Loss of coolant

[Northern Bongolow]

you dont have to remove the aircon to replace the heater matrix for the coolant system.
look at this diagram below and cutlasses pic you will see the spring clips that split the casing in half, then remove what you want then pop it back together.

i did one for bongo baz in a field at stourport, it did take a while cos you have to bleed it after.

warning,

its easier to take out the whole unit to do it so you can clean out the years of crap, catch the bits that you drop in the bottom (heater box spring clips fly) (body inside side panel clips fly) and you can get into the body to rust treat as this is one of the worst areas on a bongo to rust.

http://lushprojects.com/bongopartsmk2/c ... mgno=.html

[cutlass]

Northern Bongolow - sorry - I dont may do it..... my hand dont to invade in that place///////

[Roy748]

Good morning Northern bongolow.
Wow that has thrown a spanner in plans, I was all set to replace the entire heating matrix and have it regassed via my local garage, now you have me intrigued.
As my ac system is working fine it would make sense to only replace the heater aspect if possible. Based on what you say I think I will investigate this option more.
Thanks for the info..
Teenmal I apologise for doubting you, you were obviously correct in your thinking.

[Roy748]

Hello all.
Unfortunately my leak remains..
Monday this week with a break in the weather I got under the van and bypassed the rear heater matrix using copper piping. Topped up the header tank to mid level and started the van. All seemed fine, level dropped a little so topped up again, very small amount of bubbles returned initially to the header but then ceased, massaged a number of rubber hoses too. As this is a 2.0ltr version the bleeding process I believe is pretty simple. Left the van running for 30 minutes on the drive and coolant level settled mid way. Checked pressure in the header tank when engine turned off and all seemed fine, pressure but not excessive.
Today Friday, intended on fitting coolant alarm hence why I left it parked up with only a half full header tank, only the header tank was empty again.. looking around, under and over the van I cannot see any signs of leakage.
So again I topped it up with approx 600ml, massaged the pipes and started it again. Left it running for 30 mins constantly checking the header tank, no bubbles and no loss of coolant. After 30 minutes I drove it down the road and back, temperature gauge remained normal throughout.
I have checked the oil filler cap and dipstick and there are no signs of water.
Again checking over the vehicle I could see no leaks.
So now I ask, what am I missing? Should I buy some uv dye and run this through the system, some say KSeal but I would rather find the cause than hide it.
Any advice would be greatly appreciated.
Just to recap, the initial leak was evident due to coolant on the drive directly below the rear heater matrix.

[mikeonb4c]

Whatever you do DON'T use K-Seal. From what I've read it can clog your system and is unlikely anyway to mask the underlying problem for long. Its possible for coolant from pinhole leaks to evaporate without leaving things wet or dripping, when the engine is hot. Are you quite sure the level drop was not just a combination of trapped bubbles coming out plus the level drop that happens when the system cools. Do you have a low coolant alarm fitted, as that might help you keep going until the problem source gives itself away.

[Roy748]

Hello mike.
I thought I would leave it over night and check tomorrow. I am hoping it could be just former air escaping but has now settled and will remain static. Re K-seal I am of the mind to pass on using this so your thoughts confirmed my belief.
If it has dropped by tomorrow I will try uv dye.
I will be fitting the newly purchased coolant alarm.

[mikeonb4c]

Hello mike.
I thought I would leave it over night and check tomorrow. I am hoping it could be just former air escaping but has now settled and will remain static. Re K-seal I am of the mind to pass on using this so your thoughts confirmed my belief.
If it has dropped by tomorrow I will try uv dye.
I will be fitting the newly purchased coolant alarm.

Sounds good - keep us posted. At least the 2 litre petrol doesnt have quite the same issues with bleeding as diesel and v6 etc

[Northern Bongolow]

heres a pic of the system.

http://lushprojects.com/bongopartsmk2/c ... o=.html#45.

13-104t is to fill the system from its lowest point, pushing all the air out as it fills probably in the factory.

15-385 is a one way valve from the rad, might be worth checking.

this thread may help.


viewtopic.php?f=3&t=32444

[Roy748]

Just a quick update.
Well its been 5 days since I topped the header tank up and I am pleased to say the header tank coolant level appears unchanged. So it would appear the coolant level drop was due to trapped air slowly making its way out over night, even after running the vehicle for 25 mins the air remained trapped.
I am now going to fit the coolant alarm or else I will be constantly wanting to check the coolant level..

[Bob]

Well done.

Personaly I'd recommend a quality one, such as supplied by Haydn Alarms, although others are happy with the cheaper e bay jobbies.

I do like the fact it 'self tests' every time you start the motor.

[Roy748]

Hello Bob
It's the Haydn alarm I have purchased.

[Bob]

It's what I've got, and certainly saved the day a few years ago.

[mikeonb4c]

Hello Bob
It's the Haydn alarm I have purchased.

11 years from purchase, mine stills works perfectly - and its saved me more than once. In this case, you appear to get what you pay for (plus great customer support, should you need it)

[Bob]

I can also vouch for that.

Just today I received (foc) a replacement self tapping screw from Jo.

Alarm was fitted on import just over 10 years ago.

[Roy748]

Hello all
Sadly i am in need of more advice. Having topped up my header tank and left the van Idle for 2 weeks with no visible coolant loss we opted for a drive out last weekend. After 40 miles round trip, parked up the Bongo and checked the coolant level, even though I now have a Haydon coolant alarm fitted, and noticed a very slight drop in the level but nothing notable, thought this could still be trapped air escaping. Today after 5 days parked up I again checked the level and noticed the level sitting just above half way between max and min. Yet no leaks are evident on the drive.
So I wonder is the head gasket damaged, but I am of the opinion, well hoping not, as she starts and runs superb, no loss of power and no smokey exhaust. I checked the oil filler cap and it's as clean as a whistle, although I guess 30 minutes idling and 40 miles driven may not produce signs in the oil yet.
On the day I drove with an empty header tank I could still hear water sloshing around in the front heater matrix so water was in the system and the temperature gauge never rose past 11 o'clock which is normal. Also the radiator pipes were only warm to touch and full of water upon examination.
I am now hoping it's a leak somewhere else that is not visible but enough to drain the system over a few days. So on this assumption I am going to purchase a radiator pressure test kit, with a view to checking the system.
So what I am asking is how do I go about using the kit, I have a basic idea on how it works and watched a few YouTube videos but nothing on using it on a 2.0 ltr petrol 2001 bongo. As surely there is a specific procedure due to the header tank featuring.
Any advice would be greatly appreciated.