Small coolant loss, is this normal?

Technical questions and answers about the Mazda Bongo

Moderators: Doone, westonwarrior

bongo frenzee
Bongolier
Posts: 232
Joined: Fri Feb 19, 2010 9:14 pm
Location: Loughborough, Leics

Small coolant loss, is this normal?

Post by bongo frenzee » Sun Jun 12, 2011 10:24 pm

We've just had our Bongo a year now, and over the past couple of months the coolant alarm has 'muttered' a bit just at the start of a journey, when cornering. I had assumed this was due to the coolant being cold and/or the level changing as I drove round corners as the level looked fine on the flat and the alarm only sounded at the very start of a journey. Today however, the alarm went off as soon as the engine was switched on, and stayed on... I immediately switched the engine off and checked the coolant level, it was just down to the level of the alarm probe so not critically low, but low enough to make it sound.

I topped up with water (only needed about 100ml) and drove home without incident, but should I be concerned about what seems to be a small loss of coolant over potentially as long as 12 months? Is a small amount of coolant loss over time normal for Bongos? I've not seen any sign of leaks on the driveway etc.

Cheers for any advice.
Living for the weekends...

CUIDADO! VEICULO BONGO!
User avatar
Northern Bongolow
Supreme Being
Posts: 7549
Joined: Mon Mar 15, 2010 11:33 pm
Location: AKA Vanessa

Re: Small coolant loss, is this normal?

Post by Northern Bongolow » Sun Jun 12, 2011 10:41 pm

any water loss is a problem,may just be a small problem today,but tomorrow.
whats the recent history with the motor----had new rad last year etc,or a burst hose 6 months ago,all this may help us to help you.
User avatar
mikexgough
Supreme Being
Posts: 6158
Joined: Mon Sep 08, 2008 9:02 pm
Location: Cambridgeshire - where the all the Slodgers reside

Re: Small coolant loss, is this normal?

Post by mikexgough » Mon Jun 13, 2011 6:02 am

A small loss like that can occur over time, well known and documented in Japan that over a 5yr coolant cycle a header tank can fall to bottom with no physical loss...and that applies to all cars with sealed systems....... hot/cold cycles and evaporation is the cause of that loss.... I would suggest that it could be your problem but please check all your hoses and you radiator seams in the 1st instance....
Conversant with Bongo Top Pinion Oil Seals

Bongo owning Velotech Cycle Mechanic
User avatar
haydn callow
Supreme Being
Posts: 5716
Joined: Mon Jan 08, 2007 9:50 pm
Location: Somerset

Re: Small coolant loss, is this normal?

Post by haydn callow » Mon Jun 13, 2011 9:24 am

Make sure you top up to the FULL line on the header tank when cold...If you cannot see that line 'cos your tank is stained......put a "wooden dipstick" vertically down through the neck of the tank untill you touch the ledge inside....you should show a depth of coolant of about 1.5/2cms on the bottom of the stick...
http://www.coolantalarm.co.uk
Developer of the Mazda Bongo Coolant loss Alarm
Also BMW Clocks
bongo frenzee
Bongolier
Posts: 232
Joined: Fri Feb 19, 2010 9:14 pm
Location: Loughborough, Leics

Re: Small coolant loss, is this normal?

Post by bongo frenzee » Mon Jun 13, 2011 5:27 pm

Northern Bongolow wrote:any water loss is a problem,may just be a small problem today,but tomorrow.
whats the recent history with the motor----had new rad last year etc,or a burst hose 6 months ago,all this may help us to help you.
It's a new import, I'm the first UK owner and it was fully serviced on arrival with coolant flush/change, pressure test and proper bleeding. AFAIK all the parts are original.

It's a 1999 diesel if that helps.
Living for the weekends...

CUIDADO! VEICULO BONGO!
User avatar
Northern Bongolow
Supreme Being
Posts: 7549
Joined: Mon Mar 15, 2010 11:33 pm
Location: AKA Vanessa

Re: Small coolant loss, is this normal?

