Coolant issue.
Discussion
pb450 said:
So in summary Alun, you can find virtually nothing wrong with all your checks...?
EXACTLY, I appreciate this because I'm wondering if I'm going mad! The plugs are terrible. To lean. Need to check bores and pistons ASAP.
But why.
Ive been sitting here annalysing my driving over the last two months. New tyre's, then Dif replaced, I've used it to go to a cafe about 10 miles away 4 times, a few runs testing tyre's in winter so bloody slow. Dog walking trips, a couple of trips to my mother and family, a few local journeys.
I'm mindful of most things, I run the engine up, I drive further than I need to to make sure it's fully warmed up before switching it off, I don't get mayo as I don't stop start it when it's cold, it's started and warmed then turned off. It's like a bloody jewel to me!
I can't see how this has happened. Anyway it has and I'll have to find away to repair it.
It's hard enough to maintain/ restore an old car let alone have to re visit stuff you thought you'd cured!
Know what you mean... Your reliability confidence takes a big dent, until you know exactly why and what - especially after so many trouble-free miles. Sounds like you have bags of 'mechanicle sympathy' with your driving style, so don't beat yourself up there.
Assume your engine builder will take a good exploratory look to identify cause and effect. With luck he'll find the former but not the latter! Until then, I'd say you've done everything you can yourself to check it all out.
Patience is the next step, until 'the Man' can assess further. Hopefully that's really soon!
Have faith.
Assume your engine builder will take a good exploratory look to identify cause and effect. With luck he'll find the former but not the latter! Until then, I'd say you've done everything you can yourself to check it all out.
Patience is the next step, until 'the Man' can assess further. Hopefully that's really soon!
Have faith. From what you have explained I would be surprised if the issue is a slipped liner. I have heard two cars with slipped liners and both have sounded pretty horrific, the kind of noise where you have to click the engine straight off again as you don't want to do any further damage.
Keep us updated Alun and I hope it is a relatively cheap fix. I cannot imagine the issue being too bad as you have a recently rebuilt engine and MBE so you know it is running right.
Keep us updated Alun and I hope it is a relatively cheap fix. I cannot imagine the issue being too bad as you have a recently rebuilt engine and MBE so you know it is running right.
ClassicChimaera said:
A liner once slipped stays slipped!
I'm no expert on slipped liners but i'm sure I have read somewhere that the liner can move when engine temp starts to climb and can also move back once the engine has stopped and starts to cool.Anyone else with more knowledge than me, or is it my age and my imagination.
I'm no expert on slipped liners but I'd be tempted to have a chemical coolant block test done.Its a cheap test and basically looks for combustion gases bubbling up through the coolant. I would imagine that if a liner had slipped/moved then it would allow combustion gases to travel in an unplanned route through the head gasket sealing?
Just a thought as it's not an invasive,expensive or complicated test that may offer some reassurance?
I may be barking up the wrong tree, I'm sure others will confirm or deny the viablility of this initial diagnosis.
Hope it gets sorted without major works for you.
Just a thought as it's not an invasive,expensive or complicated test that may offer some reassurance?
I may be barking up the wrong tree, I'm sure others will confirm or deny the viablility of this initial diagnosis.
Hope it gets sorted without major works for you.
TJC46 said:
I'm no expert on slipped liners but i'm sure I have read somewhere that the liner can move when engine temp starts to climb and can also move back once the engine has stopped and starts to cool.
Anyone else with more knowledge than me, or is it my age and my imagination.
From V8 Developments web site.Anyone else with more knowledge than me, or is it my age and my imagination.
Although there is little definitive information as to why the cylinder liners on some Rover V8 blocks appear to become 'porous' or start leaking, the most popular theory revolves around a flaw in the block casting.
It is thought that some blocks, particularly those used for the 4.0 litre and 4.6 litre engines, have a small casting defect behind the liners. This defect is between the water jacket in the cylinder block and the back of the liner. Over a period of time, water seems to cross the defect and end up on the back of the liner. This then works its way up the side of the liner and eventually causes a leak pathway all the way up to the block face.
This pathway allows the hot gasses from the cylinder to pass into the water jacket, pressurising the system and adding extra heat to the coolant.
Although at this point the problem is a minor one and may only appear from time to time, it does worsen over a period of time and eventually causes the engine to overheat and expel its coolant on a regular basis.
The worst case scenario is that the engine is stopped with substantial pressure in the water system and the water then is pushed back into the cylinder. If the water is still there when the engine is re-started it cannot be compressed and a 'hydraulic lock' occurs which tends to bend connecting rods, warp heads, lift head gaskets and is generally not very pleasant!
