What could cause this overheating. Water pump failure?

[Tony x]

Hi mikeonb4c
Yes. I have always paid attention to the cooling system but the Bongo gets a lot of use and it might be fatigue.
When we first got the Bongo the engine ran hot.
I couldn't believe it. A nice TM2 but the previous owner had disconnected the warning led and buzzer and didn't tell me. We sorted it all out (thanks again Haydn for the parts and help) including a good bleed that got the engine running at the correct temperature but I did wonder how much the head had been stressed. This was all about 4 1/2 years ago.
Cheers. Tony

[Tony x]

It's now fixed☺
But it needed a new head (cheers Allans at Plymouth)
The head was cracked at no' 4 cylinder
Tony

[Northern Bongolow]

bummer, thats a first for me though, never heard of a cracked one on cylinder 4. .

was it parked regularly nose down on the drive.???.

[Tony x]

Hi.
Yes. It was parked regularly nose down on the drive. The drive is a fairly shallow angle. About 7" under the front wheels makes it level.

[Northern Bongolow]

uummmm. (scratches head). the engine when parked on level ground will be slightly rear end down to lign up the prop etc, so if parked up level when warm or been ran for a while then left to cool down overnight any air sucked in to the head should go to the front of the head towards the top hose outlet, this may then be shoved out when the engine is started up again in the morning saving the head. in your case any trapped air may be lodged towards the back of the head so on start up theres little coolant.
this doesnt really explain why most go on cylinder 2 or 3 though, but i think its where the turbo is mounted on the exhaust manifold that explains this. maybe.

[mikeonb4c]

It's now fixed☺
But it needed a new head (cheers Allans at Plymouth)
The head was cracked at no' 4 cylinder
Tony

Glad its sorted Tony (and should be properly with Allans handling it) and hopefully you'll now have a healthy Bongo for some time to come.

P.S. Sorry i didn't reply to your earlier post - BF forum mustn't have listed it under new posts etc

[Tony x]

Hi
Yes - hopefully we will now get many more trouble free miles out of our Bongo.
It's the first major problem we've had over 8 years of owning a couple of Bongo's, the only other issues being an alternator and starter motor relay contacts - both relatively cheap and easy to sort.
I'm told the cylinder head we now have fitted is thicker around the valve area where they can crack.
I'd like to thank everyone for their help with this issue
Cheers
Tony