Loss of water from expansion tank - advice wanted

[Simon Jones]

I've had a diesel specialist take a look, and both he & the chap who has been helping me have concluded it is the block that is at fault. The head was pressure tested to 60psi & resurfaced. If there was a tiny crack in the head that expanded when hot, then that wouldn't explain why the problem occurs as soon as the engine fires up. So that tends to exclude the head. Talking to another member who had the same symptoms, he has suggested to go straight to the replacement engine, rather than throw money away on another head.

I've had a few quotes for reconditioned engines which vary from £1500 to £2100, but I've heard a few horror stories about dodgy garages, or engines that fail shortly after fitting. I'm in two minds about doing it myself, or paying the premium for someone else to do it for me and provide some form of warranty.

With regard to a chemical goo to plug the hole, I think I'd be very sceptical of it being able to withstand the higher compression ratio in a diesel engine. As much as I wish to avoid spending big bucks on a new engine, I think I'd always we worried about when the 'patch' might fail.

[The Great Pretender]

I've had a diesel specialist take a look, and both he & the chap who has been helping me have concluded it is the block that is at fault. The head was pressure tested to 60psi & resurfaced. If there was a tiny crack in the head that expanded when hot, then that wouldn't explain why the problem occurs as soon as the engine fires up. So that tends to exclude the head. Talking to another member who had the same symptoms, he has suggested to go straight to the replacement engine, rather than throw money away on another head.

I've had a few quotes for reconditioned engines which vary from £1500 to £2100, but I've heard a few horror stories about dodgy garages, or engines that fail shortly after fitting. I'm in two minds about doing it myself, or paying the premium for someone else to do it for me and provide some form of warranty.

With regard to a chemical goo to plug the hole, I think I'd be very sceptical of it being able to withstand the higher compression ratio in a diesel engine. As much as I wish to avoid spending big bucks on a new engine, I think I'd always we worried about when the 'patch' might fail.

Forgive me for not reading all the posts but if you fit a new engine and still find the problem. Are you shure the turbo isnt the problem?

[Simon Jones]

I did say I was going to by-pass it, but have not tried it yet. The steam coming out the bleed pipe has a definate 'pulse' to it which would seem consistant to the pressure being from one cylinder, rather than a steady blow from the turbo. I will give it a go tomorrow evening as my final resort.

[The Great Pretender]

I did say I was going to by-pass it, but have not tried it yet. The steam coming out the bleed pipe has a definate 'pulse' to it which would seem consistant to the pressure being from one cylinder, rather than a steady blow from the turbo. I will give it a go tomorrow evening as my final resort.

The pulse if related to engine it would need to match revs, does it?

[maxheadroom]

How about trying this stuff.....

http://www.racerindustries.com/store/in ... cts_id=263

I hope you get sorted soon.

[Simon Jones]

Just to give you an update on the current situation:

Had the head pressure tested again - no probs found, although one core plug was changed as it was starting to leak. Then gave the block a good going over with fine emery paper fixed to 8" square marble block which takes off any high spots & shows any low areas. After I'd got a nice even finish all over, I fitted new gasket using Wellseal compound, torqued it all down & reverse flushed the whole system. Fired it all up & bled the system - lots of air, but none of the bubbles & 'spurting' that I had before. I fitted an extra hose to the expansion tank overflow pipe & fed it up thru the top of the bonnet - that way I could see if it was loosing any water whilst I was driving. I took it for a fairly cautious drive round the area with no problems. So far, have driven it for about 25 miles without any problems, so I am quietly confident that all is well.

I plan to take it down to Bellhill Garage so Tom or Keith can take a look, but hopefully my cooling woes are over for now (he says, touching very large piece if wood ).

I've fitted a Haydn alarm which will warn of low coolant, but I will make a similar alarm to monitor the overflow pipe in case the level starts to rise again. Then I think I'll get a Masons alarm & possibly some form of LCD gauge to monitor the head temperature. I'm going to be very paranoid from now on!