As for the plugs could it just be deposits from the wrong viscosity oil leaking past the oil ring and burning on the plug tip at high temperature causing a white deposit.
When I checked with TVR101 I was told not to use the Iridium plugs and to just use the normal plugs.
Hope for you it is a cheap fix.
Tony91 said:
From V8 Developments web site.
Although there is little definitive information as to why the cylinder liners on some Rover V8 blocks appear to become 'porous' or start leaking, the most popular theory revolves around a flaw in the block casting.
It is thought that some blocks, particularly those used for the 4.0 litre and 4.6 litre engines, have a small casting defect behind the liners. This defect is between the water jacket in the cylinder block and the back of the liner. Over a period of time, water seems to cross the defect and end up on the back of the liner. This then works its way up the side of the liner and eventually causes a leak pathway all the way up to the block face.
This pathway allows the hot gasses from the cylinder to pass into the water jacket, pressurising the system and adding extra heat to the coolant.
Although at this point the problem is a minor one and may only appear from time to time, it does worsen over a period of time and eventually causes the engine to overheat and expel its coolant on a regular basis.
The worst case scenario is that the engine is stopped with substantial pressure in the water system and the water then is pushed back into the cylinder. If the water is still there when the engine is re-started it cannot be compressed and a 'hydraulic lock' occurs which tends to bend connecting rods, warp heads, lift head gaskets and is generally not very pleasant!
As for the plugs could it just be deposits from the wrong viscosity oil leaking past the oil ring and burning on the plug tip at high temperature causing a white deposit.
When I checked with TVR101 I was told not to use the Iridium plugs and to just use the normal plugs.
Hope for you it is a cheap fix.
I had experience of a porous block 3 years ago (1999 4.0). As mentioned above, numerous ideas and suggestions were raised before in the end there was no choice and it had to be taken apart. The evidence once stripped down was just a very small water mark between one of the cylinders and the water jacket, that over time caused gases to seep into the cooling system. The impact was only really noticeable after a long journey when the water inside the expansion tank would rise - 200 miles home from Devon resulted in pressurised coolant coming out the top of the cap when it was unscrewed even when the engine was stone cold. Smaller journey of 70-80 miles resulted in a lower rise to the coolant inside the tank. Although there is little definitive information as to why the cylinder liners on some Rover V8 blocks appear to become 'porous' or start leaking, the most popular theory revolves around a flaw in the block casting.
It is thought that some blocks, particularly those used for the 4.0 litre and 4.6 litre engines, have a small casting defect behind the liners. This defect is between the water jacket in the cylinder block and the back of the liner. Over a period of time, water seems to cross the defect and end up on the back of the liner. This then works its way up the side of the liner and eventually causes a leak pathway all the way up to the block face.
This pathway allows the hot gasses from the cylinder to pass into the water jacket, pressurising the system and adding extra heat to the coolant.
Although at this point the problem is a minor one and may only appear from time to time, it does worsen over a period of time and eventually causes the engine to overheat and expel its coolant on a regular basis.
The worst case scenario is that the engine is stopped with substantial pressure in the water system and the water then is pushed back into the cylinder. If the water is still there when the engine is re-started it cannot be compressed and a 'hydraulic lock' occurs which tends to bend connecting rods, warp heads, lift head gaskets and is generally not very pleasant!
As for the plugs could it just be deposits from the wrong viscosity oil leaking past the oil ring and burning on the plug tip at high temperature causing a white deposit.
When I checked with TVR101 I was told not to use the Iridium plugs and to just use the normal plugs.
Hope for you it is a cheap fix.
In the end I sourced a remanufactured block from Turner Engineering, and the rebuild was carried out by David Batty.
Ironically enough I suffered no other unusual symptoms in terms of overheating or strange noises.
It would appear sadly that block imperfections may be more common than once thought, but although there was obviously expense associated with the rebuild (as mentioned before, you always find a few more things that can / should be done at the same time), there really was nothing else out there that appealed to me in quite the same way.
Good luck with it, hope it turns out to be a simple fix.
Bluebottle said:
Hi Alun..
not read all the posts on this but, did you pull all the plugs and do they all look like the No. 2 plug posted up?
No. I've been over to Powers and I removed plugs there. no 2 had what looked like aluminium sharps on it yesterday and was darker and bloody well looked normal today. All other plugs also came out looking fine. I suggested it might be running lean but according to the boys no. Here's another plug No 6 not read all the posts on this but, did you pull all the plugs and do they all look like the No. 2 plug posted up?
Suns shining so it looks lighter than it is.
Powers are busy, I never booked it in so after bleeding the system myself I was confident to drive over and let them look.
