Weird coolant leak !!

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Jacobus

Weird coolant leak !!

Post by Jacobus » Mon Aug 29, 2011 2:15 pm

Three days ago having parked up done shopping got back to vehicle a wet patch under join of engine with gearbox but when I looked no sign of any damp, thought perhaps it had been another vehicle and I had not noticed.

Today drove 6kms into Lagos parked up,noticed smell of coolant, looked under vehicle and there was coolant dropping onto the ground at a fast rate of knots. Up with drivers seat and bonnet but no sign of leak, left vehicle to cool down whilst we went shopping and also bought 4x5 litres of water expecting the worst. Back at vehicle reservoir was empty, put in about 2 litres then started engine no sign of leak? Decided to take a chance drove 6kms home had lost about 1 litre but no leaks onto ground and temp. gauge did not rise above it's normal position. The whole thing reminded me of a pressure release valve but you dont get that on a vehicle's coolant system normally.

Both seats up, done a search as far as possible ran the engine, but cannot see where leak may be other than it appears to be towards the rear of the engine. Anyway what kind of leak heals itself ??

No Bongo garages out here where we live in Portugal any assistance would be more than welcome. cheers...Jacobus
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Re: Weird coolant leak !!

Post by francophile1947 » Mon Aug 29, 2011 2:19 pm

Check the water pump seal - coolant runs back along the sump guard.
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Re: Weird coolant leak !!

Post by widdowson2008 » Mon Aug 29, 2011 2:53 pm

Rear of engine?
Have a look underneath around the rear heater pipes.
Another possibility is a leaking core plug at the rear of the engine block. One of these two:
Image

As john says, a leak can run along the undertray so it could be from anywhere.
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Re: Weird coolant leak !!

Post by helen&tony » Mon Aug 29, 2011 3:25 pm

Hi
I had an annoying leak, after replacing all the hoses...water pump, as John says...They are a pig to spot...I looked under the pump with a torch...put leak detector in, used UV light....NOTHING...Then I tried a VERY bright high-power torch, when engine was cold in the morning...not thinking it would see any better than other lights, but there it was...a small globule of water near the bottom pulley....tested that twice...yep...leak found.....
First spot of water/ sign of leak was the same area as yours...also, feel in around where the sump plug access hole is
BUT...as Steve says...could be anywhere :(
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Re: Weird coolant leak !!

Post by Jacobus » Mon Aug 29, 2011 3:27 pm

Thanks guys, I'll check both replies, but the coolant was coming straight down not off the sumpguard so maybe the core plug could be the answer? Once more dear friends, into the breach :wink: cheers, Jacobus.
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Re: Weird coolant leak !!

Post by haydn callow » Mon Aug 29, 2011 3:32 pm

Check the pipe that runs over the starter motor..........I'll be in Lagos again in 5 weeks....Playing golf at Boa Vista
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Re: Weird coolant leak !!

Post by haydn callow » Mon Aug 29, 2011 3:33 pm

Seeing as the tank went empty.....find the leak....sort it......BLEED IT....if not you will be trying to get a cylinder head sorted in the near future...
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Re: Weird coolant leak !!

Post by bigdaddycain » Mon Aug 29, 2011 4:54 pm

Easier said than done if that's your sole means of transport... For starters i'd be inclined to remove the sump guard tray for a few days whilst leak hunting... You may be in luck and find that the leaking hose (if indeed that's what it is) May be near the end of the hose and a temporary repair can be employed by simply shortening the hose for a TEMPORARY fix till a new hose can be sourced. If you have the inclination, take a new strip of white bandage, and loop a section towards each end of any accesible hose that is visible...Then check the bandage strips after you know you've lost some coolant... If one bandage is stained, that may give a clue as to where the leak is situated and may help in tracing this infernal leak. :wink:
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Re: Weird coolant leak !!

Post by haydn callow » Mon Aug 29, 2011 5:14 pm

Maybe.....but if the tank was empty (2 liters added) then there will almost certainly be air within the system.
No brainer to me......
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Re: Weird coolant leak !!

Post by bigdaddycain » Mon Aug 29, 2011 5:23 pm

There probably WAS... but it's been driven since then.... :? Unless it's actually taking on air via the leak (possible, but unlikely) Then the chances are a small amount of air would have been taken on, but not enough to warrant a bleed...certainly not enough air that the bongo wouldn't have bled back out itself. By all means bleed it if it makes you feel better! Was there any signs of overheating at all?
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Re: Weird coolant leak !!

Post by missfixit70 » Mon Aug 29, 2011 6:46 pm

Has the temp gauge been modified at all or have you got any other indication of temp? the standard gauge will not tell you anything useful re overheating, until it already is.
2 litres is a lot of coolant to have lost & as has already been said, chances are you'll get an airlock, hell of a chance to take by not bleeding it, there have been too many instances where people haven't bled it & ended up cooking the head. Not trying to scaremonger, just trying to stop you causing more damage by being complacent about the cooling system. Hopefully you got away with it, at least 6 km isn't very far so you may not have got hot enough to cause an issue. As has been said in other threads, if the front heater is working it's a bit of an indication that the system is working, but it's a last resort method to use IMO.
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Re: Weird coolant leak !!

Post by haydn callow » Mon Aug 29, 2011 7:46 pm

It's been driven 6k's since then....about 4 miles.....hardly a fair test.
I stick to my advice....Don't drive it untill you have found the leak...fixed it and Bleed it....
It may well be o.k. but the other side of the coin could be a month off the road and a bill for 2000 euros.
Taxis are very reasonable in Lagos.
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Jacobus

Re: Weird coolant leak !!

Post by Jacobus » Mon Aug 29, 2011 9:02 pm

Hi Folks, thanks for all the help and info, 4 hours later leak found, it has to do with the heating side of things. If I can remember how I'll put a photo up. The pipe has a double bend and is just behind the air filter and goes into the block and drops down to a junction with the heater pipes near the rear heater. The leak was at the block entry.

The engine had cooled by the time we got back to it with 20 litres of bought water but I only needed two. Temp gauge stayed at normal for the 6kms home a risk, but I do have the coolant alarm by Ace Answers but pointer never reached it and outside temp was about 26C. To be fair it's a bit difficult to do a bleed in a public car park for a start if I'd got caught it would be a heavy fine so one eye on temp gauge and other for road. On getting home and parking up, no sign of a leak then or even an hour later that's what I found weird, usually a leak is a leak.

Thanks to everybody for advice and help, very much appreciated. .. Cheers, Jacobus.
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Re: Weird coolant leak !!

Post by missfixit70 » Mon Aug 29, 2011 9:15 pm

That's one of the usual top suspects, it can often be trimmed & pushed back onto the spigot, as a temporary fix, the hose over the starter motor going down to the heater inlets.
At least you've got the Mason alaram which makes the temp gauge more sensitive & tell you something useful, but I'd definitely go for a proper bleed to make sure rather than leaving it to chance once it's fixed.
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Re: Weird coolant leak !!

Post by missfixit70 » Mon Aug 29, 2011 9:21 pm

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