Been busy this weekend and I have some coolant observations.

[francophile1947]

Good for you

[waycar8]

Glad your bongos now up to scratch Nick, how much was the new header tank from mazda btw, (I recon your going to get that question asked alot)

[francophile1947]

Sit down, £113 inc. vat

[waycar8]

, but I bet theres a few people that will go and buy it too just so theres is cleaner than everyone elses.

Mines not that bad but ive seen some thats pure brown and you cant see anything at all

[mikeonb4c]

An excellent post Nick - I hope it gets widely read. I'm interested to see you fitted a capillary type temp gauge - The Great Pretender would approve

[Simon Jones]

Nick - some good observations there. Have you got a picture, or any details on the capillary temp gauge? This sounds like an interesting idea.

[Alison01326]

The header tank had to come from Mazda but only took 2 days

Hopefully I don't need one (long story but possibly watch this space) but did you get it through your local Mazda dealer, and was it an actual Bongo one or is the Bongo header tank the same as is fitted in another vehicle?

Have already noted the price but as mine is lovely and clean, if I have to replace it, I don't want one that looks like I imagine the inside of an old teapot looks for £20 from a breakers.

[The Great Pretender]

I got the gauge from a chap on Ebay, type in Capillary Water temp gauge and he will come up, £25 with the post. It's a TIM product and made in England!!!

I am a bit crap with photos etc. but will give it a try.

You do need facilities to do what I did or a mate with the same. I turned a bit of thick walled steel tube so it had beads on each end, turned up a 1" dia boss which I threaded 5/8 UNF, tigged the boss on to the tube. I then split the top hose just after it turns 90 deg where it comes out of the head and inserted the tube and boss assembly there. The gauge is mounted in the top drivers side corner of the cubby hole in front of the gear lever. The capillary boss / pipe passes through the grommet where the gear selector cable passes in to the engine bay.

Nice to have someone else trying to understand the wonder of the Bongo cooling system.
I did similar at the top hose but also made a thermostat housing there. I never did any temp readings before the mod, yours are intresting.
Here is my stat housing with take off to bar gauge for reading pressure.



Instead of capillary I used this little thermistor.