low level in coolant header tank

[JRTUPIN]

Hello,

I read consentiousely the forum topic about coolant level and the difficulty to adjust coolant liquid for V8 engine; but I have something curious on my car.

Indeed; after filling my header tank ; and after 3 or 4 hours driving on my car ; the coolant level always stabilizes very low in the header tank ( 1 inch lower than moulded jointline ).

The dashboard red light doesn't glow..

I don't anderstand what's happened because the "lotus procedure" talks about 1 inch above the jointline.

is there something wrong , or is it Ok like that?

do you have an idear ?

Thanks for help

Jean ren

[Iconic Ride]

Bonjour Jean rene!

This could be caused by any number of things, but a quick suggestion comes to mind. The Lotus USA "technical engineer" was in Austin just last week, and I had the good fortune to spend a great deal of time with him, asking all sorts of questions about the car. At one point he requested me to open up the engine hatch so he could have a general look. One of the things he fiddled with was the neoprene hose connecting the header tank to the expansion tank in the right rear wheel arch. It's a "slip fit" affair, held snug by a "preloaded" clamp (I'm referring to the connection at the header tank itself). He easily removed (and reattached) this hose, as the amount of friction holding it on seems to decrease with age. He noted that this can allow air to enter (from atmosphere) the header tank as the coolant level drops when the engine is off (from normal fluid contraction as the coolant cools down to ambient temperature). The level in the header tank will always drop somewhat even with no air leaks, but with one the drop will be greater. He suggested that it was a good idea to replace the existing clamp with an "adjustable" one that would ensure that the connection could be made airtight. I suppose it's also possible that such an airleak could be happening at the expansion tank as well, but this was not discussed.

Good luck!

John

[JRTUPIN]

thank you for help.

after shecking all clamps in my coolant system ( header tank and expansion tank), I only have adjustable clamps for hoses.

But I noticed something curious. After fullfiled at the top my header tank ; and when the engine is warm ( 100

[kyliesmith.com]

So how much water is it losing? how often are you filling up. I dont have the answer to your question but while you are in there check the low coolant level sensor is working properly, it is a very common fault.

In the header tank there is a level sensor which periodically gets stuck full of muck. That stops it floating up to the top or down to the bottom and working as it should. If you look at the header tank there is a large plastic nut on the top, with two pony tail wires connected to it. Carefully pull the connectors off and take out the plastic tube. In the tube is a float, that's what getting stuck. Give the tube a good wash in soapy water let it soak for 1/2 hour and shake it about so you can hear it more freely. Once it's freed up, hook up and least you know this part is working. Ive just done mine a few months ago as preventative maintenance, I think the toggle in the tube in mine was stuck near the top ! and not the bottom which causes the light to come on as others have said, but I only had absolute minimal water loss through a leaking aluminium water pipe which im sorting now.

Edited June 21, 2008 by kyliesmith.com

[Günter]

JR' fill the header tank with fluid in the normal way ,but fill also the expansion tank in the wheel arch (up to the top level) before you get on test runs. I do it with an electric garage water-pump or an manual pump. It works every time (and does regulate itself to the ' coolant level' written mark ) when i work on my car and have opened an cooling pipe.

[JRTUPIN]

Hello;

The coolant level sensor has been washed ( it was my first hypothesis );and I had put 2 litres in the header tank to full fill it until top ( as indicated on maintenance procedure; but without full fill expansion tank;as stipulated too..)

Now ; after shecking my expansion tank I'm sur that no coolant has been dropped in the expansion tank with warm engine after several fans cycles ( more than 4 cycles).

Any leak can visible on floor or on any hoze after this test ( and no smell of lookant loss)

After test,with engine cold; the coolant level stay at the top of header tank

Engine oil is very clear; without any water include ( the worst situation )

Last month; my Lotus specialist ( well known in Belgium ) didn't find any leak; even after mesuring pressure coolant system fot many hours

You can imagine that I'm a little desapointed..Where the coolant is gone? Do I have a real coolant loss ?