Pulled plugs and good results with colour today!
To do leak down/ compression tests I'll need to give them more notice which is fair enough as other customers want their cars too.
I can do these tests rather than bother them with it so I'll do both and get a camera down the bores.
Stuck thermostat is a real possibility but it should have boiled over!!
Slipped liner
Cracked block is another.
There is no air in the system. If this problem occurs again and air is in the system then suspect liner/ cracked/ pourus block but until it's apart you can't be sure.
I bled the system, didn't take much if any coolant to top it up and didn't really feel like I'd got much air out but my temps are spot on again so air was in there as far as I'm concerned.
I mentioned sounds like cracking of metal, shocking!
You'd be surprised what noises these engines can make when there over heating.
I might have a weep on a head gasket for all I know.
Run the engine up at Powers and left until fans kicked in and out 4 times and Dom then came over and listened to it. There's nothing wrong with its mechanical operation and anyone can tell you that if you listen to it purr.
I thought it sounded a bit groggy on cold start up( water in bores) yesterday but I can't be sure. I'll monitor that as that's a clear pointer.
So engine seems ok, water systems working but I'm still worried about detonation etc so the sooner I look at the pistons the better. No 2 especially.
Cheeers for the words guys, it all helps.
Pulled plugs and good results with colour today!
To do leak down/ compression tests I'll need to give them more notice which is fair enough as other customers want their cars too.
I can do these tests rather than bother them with it so I'll do both and get a camera down the bores.
Stuck thermostat is a real possibility but it should have boiled over!!
Slipped liner
Cracked block is another.
There is no air in the system. If this problem occurs again and air is in the system then suspect liner/ cracked/ pourus block but until it's apart you can't be sure.
I bled the system, didn't take much if any coolant to top it up and didn't really feel like I'd got much air out but my temps are spot on again so air was in there as far as I'm concerned.
I mentioned sounds like cracking of metal, shocking!
You'd be surprised what noises these engines can make when there over heating.
I might have a weep on a head gasket for all I know.
Run the engine up at Powers and left until fans kicked in and out 4 times and Dom then came over and listened to it. There's nothing wrong with its mechanical operation and anyone can tell you that if you listen to it purr.
I thought it sounded a bit groggy on cold start up( water in bores) yesterday but I can't be sure. I'll monitor that as that's a clear pointer.
So engine seems ok, water systems working but I'm still worried about detonation etc so the sooner I look at the pistons the better. No 2 especially.
Cheeers for the words guys, it all helps.
Thinking aloud again, detonation, I'd expect to feel somethimg more through the transmission and slight hesitancy, and bent rods.
Other than a tapping sound even on feathered throttle opening there was no stutter at all.
Tapping was every 20 -30 seconds or so.
Hmmm means nothing, I'd recognise pinking from 50 paces away, but detonation, not so sure.
Other than a tapping sound even on feathered throttle opening there was no stutter at all.
Tapping was every 20 -30 seconds or so.
Hmmm means nothing, I'd recognise pinking from 50 paces away, but detonation, not so sure.
Hi Al, sorry to hear of your woes. Been reading through the thread and you seem to have been given lots of good advice on what to check and do. That pic of number 6 plug looks in good shape. Must admit my first thought earlier on was a faulty thermostat. They can and do stick or play up - not just fail open or closed. Might be worth fitting a nice clean plug to number 2 and running it again then look to see if you get any deposits again.
Good luck with it mate.
Good luck with it mate.
Alun pinking is just another term for detonation, as is knock.
It's been my experience the Rover V8 is an engine that will tolerate all sorts of heat, poor quality fuel, and excessive ignition advance before it even comes close to pinking (as we used to call it).
Heavily modified versions aside and a standard TVR 4.0 or 4.6 can hardly be considered heavily modified, in these guises the Rover V8 is a very low compression engine and is very resistant to knock.
Even under load I found you can push the timing to 40 degrees or more and it still won't show detonation, it won't make it's best power like that but it certainly won't rattle either.
The way you describe your noises they sound an awful lot like steam pockets to me, this is normally the direct result of either a circulation issue (why I suggested the water pump) or combustion gasses getting into the water jacket.
Personally I'd still go with circulation.
It's been my experience the Rover V8 is an engine that will tolerate all sorts of heat, poor quality fuel, and excessive ignition advance before it even comes close to pinking (as we used to call it).
Heavily modified versions aside and a standard TVR 4.0 or 4.6 can hardly be considered heavily modified, in these guises the Rover V8 is a very low compression engine and is very resistant to knock.
Even under load I found you can push the timing to 40 degrees or more and it still won't show detonation, it won't make it's best power like that but it certainly won't rattle either.
