Why does the water level in my header tank increase?

[Sans Bateau]

Depends entirely on the installation. Many calorifiers are higher than the engine. On my motor sailer by a couple of feet. Conversely, on my VW van the top of the radiator, in the front of the vehicle, was higher than both the header tank and the heater matrix.

I did say 'usually'.

 

[Heckler]

Or soft solder coaxed by baker's fluid; the VP matrix that I've seen was a crappy thing with the tubes crimped into the endplate but not fully swaged, it's no surprise they leak. For £800 I expect a brazed assembly, not this halfbuilt nonsense.

+1,
if its swaged, a good candidate for silver soldering,
stu

 

[pvb]

The matrix on my 2003T heat exchanger appeared to have been dip-soldered after assembly. It's 22 years old - maybe more recent ones are different.

 

[whiteoaks7]

Latest update - newest symptom

After a gentle run yesterday the water level remained pretty much unchanged but the header tank this morning now has particles of something black in it. They are heavy and readily sink but don't seem to be metallic, more like ground rubber. questions: what are they (of course) and where from (no impellor in the closed system is there?).

The only flow through the header tank comes from the bleed (?) tube that runs from the thermostat housing. I recently unclogged this and noticed then that the result was a flow through the header, now I'm wondering if someone had blocked it for a reason though I can't immediately see the relevance to my problem.

I have a friend who recently sold his boat because, he said, he couldn't deal with the constant low level of anxiety - I'm beginning to see what he meant!!

David Berry

 

[pvb]

The only flow through the header tank comes from the bleed (?) tube that runs from the thermostat housing. I recently unclogged this and noticed then that the result was a flow through the header, now I'm wondering if someone had blocked it for a reason though I can't immediately see the relevance to my problem.

The outlet from the thermostat housing to the header tank is meant to have a small restriction in it, although obviously water has to be able to flow through it.

After a gentle run yesterday the water level remained pretty much unchanged but the header tank this morning now has particles of something black in it. They are heavy and readily sink but don't seem to be metallic, more like ground rubber. questions: what are they (of course) and where from (no impellor in the closed system is there?).

The impellor in the cooling system is metal. It's possible that a pipe or rubber seal is deteriorating and dropping bits of rubber in to the coolant. However, the coolant should be clean - when was it last replaced?

 

[Carmel2]

Your 2. I worked on one like this two weeks ago, but that coolant system 'made' water all the time. Domestic water pressure is normally a good deal higher than coolant pressure, so it makes sense. Watch upcoming PBO!.

I can testify to this because it was mine, and it works fine now!

Thanks again Vyv, when does our engine and calorifier have their 15 mins of fame in PBO?

 

[whiteoaks7]

I changed the oil cooler in May so every drop of coolant (I think) was removed then. I didn't flush everything through though and I'm wondering now if I simply stirred something up when it was refilled.

Doesn't explain the original problem of level changes though. In fact the whole thing seems to be a set of random events with symptoms changing on a daily basis. Time to think up some tests but I want to be closer to base before I start stressing things.

David Berry