cooling system/ Bleeding

Post by Northern Bongolow » Sun Oct 11, 2015 8:27 pm

the rear heater pipes, the ones on the underside near the back wheel are usually good indicators of this crunchiness as the heavier solids flow around the system until they reach the lowest point in the system where there is a partial restriction (the rear heater matrix), then they build up and get cooked solid.
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