The way you describe your noises they sound an awful lot like steam pockets to me, this is normally the direct result of either a circulation issue (why I suggested the water pump) or combustion gasses getting into the water jacket.
Personally I'd still go with circulation.
It's very difficult to diagnose something over the Internet but if you can get a video up of the issue when it arrises that would help. The fact Dom has said it sound fine should put your mind at rest, it could be a combination of little things and now your second guessing yourself, the ticking could just be down to a lazy lifter I had it on my p38 nothing to worry about
Reassuring words. Cheers boys
Hard to detect on the internet, even harder to describe it
Cracked blocks, bent rods, serious talk. No wonder I have silver hair
Tell me do I worry to much, if you'd heard and felt those noises I felt last night. Bloody aider man!
Iain, I'm going to swap no 2 around for now and see what it does in another bore and visa versa. All plugs today looked good and No 2 looked very different from last night! I took it out and stood there embarrassed.
You have no idea what Dom has to put up with.
Watched some lovely machining going on, I'd quite like another engine rebuild in another 20,000 miles when I can afford it.
Trouble is with Tivs, you need a pot of 5K waiting,,,, just in case
When you ain't got that pot it is a nervy experience.
So here I am, still not sure yet feeling like the car sounds and runs very good. They must be strong things.
Bugger it, I'll change the stat cos I can't handle that s
t again,,, see how it goes.
Dave, water pump. I did notice today from 900 revs and rising to about 1400 with ear very close a slight high pitched whine. You can't notice it if you stand up but it's there.
Air in the system it just has to be, so it's all down to if and when I have air again really because once it's bled and sealed it should not get air back in.
It's not a nice prospect so we'll just have to see.
For a mechanic bleeding these cars us as basic as it gets, if you do it properly you can't really go wrong. I've done it enough times to think it's like checking the oil. I swear I could hear water rushing in the heater matrix on the way home.
Rather than wait for this to happen again I'm going to bleed it pretty soon and see what I get.
If I had air in the system and my funnel with coolant drops by about 5 mm, is that enough water missing to cause air locks. Trying to be accurate it did take say half a cup full. Bugger all really but trapped air doesn't nesessarily take up much space,,,, or does it.
Let's just hope I had air, it's gone and my life returns to some normality.
The thought of no Tvr drug today was quite nerve wracking. Need to get a life.
When your going through these woes, mechanics words are like gold dust. Thanks for the thoughts on this gentlemen.
We'll see.
,,,
Hard to detect on the internet, even harder to describe it
Cracked blocks, bent rods, serious talk. No wonder I have silver hair
Tell me do I worry to much, if you'd heard and felt those noises I felt last night. Bloody aider man!
Iain, I'm going to swap no 2 around for now and see what it does in another bore and visa versa. All plugs today looked good and No 2 looked very different from last night! I took it out and stood there embarrassed.
You have no idea what Dom has to put up with.
Watched some lovely machining going on, I'd quite like another engine rebuild in another 20,000 miles when I can afford it.
Trouble is with Tivs, you need a pot of 5K waiting,,,, just in case
When you ain't got that pot it is a nervy experience.
So here I am, still not sure yet feeling like the car sounds and runs very good. They must be strong things.
Bugger it, I'll change the stat cos I can't handle that s
t again,,, see how it goes. Dave, water pump. I did notice today from 900 revs and rising to about 1400 with ear very close a slight high pitched whine. You can't notice it if you stand up but it's there.
Air in the system it just has to be, so it's all down to if and when I have air again really because once it's bled and sealed it should not get air back in.
It's not a nice prospect so we'll just have to see.
For a mechanic bleeding these cars us as basic as it gets, if you do it properly you can't really go wrong. I've done it enough times to think it's like checking the oil. I swear I could hear water rushing in the heater matrix on the way home.
Rather than wait for this to happen again I'm going to bleed it pretty soon and see what I get.
If I had air in the system and my funnel with coolant drops by about 5 mm, is that enough water missing to cause air locks. Trying to be accurate it did take say half a cup full. Bugger all really but trapped air doesn't nesessarily take up much space,,,, or does it.
Let's just hope I had air, it's gone and my life returns to some normality.
The thought of no Tvr drug today was quite nerve wracking. Need to get a life.
When your going through these woes, mechanics words are like gold dust. Thanks for the thoughts on this gentlemen.
We'll see.
,,,
pb450 said:
Know what you mean... Your reliability confidence takes a big dent, until you know exactly why and what - especially after so many trouble-free miles. Sounds like you have bags of 'mechanicle sympathy' with your driving style, so don't beat yourself up there.