Thanks to everyone who has provided hints & ideas to assist with the problem. Hopefully I can pass on some of what I've learned to other members.

[missfixit70]

Fingers crossed for you Simon Let's hope you've cracked it

[Aethelric]

Fingers crossed for you Simon Let's hope you've cracked it

Hope you really meant "fixed it"

[Simon Jones]

yes - crack is not a word you want to hear when you've got over-heating problems.

[erifis]

Just been roughly reading this thread. I had a similar water loss problem, anyway to cut a long story short, have you checked the water pump.

I was loosing water but could never find any sign of it under the bongo, it would loose water over night. Check filler tank on a morn and it was low, top up, drive to work, come home check level fine. Wake up next day check and it would be empty again.

It turned out to be the water pump, on the cold nights the seal was retracting and dripping enough water out to empty the header tank. I never saw the water in the morning as it was being caught on the sump tray.

For your info, before I worked out it was the water pump, it cost me a new rad, a new cylinder head (cracked in 3 places due to a friend doing a long run in it over a couple of days and not following my advice of filling up the header tank, idiot). The leak was causing an air cavitation in the cylinder head.

I only discovered the water pump was the cause when it was still using water after I changed the cylinder head.

After I changed the water pump, I have never lost a drop of water since.

My advice now is always start at the water pump if there is no other obvious problem.

cheers,hope this helps, apologies if you have already done this, long thread.

[mikeonb4c]

Just been roughly reading this thread. I had a similar water loss problem, anyway to cut a long story short, have you checked the water pump.

I was loosing water but could never find any sign of it under the bongo, it would loose water over night. Check filler tank on a morn and it was low, top up, drive to work, come home check level fine. Wake up next day check and it would be empty again.

It turned out to be the water pump, on the cold nights the seal was retracting and dripping enough water out to empty the header tank. I never saw the water in the morning as it was being caught on the sump tray.

For your info, before I worked out it was the water pump, it cost me a new rad, a new cylinder head (cracked in 3 places due to a friend doing a long run in it over a couple of days and not following my advice of filling up the header tank, idiot). The leak was causing an air cavitation in the cylinder head.

I only discovered the water pump was the cause when it was still using water after I changed the cylinder head.

After I changed the water pump, I have never lost a drop of water since.

My advice now is always start at the water pump if there is no other obvious problem.

cheers,hope this helps, apologies if you have already done this, long thread.

That, in my view erifis, is a seriously useful posting, and I will try and remember that. I've got a low coolant alarm fitted. If I do develop a mysterious leak, I now know to add the water pump to the other usual suspects.

Simon - sounds (fingers crossed) like you might be getting on top of it. Fingers crossed you have and the Bongo settles down to the very reliable vehicle it's capable of being. Hats off to you taking on work like that. Even if I had the skill, my back would give out before I'd got half way through

[Simon Jones]

I replaced the water pump fairly early on in the saga. The main reason was that I was concerned that the vanes might have corroded which would result in poor circulatation & over-heating. I was pleasantly surprised to fine the original one was in perfect condition. However, I'm now happy that the cooling system is now in good working order, so it was worth replacing anyway.

Mike - I think my back is knackered now - what a daft place to stick an engine!

[mikeonb4c]

Mike - I think my back is knackered now - what a daft place to stick an engine!

It's an effing great place to stick an engine.....

.....as long as you don't want to work on it.

Actually it's not that bad in many respects I reckon. I think the depressing truth is all car engines are back killers if you have to spend any time bent over diddling with them. Bummer

[Doone]

Good luck Simon, hopefully it's sorted now. Looks like you found out the hard way, just how absolutely vital a clean smooth finish is on the head, before re-fitting. The slightest bit of grit or unevenness is a killer. My other half would agree with you about the 'back-breaking' part.

[helen&tony]

Hi Simon
I sincerely hope you have fixed the problem....It sounds more than hopeful.
This cooling system seems to be throwing a few "wobblies" lately!!!!
Cheers
Helen