Is there an easy way to bleed the 2.5 diesel cooling system ?

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BongoBongo123
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Is there an easy way to bleed the 2.5 diesel cooling system ?

Post by BongoBongo123 » Mon May 04, 2026 1:53 pm

One of the constant fears I have carried as a long time Bongo owner is the post refill coolant bleed.

If you lose coolant is one thing (trace leak / replace pipes /rad etc.) and I keep to the 5 year schedule for refreshing the coolant to
keep the pipes in good shape and reduce corrosion risk. I am not averse to getting a pro to do it, as I do. However my pro is not exactly nearby.
I tolerate a drive and let the pro do his thing. However one cannot always rely on the pro being there forever and there comes a time when
one must attempt to learn for themselves.

Espcially if for example the radiator goes or an easy pipe goes. I have to spend big money on just getting the undriveable Bongo on low loader to said pro.

I kindly request any easy method for drain, refill and most importantly bleed of the system.

Even a written guide from those who know would be generous.

Thanks in advance.

Edit :I will start the thread off, this Youtube video does not seem too complex, but the video is slightly disjointed.

https://www.youtube.com/watch?v=6Jpa6yYGDtk
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BongoBongo123
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Re: Is there an easy way to bleed the 2.5 diesel cooling system ?

Post by BongoBongo123 » Mon May 04, 2026 2:44 pm

Here are the original bleed videos which I am going to watch and take notes again when I have time.

Parts 1-3

https://www.youtube.com/watch?v=jRAKOSxgbKo

https://www.youtube.com/watch?v=JUndta6MnFc

https://www.youtube.com/watch?v=DuGFnKxd4Wc

Maybe this is not as scary as one thinks afterall.

If anyone can maybe make comment of the things you absolutely must do and check that would be good for all.

I know there are some Bongo Master Tech's on here !
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g8dhe
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Re: Is there an easy way to bleed the 2.5 diesel cooling system ?

Post by g8dhe » Mon May 04, 2026 5:35 pm

There is a thread here for some more ideas viewtopic.php?p=659231#p659231
One thing I have noticed is that not all diesel Bongo's seem to have the same problem, I do wonder about the quality of coolant water used and perhaps furring up of the internal pipes with chalk deposits over time, hence the apparent variation in problems found ?
Geoff
2001 Aero V6, AFT, full side conversion.
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BongoBongo123
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Re: Is there an easy way to bleed the 2.5 diesel cooling system ?

Post by BongoBongo123 » Tue May 05, 2026 8:10 pm

Oh you mean the old pipe stalactites and stalamites g8dhe ? :lol:

You might be right and thanks for the link will check it out.

Super videos from Ian, Haydn and Missfixit70 - that is the long and comprehensive wya to do it. Half the job is watching them videos with your helper a few times I reckon get them in the brain properly with written notes (which i just did and put them in my Bongo folder). And having all your ducks in a row with the coolant mix, well fitting funnel, header tank measuring stick and heavy duty gloves for the funnel holder.

The bleed is the thorn in the side of the Bongo owner rather.
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