Ineffective heater ....brrrrr

[Guest modifiedv8engines]

Car originaly had a/c which was removed when I installed a HD coolant rad and wanted more space for a planned intercooler installation.

Cooling system is bled correctly but with temps of 80 - 85 deg C the blower is only blowing out tepid air onto the screen - maybe the factory system was just an old/poor design or should the blower be pumping out much warmer /hot air ???

Estimate warm is is about 50 - 60 deg F or about 15 - 17 deg C or thereabouts

No doubt something wrong and or impossble to access !

 

 

[sailorbob]

When working correctly the interior heater system is more than capable of warming the cabin. See http://www.thelotusforums.com/forums/topic/77978-esprit-heater/ for a few ideas on what may be wrong.

[oneshot]

Even in the depths of winter I cannot have mine on full heat as it get's too hot in the cabin. The heater is certainly up to the job so you have a problem somewhere.

[Guest modifiedv8engines]

Thanks for the link Derek and to you Dave for confirming what temps should be expected.

Much appriciated

 

[Guest modifiedv8engines]

Bit further forward -

Out for a run today about 25 miles and temp gauge isnt going much above 70 deg C meaning no full boost etc etc and still no warm air in the cabin.

Checked the n/s/r (above fuel tank) vacuum connections to the solenoid and although one of the 90 deg rubber connectors had started to split nothing obvious to report ie not leaking

Also managed to squeeze the top half of my carcass upside down into the drivers side footwell to inspect the vacuum connections there - all seems okay.

Seems as though its the diverter valve ( front of chassis) or possibly the thermostat ?

With engine cold ( this evening) start engine and the near side (LHS) rubber hose is getting warm after a few minutes running. This pipe joins a alloy tube with an upward branch which I assume goes to the heater matrix ? The small diameter hose which joins the alloy connector tube is stone cold. 

Thoughts are that this hose about 50mm diameter should be cold until the thermostat opens and then allow coolant to flow and through to the radiator. Seems though its the thermostat thats stuck open 

Can anyone confirm whether my findings are consistant with a stuck open stat ??

Cheers

Paul

 

 

 

 

[Bibs]

Sounds like it, does it take ages to get to 70^o?

[Guest modifiedv8engines]

Seems to take a fair while to get to 70 Deg C Bibs.

Always like to warm the engine before moving off to prevent excessive oil pressure etc etc. If the car is left idling for say 10 mins it reads 70 ish on the gauge but as soon as you drive and with air cooling the rad, the temp drops again to below 70.

Give the car some stick and say hit 100 - 120 MPH for short bursts the temp rises but never goes much past 70 - 75 deg c and then when crusing at normal speeds, temp drops to below 70. Gauge is a bit inaccurate as determined by Peter Es software but can report full boost is not available due to low coolant temps. Car is quickbut not as it should be 

In traffic it will hit 90 + C and fans kick in and once on the move again the temp drops again to below 70. If you boot it as the temps droping full boost is available. 

Chances are its the stat but better to get some feedback before spending an a few hours with my arse stuck up in the air in the engine bay.

 

[Bibs]

Sounds very much like the stat. Cheap and easy fix  

PS better for the engine to jump in and drive. Letting it warm up idling creates more wear...  

[superdavelotus]

Hi Paul,

It's definitely your thermostat for starters. I would recommend only fitting a genuine Lotus one on the V8 as I've heard others would start to play up after a short while (these are the words of a well known independent not mine).

If you are still have problems then look at your diverter valve. This is providing your car runs up to temperature within 5-10 minutes past 82-85 then drops down to say 80. This will confirm that your thermostat is working correctly. Feel the right hand water pipe coming in on the driver's side footwell. If it's cold then try pumping the pipe with your hand to see if any heat starts to come through. If you can get heat coming through pipe then it's likely to be your heater matrix is blocked. This will require a combination of pressure and reverse back flushing by disconnecting the heater pipes from under car near front cross member. If you don't get any heat coming through then it will be your diverter valve. This can either be no vacuum operating this and you can confirm this by attaching a manual pump to the vac port and operating yourself or a seized valve. You may be able to free this valve but it's likely you'll need a new one.

