Overflow when cold
Discussion
Here's a mystery. I can get in the Griff, go on a trip, put it back in the garage nice and warm, no problem, no leaks. But if I just back it out of the garage for some polishing etc, then drive it back in - ie engine is cold - it then proceeds to piss a small cupful of coolant onto the floor via the spolier. I've looked all round with a torch and still can't figure where it's coming from. Any ideas folks?
'Is youtr drive on a slope,The water might be sitting somewhere then coming out when u move it out.'
Very slightly, but it also does it in the garage which is flat.
'It may well be "pissing" out just the same when you take it out for a run, its just that you don't see it, and when you return the heat of the engine/rad evaporates it.'
If it was coming out at that rate when I was going along it would be empty in 10 miles! The dribbling starts a little while after I turn the engine off and continues for perhaps a minute. But only if I've just moved the car a short distance from cold, not after a journey.
'Is it over-filled perhaps?
If I fill the expansion tank more than halfway then it comes out again pretty promptly (though again I don't know where!). Currently the level is just below half way and seems pretty constant in normal driving. The engine doesn't overheat either.
So the mystery continues!
Very slightly, but it also does it in the garage which is flat.
'It may well be "pissing" out just the same when you take it out for a run, its just that you don't see it, and when you return the heat of the engine/rad evaporates it.'
If it was coming out at that rate when I was going along it would be empty in 10 miles! The dribbling starts a little while after I turn the engine off and continues for perhaps a minute. But only if I've just moved the car a short distance from cold, not after a journey.
'Is it over-filled perhaps?
If I fill the expansion tank more than halfway then it comes out again pretty promptly (though again I don't know where!). Currently the level is just below half way and seems pretty constant in normal driving. The engine doesn't overheat either.
So the mystery continues!
I had an ill fitting bleed plug, you could just make out a hairlike stream of water making its way accross the engine bay and evaporating off the exhaust.
A new nut and some PTFE tape sorted it out.
Mooch though these pages for other ideas:
http://ourworld.compuserve.com/homepages/Peter_Beech/TVR/wsncont.htm
A new nut and some PTFE tape sorted it out.
Mooch though these pages for other ideas:
http://ourworld.compuserve.com/homepages/Peter_Beech/TVR/wsncont.htm
I had the reverse of this in that a short run including fans on, no problem, but a good long blast developed leaking as you describe.
Mine was a core leak that was only opening up if the engine had been very hot and was cooling down slowly in the garage, a re-cored rad sorted it.
I’d guess you have a similar problem and the leak is only opening up under certain expansion conditions.
Cheers,
Simon.
Mine was a core leak that was only opening up if the engine had been very hot and was cooling down slowly in the garage, a re-cored rad sorted it.
I’d guess you have a similar problem and the leak is only opening up under certain expansion conditions.
Cheers,
Simon.
'but a good long blast developed leaking as you describe.'
I can understand that (my rad was recored last month incidentally, but the car has always done it I think.
'the leak is only opening up under certain expansion conditions.'
But it's only running just long enough to drive it into the garage, eg 20 seconds! Even the manifolds are barely warm to the touch.
I can understand that (my rad was recored last month incidentally, but the car has always done it I think.
'the leak is only opening up under certain expansion conditions.'
But it's only running just long enough to drive it into the garage, eg 20 seconds! Even the manifolds are barely warm to the touch.
quote:
But it's only running just long enough to drive it into the garage, eg 20 seconds! Even the manifolds are barely warm to the touch.
I would buy a lottery ticket as you must be the lucky guy whose interspatial gaps in the coolent molecules aligns up with the corresponding gaps in the ally container or pipework so that a small amount slips through. Once slipped through the gaps no longer align and you get a puddle. The reasons it gets on the fllor is that a further alignment takes place and the coolent slips through the GRP onto the floor. There are occassions where it will also slip through the floor giving the impression that the car is not leaking...
Does that help?
Steve
Did you fit the rad yourself and are you sure it was re-cored and not just repaired. I hand two repairs done both of which passed pressure tests yet failed within a couple of days of being refitted, it was then re-cored and problem solved.
