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Tiny metal flakes in coolant
Posted: Wed Sep 19, 2012 6:15 pm
by Longusta
Hi all. Picked up my bono last night. I got it for a good price knowing that it needed some
Bits doing to it. It hasn't been used much over the last year so I know it needs a good service. I've checked the coolant and it's rusty colour and has tiny metal flakes in it ( looks like a copper colour) im pretty sure the thermostat is faulty or has been removed as it takes ages for the temp gauge to register. Is this likely to cause the problem or am I looking at a head gasket? Or do the internals of the radiator deteriorate over time? The previous owner has said its never over heated, but I can only take his word for that. it has a high temperature and a low coolant alarm on it. Thanks in advance
Re: Tiny metal flakes in coolant
Posted: Wed Sep 19, 2012 7:19 pm
by francophile1947
Sounds like a leak sealant has been put in the coolant, presumably because the coolant was being used. Bongos don't normally take long to heat up, so thermostat is either faulty or removed. If the latter, it's a common modification made to avoid overheating

Re: Tiny metal flakes in coolant
Posted: Wed Sep 19, 2012 7:53 pm
by mikeWalsall
Sounds like someone as added k-seal to the coolant (maybe to seal the head gasket ??) ..
http://www.k-seal.co.uk/?gclid=CM-y_fan ... tAod9CcA_w
Re: Tiny metal flakes in coolant
Posted: Wed Sep 19, 2012 8:04 pm
by Longusta
Cheers. Think I'll have to get the system pressure tested and go from there. If the head gaskets gone will the coolant level go do even if I'm not driving the bongo? I haven't noticed any leaks or the coolant level dropping but have only had it 24 hours and not really driven it.
Re: Tiny metal flakes in coolant
Posted: Wed Sep 19, 2012 8:33 pm
by Velocette
Hmmmm I can't remember the exact timings, but I found tiny flakes in mine between buying it second hand and the head gasket going when I had had it about nine months.
My radiator was diagnosed as blocked when the head went. I wasn't concerned about the flakes at the time, I had had a system flush and coolant change and assumed they had been stirred up by the flushing. Whether they were connected to the later failure is impossible to say.
Re: Tiny metal flakes in coolant
Posted: Thu Sep 20, 2012 7:05 am
by mikexgough
Kseal will leave trace copper "flakes" in the coolant but doesn't discolour it brown as you mention.
It could have been put in as a prevention like the trade do to Punto's and K series engines as they are prone to Head Gasket failure, Punto's as regular as 40,000 miles. I have seen it and if it wasn't for trace flakes then you would never know it had Kseal in it. Trade colleagues put it in to save claims for HGF post refitting as it works....
As for temperature registering.... kseal changes nothing so I am told, everything works as normal inc fan switches, all I can suggest is a missing thermostat...or maybe a gauge sender issue.
Sounds like a good flush and replace thermostat etc before drawing any conclusions...... at least if you have fully flushed before you replace coolant, should the head or gasket be duff you can always drop the coolant and save it... for post repair refill
Re: Tiny metal flakes in coolant
Posted: Thu Sep 20, 2012 7:57 am
by wonkanoby
browns usually rust from all the steel pipes
usually as sign its been run without anti freeze at some time
Re: Tiny metal flakes in coolant
Posted: Thu Sep 20, 2012 8:20 am
by haydn callow
Dark brown coolant is very often caused by a overheationg event (coolant boils)...this causes all the years of sediment from the "depths" of the system to be disturbed and circulate round the system..
Re: Tiny metal flakes in coolant
Posted: Thu Sep 20, 2012 9:26 am
by teenmal
haydn callow wrote:Dark brown coolant is very often caused by a overheationg event (coolant boils)...this causes all the years of sediment from the "depths" of the system to be disturbed and circulate round the system..
99% of time that is what causes the Dark brown (Rust)colouring of the coolant in old vehicles and usualy leaves a stain where it has leaked or overflowed..
Re: Tiny metal flakes in coolant
Posted: Fri Sep 21, 2012 1:39 pm
by mikexgough
wonkanoby wrote:browns usually rust from all the steel pipes
usually as sign its been run without anti freeze at some time
Yep ..... agree plus vehicles when they stand for a long period, which Jap homeland vehicles do.
They don't use cars etc like we have to, they have proper & cheap public transport
Re: Tiny metal flakes in coolant
Posted: Sat Sep 22, 2012 4:44 am
by Longusta
Cheers for all the info, the bongo had been stood there for about 6months or do before I brought it. Got myself a new thermostat and some system flush. Ganna give it a go over the weekend
Re: Tiny metal flakes in coolant
Posted: Sat Sep 22, 2012 6:12 am
by Titan1995
Hope you bought a genuine thermostat....the pattern ones just don't make the grade.
Are you also aware of the bleeding procedure of the Bongo....assuming that you have a diesel.
Re: Tiny metal flakes in coolant
Posted: Sat Sep 22, 2012 9:28 am
by wonkanoby
look over all the hoses
but if its a diesel the first ones to go are
top main hose to block front under drivers seat
and the one comes out of engine and runs over starter motor
if they are original i would replace as a matter of prudence
Re: Tiny metal flakes in coolant
Posted: Sat Sep 22, 2012 8:31 pm
by Longusta
Decided against giving it ago as didn't have any help, and judging by the videos on you tube bet to have 2/3 people. Think I might get it booked in to discount trucks next week as they seem to highly recommended on here, and get the experts to give it the once over. Thanks for all
The advice
Re: Tiny metal flakes in coolant
Posted: Sat Sep 22, 2012 9:18 pm
by psquiddy
Titan1995 wrote:Hope you bought a genuine thermostat....the pattern ones just don't make the grade.
Are you also aware of the bleeding procedure of the Bongo....assuming that you have a diesel.
Isnt the bleeding proceedure the same for all Bongos? (Mine is a 2.0 petrol and I am planning on doing a coolant change before winter sets in)