Post by Northern Bongolow » Tue Jun 14, 2011 3:17 am

pm sent.
User avatar
kev&caz
Bongonaut
Posts: 83
Joined: Tue Sep 09, 2008 8:42 pm
Location: Westmidlands

Re: Small coolant loss, is this normal?

Post by kev&caz » Tue Jun 14, 2011 7:16 am

Hi all long time no see. I have a slight water loss. Like you my alarm goes off occasionally. It has taken me ages but I have now found the leak this morning. It’s in the bleed tube it is getting worse as will yours. This is the only pipe I’ve not yet changed. But I will change it in the next day or so. I have found they are very prone to water loss and the water alarm has saved me count less times. I have been looking for the leak every time I stop for ages so I would recommend you keep looking you will find it & it will save you money in the long run.
User avatar
Cloughy
Bongonaut
Posts: 34
Joined: Wed Jun 27, 2007 8:41 pm
Location: Wirral

Re: Small coolant loss, is this normal?

Post by Cloughy » Tue Jun 14, 2011 9:41 am

Hi,

I had the same issue for 2 years, spent time looking for the leak used UV dye, checked all round when hot etc. found nothing.
I needed to add 100ml about every 3 months.
Eventually felt a very slight dampness on the underside of a jubilee clip on a hose leading from the rad, where it joined the a metal pipe.The garage inspected it, said the hose was fine but refitted and tightened the clip.
It has been fine since and the alarm hasn't sounded for a year.

Cloughy
User avatar
Alacrity
Tribal Elder
Posts: 630
Joined: Tue Jan 12, 2010 10:02 am
Location: Eastbourne, East Sussex

Re: Small coolant loss, is this normal?

Post by Alacrity » Tue Jun 14, 2011 11:12 am

Mine has always lost a little coolant over time, I have changed various hoses & clips for tiny weeps but she still looses a little, never a lot though. When I fill it I use a vacuum filler & it always pulls & holds a vacuum OK #-o . Work that one out.

Thinking about it as I write it points to the tank pressure cap doesn't it. :oops: :)
35+ years working with autogearboxes - all day every day......for my sins
steveyd
Bongolier
Posts: 168
Joined: Tue Mar 16, 2010 9:10 pm
Location: Wantage

Re: Small coolant loss, is this normal?

Post by steveyd » Tue Jun 14, 2011 11:23 am

Hi,

Mine loses about this amount too - I have replaced most of the system but I found the leak was where I had replaced the original constant pressure clips with a jubilee clip - new pipes will compress a bit further after a while meaning the jubilee clip is not as tight as it should be and hence a slow weep. If you have jubilee clips give them a feel and any that are damp nip them up a bit.

I dont have a drippy beed hose and I do want to change the pump - these (as someone said) can also be a cause for a slow loss. Could also be worth checking front and rear heater matrixes - the stubs can crack but they can also leak from the matrix itself - both mine went! (blanked off the rear one - actually makes the bleeding process a lot easier!)

cheers,

Steve
User avatar
Northern Bongolow
Supreme Being
Posts: 7549
Joined: Mon Mar 15, 2010 11:33 pm
Location: AKA Vanessa

Re: Small coolant loss, is this normal?

Post by Northern Bongolow » Tue Jun 14, 2011 12:43 pm

Alacrity wrote:Mine has always lost a little coolant over time, I have changed various hoses & clips for tiny weeps but she still looses a little, never a lot though. When I fill it I use a vacuum filler & it always pulls & holds a vacuum OK #-o . Work that one out.