Assume your engine builder will take a good exploratory look to identify cause and effect. With luck he'll find the former but not the latter! Until then, I'd say you've done everything you can yourself to check it all out.
Patience is the next step, until 'the Man' can assess further. Hopefully that's really soon! Have faith.
Mechanical sympathy is my pride. Assume your engine builder will take a good exploratory look to identify cause and effect. With luck he'll find the former but not the latter! Until then, I'd say you've done everything you can yourself to check it all out.
Patience is the next step, until 'the Man' can assess further. Hopefully that's really soon!
Have faith. Even racing drivers have to smooth out all the edges to be fast.
I consider smooth slow speed driving as much a skill as high speed driving and with a new diff I'm hardly throwing horsepower through it!
I've missed a number of responses on here, (blaze away ) Frank. Thankyou so much, very kind.
Im still in shock I think. Not sure what to make of it all.
I'm going sprinting with my mate tomorrow in a £800 MGTF makes you wonder some days.
Steve_D said:
If you think it is lean have you checked to see if your fuel pump is producing the right pressure?
Somewhere else on the TVR forums in the last few days the same problem was identified with a pump free flowing nicely into a bucket but not able to maintain a pressure.
Steve
Interestingly enough, my RV8 is fitted with Speed Six injectors and fuel regulator. Somewhere else on the TVR forums in the last few days the same problem was identified with a pump free flowing nicely into a bucket but not able to maintain a pressure.
Steve
I've just replaced the fuel filter. But not the pump. It's always worked as you'd expect and no abnormal noises from it. I'll keep thst one in the back of my mind over fuelling. Jason wasn't at Powers yesterday, everyone's got jobs to do and thebplugs as far as Dom was concerned were ok. Contrary to earlier when I'd pulled the plugs they had a nice brown look.
I've had a problem with idle screw once, running rough, Jason reckoned the idle screw had been turned over 360 from where it should have been. Im adamant I haven't touched it or moved it so far out of position. I've been watching it since, it hasn't moved as far as I can tell as I've been wondering if it doesn't bind well and turns on it's own accord ( vibration) but it's a red herring!
run it and if the symptom returns, pull all the plugs...
If they all look similar then its a fueling issue which could be a weak/dying fuel pump of weak regulator, dirty fuel or debri/blockage in fuel tank or even water, it could be the carbon canister causing suction in the tank...can you here the tank making a noise? i have had all of the above at some point. but none caused air in the cooling system.
when you pull the plugs does one bank look different to the other? if so then injector bank firing issue or faulty lambda but both would usually make one bank run very rich unless the lambda is sticking closed and not open?
If its localised to one plug then its down to a leak in that cylinder or that one injector, as poor ignition would cause it to run cool not hot.
I had a head gasket breakdown between #5 & #7 bores, not enough to cause hydrocarbons in the coolant, initially when trying to diagnose it but if i took the revs over 4.5k it would start to pressurize the water jacket causing symptoms similar to an air lock in system. the leak caused #5 to scavenge from #7 making it run very lean on that one cylinder and the plug looked like yours when we pulled it, but not until i'd melted a piston at Snetterton
The other symptom was the occasional sound like a mechanical ticking similar to a leaking manifold gasket. A leak down test (not a basic compression test) would rule this possibility out as you will here the air leaking and can track down the location with stethoscope.
Could be something completely different but the above are all issues i have had in the past.
If they all look similar then its a fueling issue which could be a weak/dying fuel pump of weak regulator, dirty fuel or debri/blockage in fuel tank or even water, it could be the carbon canister causing suction in the tank...can you here the tank making a noise? i have had all of the above at some point. but none caused air in the cooling system.
when you pull the plugs does one bank look different to the other? if so then injector bank firing issue or faulty lambda but both would usually make one bank run very rich unless the lambda is sticking closed and not open?
If its localised to one plug then its down to a leak in that cylinder or that one injector, as poor ignition would cause it to run cool not hot.
I had a head gasket breakdown between #5 & #7 bores, not enough to cause hydrocarbons in the coolant, initially when trying to diagnose it but if i took the revs over 4.5k it would start to pressurize the water jacket causing symptoms similar to an air lock in system. the leak caused #5 to scavenge from #7 making it run very lean on that one cylinder and the plug looked like yours when we pulled it, but not until i'd melted a piston at Snetterton
The other symptom was the occasional sound like a mechanical ticking similar to a leaking manifold gasket. A leak down test (not a basic compression test) would rule this possibility out as you will here the air leaking and can track down the location with stethoscope.
Could be something completely different but the above are all issues i have had in the past.
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