Chimaera 450 using some coolant
Discussion
Hi, I noticed my Chimaera 450 is using some coolant - equivilent to about half of the volume of the expansion tank every 100 miles or so.
The (cold) exansion tank is half full at the start of the run, and then empty a few hours after the run (also cold)
I also noticed that when opening the expansion tank cap after a run (when cold) there are usually a lot of gurgling / running water sounds, as if the coolent in the expansion tank is being dumped back into the rad, once the expansion tank cap seal is broken.
I suspect there is a small leak somewhere, or a clip not done up tight enough, although I cannot find any hoses or connections leaking yet.
The car runs at 70C on a run and up to 90C (when the fans kick in) around town and has a brand new aluminuim rad fitted.
Has anyone experienced the same or any other thoughts on the cause?
Many thanks!
The (cold) exansion tank is half full at the start of the run, and then empty a few hours after the run (also cold)
I also noticed that when opening the expansion tank cap after a run (when cold) there are usually a lot of gurgling / running water sounds, as if the coolent in the expansion tank is being dumped back into the rad, once the expansion tank cap seal is broken.
I suspect there is a small leak somewhere, or a clip not done up tight enough, although I cannot find any hoses or connections leaking yet.
The car runs at 70C on a run and up to 90C (when the fans kick in) around town and has a brand new aluminuim rad fitted.
Has anyone experienced the same or any other thoughts on the cause?
Many thanks!
I've posted this before, but here goes again!
I had both the expansion tank and the swirl pot on mine develop pin hole leaks. The leaks weren't enough to produce puddles of coolant: the water being lost was evaporating due to heat in the engine bay I presume.
The one in the expansion tank was a bugger to find as the (multiple) holes were in the bottom near to the welded in spigot.
The swirl tank was a bit easier. There were coolant stains on the side of the tank and the support (but no liquid coolant). The holes were on the welded seam half way up underneath the big jubilee clip used to route the expansion tank hose.
I had both the expansion tank and the swirl pot on mine develop pin hole leaks. The leaks weren't enough to produce puddles of coolant: the water being lost was evaporating due to heat in the engine bay I presume.
The one in the expansion tank was a bugger to find as the (multiple) holes were in the bottom near to the welded in spigot.
The swirl tank was a bit easier. There were coolant stains on the side of the tank and the support (but no liquid coolant). The holes were on the welded seam half way up underneath the big jubilee clip used to route the expansion tank hose.
When it cools down put your nose close to the cap if you release the cap and it burps if it smells of petrol/fumey suspect combustion gases are entering the water jacket HG / block issues , it's simple and basic but seldom lies unless someone as filled cooling system with a contaminated container/jug etc
Zener said:
When it cools down put your nose close to the cap if you release the cap and it burps if it smells of petrol/fumey suspect combustion gases are entering the water jacket HG / block issues , it's simple and basic but seldom lies unless someone as filled cooling system with a contaminated container/jug etc
These cheap kits can help eliminate/determine if combustion gasses are leaking in the water systemhttps://www.ebay.co.uk/itm/323563159915?chn=ps&...
Is the coolant pressurised when you open the coolant cap once it has cooled down (eg 8 hours plus after driving?)
If so - something is pressurising the coolant - and that something will be the engine, ie HGF or similar.
If not - then you've got a leak somewhere, so look for sign of weeping/dried coolant as others have said.
Good luck :-)
If so - something is pressurising the coolant - and that something will be the engine, ie HGF or similar.
If not - then you've got a leak somewhere, so look for sign of weeping/dried coolant as others have said.
Good luck :-)
Chimp871 said:
Zener said:
When it cools down put your nose close to the cap if you release the cap and it burps if it smells of petrol/fumey suspect combustion gases are entering the water jacket HG / block issues , it's simple and basic but seldom lies unless someone as filled cooling system with a contaminated container/jug etc
These cheap kits can help eliminate/determine if combustion gasses are leaking in the water systemhttps://www.ebay.co.uk/itm/323563159915?chn=ps&...
but I was giving the OP'er something he could work with straight away and possible direction , if its like he describes the smell will be unmistakable Are head gasket failures common on rv8 cars, not something I'd heard of?
OP mentions a new radiator, gas it been properly bled?
I recall my 450 had an issue with the pressure cap venting too easily, it would lose coolant then as it cooled one if the hoses would collapse, new cap cured that.