Thinking about it as I write it points to the tank pressure cap doesn't it. :oops: :)
it doent really mean its the cap in my opinion, if you a vacuuming the system, you are pulling the hose to pipe seal together, if you use possitive pressure inside the system to test it, its trying to push the system apart so leaks can show easier, also the the system is only designed to hold about 1 pound in negative pressure,but is designed to hold 1.1 bar in positve pressure.

anyone with cap issues can look me up at the bash,as im doing cap testing (both poss and neg pressure) at the bash, with a small nominal charge all going to the bongo fury nominated charity.
User avatar
mikeonb4c
Supreme Being
Posts: 22810
Joined: Sun Nov 05, 2006 10:49 pm
Location: Living with Mango Bongo in the North West but with a tendency to roam

Re: Small coolant loss, is this normal?

Post by mikeonb4c » Tue Jun 14, 2011 1:05 pm

bongo frenzee wrote:We've just had our Bongo a year now, and over the past couple of months the coolant alarm has 'muttered' a bit just at the start of a journey, when cornering. I had assumed this was due to the coolant being cold and/or the level changing as I drove round corners as the level looked fine on the flat and the alarm only sounded at the very start of a journey. Today however, the alarm went off as soon as the engine was switched on, and stayed on... I immediately switched the engine off and checked the coolant level, it was just down to the level of the alarm probe so not critically low, but low enough to make it sound.

I topped up with water (only needed about 100ml) and drove home without incident, but should I be concerned about what seems to be a small loss of coolant over potentially as long as 12 months? Is a small amount of coolant loss over time normal for Bongos? I've not seen any sign of leaks on the driveway etc.

Cheers for any advice.
The single most important thing is that you have had the good sense to fit a low coolant alarm. If only more people thoght to do it before rather than after etc.

Mine mysterously needs a little top up now and then, at weirdly spaced intervals (can be a year or more, and only a small amount needed). I don't worry about it at all (though I do alwyas check the hoses etc. when I have the engine hatches up).
I Bongo, therefore I am...
Bongoing, BonGoing, BonGone
User avatar
mikeonb4c
Supreme Being
Posts: 22810
Joined: Sun Nov 05, 2006 10:49 pm
Location: Living with Mango Bongo in the North West but with a tendency to roam

Re: Small coolant loss, is this normal?

Post by mikeonb4c » Tue Jun 14, 2011 1:06 pm

Northern Bongolow wrote:any water loss is a problem,may just be a small problem today,but tomorrow.
whats the recent history with the motor----had new rad last year etc,or a burst hose 6 months ago,all this may help us to help you.
"Maybe not today, maybe not tomorrow, but eventually, and for the rest of your life"
Image
:lol: :lol: :lol:
I Bongo, therefore I am...
Bongoing, BonGoing, BonGone
User avatar
Triple/R
Supreme Being
Posts: 1395
Joined: Sat Nov 15, 2008 2:06 pm
Location: Derby/Notts border

Re: Small coolant loss, is this normal?

Post by Triple/R » Tue Jun 14, 2011 3:42 pm

I reckon if you've checked recently & level was ok,you've got a leak if it's all of a sudden dropped to the probe level~~as you say you've heard the alarm muttering a bit which they do in cold weather~keep an eye on your pipes etc;

I was loosing water albeit not a lot but having to top up regular for months with no sign of water on drive or pinholes in the pipes & found eventually it was the water pump.
Regards Ray & Christine

It's only easy when you know the answer!!!!!!!!!!
bigdaddycain
Supreme Being
Posts: 10637
Joined: Fri May 13, 2005 11:58 am
Location: Ince Lancs

Re: Small coolant loss, is this normal?

Post by bigdaddycain » Tue Jun 14, 2011 10:11 pm

mikexgough wrote:A small loss like that can occur over time, well known and documented in Japan that over a 5yr coolant cycle a header tank can fall to bottom with no physical loss...and that applies to all cars with sealed systems....... hot/cold cycles and evaporation is the cause of that loss.... I would suggest that it could be your problem but please check all your hoses and you radiator seams in the 1st instance....
Same here mike... mine needs about a "cupful" every six months or so... No apparent leaks.
ビッグダディケイン RIP Big Bank Hank (Imp the Dimp) 1957-2014