Bye

JRT

[Günter]

i would say: If the coolant level (in cold condition) is on top of the tank there isn't an leak . The header tank cap is an 145kPa type that's correct ! And the expansion tank has an blank type . So have you tried to do it with the 'pre fill method' for the expansion tank ?! I hope none has blocked your expansion tank pipe (as it is fixed onto the main coolant pipe with an plastic strip (on top of the RH frame rail in the wheelarch). I guess that can disturb the normal way of interfering between both tanks... .

Edited June 22, 2008 by G

[Iconic Ride]

Hi again, JR. This is one mysterious problem! Based on your comment about the header tank not getting warm after the engine has reached normal operating temperature and the possiblity that the coolant in not circulating within the header tank itself there could be another factor to consider. Page 64 of the Owner's Manual describes the procedure for "draining/refilling" the cooling system. It is a fairly lengthy process, but the part that deals with bleeding off trapped air in the system makes me wonder if that might be contributing to your problem. Basically, the procedure calls for opening the "refill bleed" at the front of the engine (on the "coolant return" pipe) to release trapped air during a complete system refill, while the engine is cold. Then, after bringing the engine up to normal operating temperature (2 fan cycles I believe) the "radiator bleed" (near the left front wheel arch) is also opened to bleed any further air (this is actually the SECOND time that this bleed is opened during the procedure, the first being when adding the new coolant).

I am not necessarily saying you should do a complete drain/refill, only suggesting that air in the system (as with any car) can be a potential problem, possibly affecting coolant circulation. When your Lotus mechanic did the "presssure check" did he mention anything about opening these bleeds? Just a thought.

Hang in there!

John

[JRTUPIN]

Hello John;

Thank you for your help.

Only the expansion tank stays cold after several radiator fans cycles .The header tank is clearly hot; and thanks god ,there is coolant circulation inside..

I just have opened the radiator bleed as you mentioned ( and as mentioned in owner's manual ). Earing a " spchitt" I guess that there was air inside coolant system.

In this way; I hope now that coolant will be expelled in expansion tank as describe in lotus procedure. ( i Will do the test tomorrow ; for instance, it's too late for engine noice ).

But even with a good result; I'm sure that I have a coolant loss somewhere ( I have added more than 2 litres whitout seeing any coolant expelled during all my tests procedure )

_Engine Oil has been check ( no water inside)

_many Pressure tests have been done by my Lotus mechanic expert ( tests with engine off and many tests with engine on). No lack of pressure detected .

_All hoze clamps are adjustable between expansion and header tanks..

What should I check now?..

Bye

JR

[redshift]

In the header tank there is a level sensor which periodically gets stuck full of muck...........

Thanks for that Kylie, I had exactly that problem last night!

All cleaned out and the light has finally gone off.

[kyliesmith.com]

Little beauty Pete

[Glyn Harper]

This had me confused for months on mine. The same thing. You can keep filling the header tank, and the level will always drop. However, if you leave it for months and check it, it will have never dropped below a certain point. I just live with it!

Gunters fix will probably work, but I just live with the fact the header tank is never at full level.

[leighton]

VERY INTERESTING !!!!

WATER LEVEL SWITCH --- LOTUS PART No A082K6068F

My dashboard level light is intermittently flashing ON/OFF ....

I took out the level switch and washed out a load of brown muck ( seems to be a common problem from what everyone is saying ) ; replaced it on the car and although better , it is still doing it now and again .

Checked water level and there is no water loss at all .

Took it back out and checked the ohmic value - getting silly readings , so i believe that the sensor is faulty.

Does anybody know what readings i should be seeing ?

OR.... before contacting any dealers , is this part available from another vehicle. ?

CHEERS

Edited June 25, 2008 by leighton

[Glyn Harper]

Brown stuff in the water often happens when different types of anti freeze are mixed together. It's not good, as it blocks up your heater matrix.

Always try and stick to the same brand of coolant if you can.