It sound like yours is opening up when cold but only leaks as the pressure starts to build, the heat and associated expansion then closes it up again, either that or Steve’s molecule theory.
Has the bottom hose connection has been made correctly and or is the hose damaged, Its easy to nick the hose with the jubilee clips if over tightened and that bottom connection is a b***h.
Simon.
It sound like yours is opening up when cold but only leaks as the pressure starts to build, the heat and associated expansion then closes it up again, either that or Steve’s molecule theory.
Has the bottom hose connection has been made correctly and or is the hose damaged, Its easy to nick the hose with the jubilee clips if over tightened and that bottom connection is a b***h.
Simon.
quote:
Err ... if the engine has only just been run for a few mins, isn't it likely that the bypass valve wotsit hasn't even opend yet, so there won't be anywater circulating in the rad? ... or have I been drinking coolant again (along with Steve by the sound of it).
You are referring to the thermostat and there is a bypass for this anyway so there is some flow into the rad irrespctive of my, your or the thermostat's state.
Still think the molecular theory is worth looking at except that when you look at it, it disturbs the probability cloud as an electron observed is an electronm disturbed. This is also why when you look at it, you can't find anything wrong...
Steve
'you must be the lucky guy whose interspatial gaps in the coolent molecules aligns up with the corresponding gaps in the ally container or pipework so that a small amount slips through...'
I recall my chemistry teacher telling us that since a liquid contains molecules moving randomly in all directions, there was a chance that they would momentarily all move the same way at once - so that in theory your pint of beer could suddenly hurl itself upwards out of the glass. The only way to try to prove this theory is to keep drinking pints of beer until it happens - an ideal research project for the PH team perhaps?!
Simon B, yes it was a recore, done by Offord. I shall have to leave it outside with the engine running for a couple of minutes and if you theory is correct, it should widdle for a moment then stop as it heats up further. We shall see...
I recall my chemistry teacher telling us that since a liquid contains molecules moving randomly in all directions, there was a chance that they would momentarily all move the same way at once - so that in theory your pint of beer could suddenly hurl itself upwards out of the glass. The only way to try to prove this theory is to keep drinking pints of beer until it happens - an ideal research project for the PH team perhaps?!
Simon B, yes it was a recore, done by Offord. I shall have to leave it outside with the engine running for a couple of minutes and if you theory is correct, it should widdle for a moment then stop as it heats up further. We shall see...
quote:
I thought the Serp engine did not have a bypass,into the rad, for the water stat.
Done externally through the heater pipework and is also one of the reasons why many put some small holes throught the stat to encourage some flow. Seen this on a lot of late Wedges as well. The stat does not set the operating temp of the engine but really allows the engine to warm up quicker.
There is a school of thought that this bypass should be improved and John Eales sells a bypass stat housing.
Steve
quote:
I thought the Serp engine did not have a bypass,into the rad, for the water stat.
Done externally through the heater pipework and is also one of the reasons why many put some small holes throught the stat to encourage some flow. Seen this on a lot of late Wedges as well. The stat does not set the operating temp of the engine but really allows the engine to warm up quicker.
There is a school of thought that this bypass should be improved and John Eales sells a bypass stat housing.
Steve
quote:
There is a school of thought that this bypass should be improved and John Eales sells a bypass stat housing.
IMO the first thing that happens when this system gets a leak (especialy from the rad)is the engine & waterpump dry out..no coolant flow..the stats upstream of the waterpump and opens when the steam gets there!
most stat housings on these have a flatted face for tapping etc and I was looking to do a mod so as it will be the best place possible to top up from as your filling the engine direct rather than via the expansion tank and through the rad route, is this what the John Eales housing does?
or how about an electic driven waterpump that's temperature/flow controlled
heliox
Maybe i have had and have quite special cars, as my engine temp is dictated by the water stat. It stays closed until the engine is up to temp when it opens. Air passing through the rad controls the temp from then on. If the rad gets too cold then the stat closes(in the winter). So there is no bypass to the rad on a serp engine, just through the heater matrix, of course only if the heater valve is open. Actually thinking about it, i do have a car that the temp is not dictated by the water stat, its air cooled!
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