Loss of water from expansion tank - advice wanted

Post by **Simon Jones** » Wed Mar 26, 2008 9:20 pm

Yesterday, after a journey of only a couple of miles, I stopped & noticed a pool of water under the front of the van. On inspection, it seems like I've lost a litre or two of coolant from the overflow. There was no sign of overheating (short trip, cold evening & the engine temp gauge stayed on its usual 11 o'clock position). Didn't have any time to investigate further before putting the van away, but there is no sign of any leaks from any hoses. The plan this weekend is to drain the coolant, reverse flush any crud out with the hose pipe, refill with a 50:50 mix of anti-freeze & the bleed as per the usual instructions.

I'm hoping that there was just an airlock which has expanded & forced out the coolant. The other (more expensive) possibility is that the head gasket has failed & its the compression pushing the water out. Hopefully, either way, no serious damaged has occured as it was such a brief journey.

Has anyone had these symptoms & if so, what was the cause / solution? I've got one of Haydn's alarms on order (better late than never!)

nfn · Post by **nfn** » Wed Mar 26, 2008 9:29 pm

If an airlock pushed the coolant out there still must be a leak somewhere: either coolant from a pipe or waterpump, or the dreaded head gasket... I don't know if head gaskets are ever likely to fail without being preceded by an overheating incident.

coco bongo · Post by **coco bongo** » Wed Mar 26, 2008 9:29 pm

This is what happened to mine when the head went, be very careful, personally i wouldn't drive it again.

Get it to a mechanic asap. Mine was also producing white smoke when the engine is warm, and also throwing the water out the breather tube.

If it is a gasket, and you have noticed it in time, you may be one of the lucky ones to escape a new head.

Post by **Simon Jones** » Wed Mar 26, 2008 9:39 pm

Any easy way to check if head gasket has gone? I've used a compression tester on petrol engines to check for problems with valves & piston rings. Is there an equivalent test for a diesel?

Will have to find a local Bongo expert in Salisbury - I usually go to Bellhill Garage, but thats too far to risk a journey to.

coco bongo · Post by **coco bongo** » Wed Mar 26, 2008 9:48 pm

Have you checked the oil to see if coolant is in the oil?, smelt exhaust gases in the expansion tank?.

Not sure of any others but im sure more will follow from others.

mikeonb4c · Post by **mikeonb4c** » Wed Mar 26, 2008 9:50 pm

Sounds weird it should have happened out of the blue Simon. I can't remember but have you had any issues with overheating before?

mister munkey · Post by **mister munkey** » Wed Mar 26, 2008 9:50 pm

I might as well be the first this time to advise fitting a collant loss alarm while you're fettling with the system. Peace of mind, even when all current problems are fixed.

A sound investment.

coco bongo · Post by **coco bongo** » Wed Mar 26, 2008 9:57 pm

mister munkey wrote:I might as well be the first this time to advise fitting a collant loss alarm while you're fettling with the system. Peace of mind, even when all current problems are fixed.

A sound investment.

I agree also with the munkey on this one, I fitted mine too late and wished i had it as soon as i heard about them. Useful things those "collant" alarms

Post by **Simon Jones** » Wed Mar 26, 2008 10:05 pm

Thanks for replies so far. No history of overheating before, no sign of oil in expansion tank (although no water either!) Have not checked for any sign of water in the oil - may just nip up to the garage to check that now.

I've been following another thread which suggests removing the rad for a thorough flushing & if necessary replacing if there are signs of blockage.

coco bongo · Post by **coco bongo** » Wed Mar 26, 2008 10:16 pm

Good stuff Simon, on the radiator side, if you haven't touched it before it might be worth a go. Or maybe a new one if you can afford it. My rad cost £130 ish. All the best with it and keep us posted.

Post by **Simon Jones** » Wed Mar 26, 2008 11:20 pm

Had a closer look: siphoned off some coolant - no sign of oil in the mixture. No sign of the white goo in the oil filler cap or dipstick & no white smoke. Ran the engine for a few minutes - no sign of any pressure in the expansion tank & I couldn't hear anything unusual.

How difficult is it to change the thermostat? The manual suggests you need to remove the front propshaft, but I'm sure I've read that this is not necessary.

maxheadroom · Post by **maxheadroom** » Wed Mar 26, 2008 11:39 pm

How difficult is it to change the thermostat? The manual suggests you need to remove the front propshaft, but I'm sure I've read that this is not necessary.

Quite easy I didn't remove the prop shaft, you just need a long reach on your socket set.
Ref your water leak, do check your water pump it's on the front of the engine. Fingers crossed.

The Great Pretender · Post by **The Great Pretender** » Wed Mar 26, 2008 11:40 pm

Have you bled the system SJ ?

dipstick · Post by **dipstick** » Wed Mar 26, 2008 11:48 pm

It sounds to me as if a coolant loss alarm would not have been any good in this situation where coolant was being forced out of the coolant overflow as the expansion tank would be full all the time.

Post by **Simon Jones** » Thu Mar 27, 2008 12:39 am

TGP - not bled it yet. Will flush it all out first & then try the 'see saw' method which seems to be the one most recommended.

Loss of water from expansion tank - advice wanted

Loss of water from expansion tank - advice wanted

Coolant Loss