A garage pressure tested my s3 to prove it was the water pump, you might find your leak that way.
Hope this helps.
OP mentions a new radiator, gas it been properly bled?
I recall my 450 had an issue with the pressure cap venting too easily, it would lose coolant then as it cooled one if the hoses would collapse, new cap cured that.
A garage pressure tested my s3 to prove it was the water pump, you might find your leak that way.
Hope this helps.
Thanks so much for all the kind and helpful replies.
I ran the engine today with the expansion tank cap off to observe what happens, and there was a stream of bubbles rising to the surface once the car started to warm up.
So I'm guessing this pressurisation would be caused by a head gasket failure.
I have the car booked in with a specialist on Monday to properly diagnose it, and get it fixed.
I ran the engine today with the expansion tank cap off to observe what happens, and there was a stream of bubbles rising to the surface once the car started to warm up.
So I'm guessing this pressurisation would be caused by a head gasket failure.
I have the car booked in with a specialist on Monday to properly diagnose it, and get it fixed.
phn said:
Thanks so much for all the kind and helpful replies.
I ran the engine today with the expansion tank cap off to observe what happens, and there was a stream of bubbles rising to the surface once the car started to warm up.
So I'm guessing this pressurisation would be caused by a head gasket failure.
I have the car booked in with a specialist on Monday to properly diagnose it, and get it fixed.
Bummer. Out of interest, does the engine oil look contaminated? I ran the engine today with the expansion tank cap off to observe what happens, and there was a stream of bubbles rising to the surface once the car started to warm up.
So I'm guessing this pressurisation would be caused by a head gasket failure.
I have the car booked in with a specialist on Monday to properly diagnose it, and get it fixed.
Riff Raff said:
Bummer. Out of interest, does the engine oil look contaminated?
Strangely not actually - I had a look for "Mayo" in the oil but didn't find anything, the oil at the filler cap and on the dipstick looks perfect.I'll let you all know what the TVR specialist does to fix the issue, in case someone is searching the forums for this problem in the future.
Coolant in the engine oil not always conclusive proof of a BHG or liner issues on the RV8 
or any engine for that matter I have known of two RV8's with cracks behind the liner and the only give away was pressurising the cooling system not surprising when you consider combustion pressure is far greater than the pressure in a normal functioning cooling system , not helped by the fact the HG fire ring sits on the block face (alloy) not on the liner as it should , hence the cooling system can build up pressure but no physical/conventional blown head gasket woes , top hat liners should of come stock from LR 
or any engine for that matter I have known of two RV8's with cracks behind the liner and the only give away was pressurising the cooling system not surprising when you consider combustion pressure is far greater than the pressure in a normal functioning cooling system , not helped by the fact the HG fire ring sits on the block face (alloy) not on the liner as it should , hence the cooling system can build up pressure but no physical/conventional blown head gasket woes , top hat liners should of come stock from LR Zener said:
Hopefully the OP'er as just a standard failed head gasket on either 1, 2, 7, 8, cylinder because they are adjacent to the water openings , old age HG etc or someone been in there before cheapo HG's incorrect bolt torque etc etc
Thanks yes, keeping my fingers crossed it's a "straightforward" HG fault - will let you know how I get on by the end of next week. or someone been in there before cheapo HG's incorrect bolt torque etc etc You could get something like this so you at least know before you go to the expert. Knowlege is power and all that. https://smile.amazon.co.uk/Cylinder-Professional-D...
Hi Philip,
I had this a few months ago with my Griffith 500, ended up making and using this homemede pressure tester. All parts available from your local Toolstation/Screwfix/B&Q for £25 or so...
Pressurise to 15 p.s.i using a foot pump while engine is cold then look for the leak, much safer than when the engine is hot and or running, leave pressurised with newspaper under the car, keep checking for drips then trace back.
Regards,
Brian and a Green Griffith 500
I had this a few months ago with my Griffith 500, ended up making and using this homemede pressure tester. All parts available from your local Toolstation/Screwfix/B&Q for £25 or so...
Pressurise to 15 p.s.i using a foot pump while engine is cold then look for the leak, much safer than when the engine is hot and or running, leave pressurised with newspaper under the car, keep checking for drips then trace back.
Regards,
Brian and a Green Griffith 500
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