[Iconic Ride]

Hello John;

Thank you for your help.

Only the expansion tank stays cold after several radiator fans cycles .The header tank is clearly hot; and thanks god ,there is coolant circulation inside..

I just have opened the radiator bleed as you mentioned ( and as mentioned in owner's manual ). Earing a " spchitt" I guess that there was air inside coolant system.

In this way; I hope now that coolant will be expelled in expansion tank as describe in lotus procedure. ( i Will do the test tomorrow ; for instance, it's too late for engine noice ).

But even with a good result; I'm sure that I have a coolant loss somewhere ( I have added more than 2 litres whitout seeing any coolant expelled during all my tests procedure )

_Engine Oil has been check ( no water inside)

_many Pressure tests have been done by my Lotus mechanic expert ( tests with engine off and many tests with engine on). No lack of pressure detected .

_All hoze clamps are adjustable between expansion and header tanks..

What should I check now?..

Bye

JR

One other possibilty, J R. I had these exact same symptoms on a different car several years back. Good pressure check, and no fluid beneath the car, but still a definite loss of coolant somewhere. One day, as I was peering into the engine bay with the engine running, I noticed a very tiny stream of coolant emanating from the water pump. This stream evaporated almost instantly on the hot metal of the pump and adjacent engine parts. A short time later the stream reappeared and evaporated just as quickly as before, hence no puddle on the pavement. I now know that the water pump has a "weep hole", and that it was the source of the leak. Replacement of the pump solved the problem. I don't know if all water pumps have this design feature (acts as a "relief valve" of sorts when the pump is malfunctioning), but it might be worth checking into.

John

[kyliesmith.com]

John very possible. I think the whole system needs checking over periodically for leaks. Mines all in parts as we speak !!

[redshift]

The problem is that a 'leak test' may not give the answer.

If the circuit is 100% hydraulic then pressure will drop quickly with any small fluid leak.

Once there is any air in the circuit then any small fluid leak will not show up quickly, if at all.

The TVR is really difficult to purge the circuit of air. If there is an airlock then the result can be as described and the over flow reservoir would dump coolant during the drive (or on switching off) and the level would alway be too low. I guess the Esprit may be the same?

Edited June 26, 2008 by redshift

[txcalypso]

Check the hose at the front of the car that connects the radiator to the cooling system. This is the quickest way for a dealership to drain the coolant and remove the flush. It is possible that the hose clamps were not securely tightened or that this hose has lost flexibility with age and leaks out when it is hot. Just another hose to look at.

[Iconic Ride]

John very possible. I think the whole system needs checking over periodically for leaks. Mines all in parts as we speak !!

This is a problem, Kylie? Simply inform your "better half" that you would like to borrow his Lexus V8 motor (you know, the one that you said was "really loud" in a previous post) from his "project" hotrod. Then head on over to the "General Motoring" thread on "standard or add ons" and show 'em what a REAL "tweak" is all about!

Cheers,

John

Edited June 28, 2008 by Iconic Ride

[Simon350S]

Does anybody know what readings i should be seeing ?

OR.... before contacting any dealers , is this part available from another vehicle. ?

CHEERS

Hi leighton.

Dont know the values but you can get a new sensor quite readily as the sensor and header tank are from a peugeot 205, definately the GTIs anyway.

Pop down your local scrappies, take a look on ebay or even contact peugot..??

Simon

Edited June 27, 2008 by Simon350S

[kyliesmith.com]

This is a problem, Kylie? Simply inform your "better half" that you would like to borrow his Lexus V8 motor (you know, the one that you said was "really loud" in a previous post) from his "project" hotrod. Then head on over to the "General Chat" thread on "modifications" and show 'em what a REAL "tweak" is all about!

Cheers,

John

It does sound quite good !!

Re the parts, I agree with Simon ive just done a google check and off a off a Peugeot 205

[Günter]

google wasn't necessary, it's all well documented [pictured] in our cross reference section