 

Regards,

 

David Walters

[steve930]

Yep agreed, sounds like stat. Mine runs at 85 - 87℃ in average conditions 

[Guest modifiedv8engines]

Thanks for the tip Bibs but always prefer to get the oil warm so it thins and coats the bearings/journals better. Differntial expansion of materials ie steel and aluminium generaly means both materials need to be up to temperature for correct operation of the restpective components. Manufacturers of new vehicles like you said recommend a get and and go but tend not tto explain that oil, coolant needs a bit of time to circulate

My long warm up times (excessive) are in an attempt to get some heat in the cabin and to assist with the engine managements defense mechanisms ie enable full boost which I seem to recall is not available until engine temps hit 80 + deg. Low temps = low boost 

Useful tip on the Thermostat David -

Will get one ordered today and the "O" rings to eliminate this component from the problem.

Driver side wheel arch pipe to rad gets warm and you can feel the pump pulsing coolant through the system.  

Thermostat first and Diverter valve or back flushing the heater matrix next

Thanks again for your assistance

[Chillidoggy]

Paul, the way you're warming your engine up you're probably increasing your engine wear. Today's oils are already thin enough at low temperature to provide the necessary protection in respect of circulation. You'd be much better advised to move off as soon as possible, keeping it under light loads until it's properly warm, before using the full performance.

[Bibs]

Exactly that.  

 

[Guest modifiedv8engines]

Like I said above ....

"My long warm up times (excessive) are in an attempt to get some heat in the cabin and to assist with the engine managements defense mechanisms ie enable full boost which I seem to recall is not available until engine temps hit 80 + deg."

Think more potential damage would be caused by booting the car up the road and then finding out what I already know i.e., that theres something wrong with the cooling system !

The long warm up times are not the norm but an attempt to get the engine actualy warm and not excessively cooled which would/does occur if the car is started and driven straight away.

 

[Guest modifiedv8engines]

And ....having dismantled probably in excess of 200 V8 engines over the years and seen first hand where flat tappet cam engines fail, and  where the manufacture has recommended a synthetic oil in an engine that was originaly designed to accept thicker oils.....I will stick with what Ive observed. 

Sure, these are an older design of V8 engine but thay seem to last a few more miles than our cars before they need work. Note the recommeded oils for these engines do not have high ppm Zn content which they cannot of course due to catalytic converter failures.

Low Zn = greater engine wear

High concentration of Zn = reduced engine wear  

Thanks for the input all the same

 

[Chillidoggy]

It's your funeral.

[Guest modifiedv8engines]

Ian

For starters I think you have not read or taken my mesage out of context. The long warm up time was/is to determine whats was going on with the cooling system. Typicaly I do with this with particular engine make sure the temp gauge is starting to move before driving. 

Consider the fuel/air mixture entering the combustion chamber on a cold engine and that the piston rings not up to temp or the cast, hypereutectic or forged pistons ( typicaly made from an aluminium alloy) have not reached operating temperatures (expanded). The gaps tend to reduce as the engine warms as coolant and the heat from combustion warms the usualy cast steel or nickasil coated cylinder block liners

Typicaly engine maps are confured to prevent stalling which usualy mean a rich mixture. Then consider the combustion charge as it blows by the rings as its inevitable that some will and the droplets of fuel in the form of blow by gas enter the sump/oil/lubrication system and then on to "lubricate" the bearings.

Expect you may not have seen bearings from high milage, hard used or race engines where fuel has contaminated the oil that is lubricating the engine. I have and also seen and inspected crankshaft journals where for example engine a/f mixtures are excessively rich. 

Tell me when you drain your engine oil, is it like it was when first you first filled it with fresh oil or is it dirty, smelling of fuel and contaminated. If its contaminated then I would suggest that the products of combustion are finding there way into your engine oil. And they will be

Frequent oil changes and good quality filters with careful warm up will result in a longer lasting engine.

Can if you like carry out an oil analysis on your used engine oil using your start and go method and then again with fresh oil and see if the level of contaminants is greater or less with each method. Several companies now offer this service as a preventative measure and so they can establish engine wear on various machines in industry.

 

[superdavelotus]

Anyway, Did you make any progress on your heater system?

Lets try and keep this on topic for the sake of others who may have the same problem and want to search this thread in the future.

 

Regards,

 

David

[Guest modifiedv8engines]

Good idea Dave.

I do wish readers would read the messages (like you did) rather than commenting on unrelated topics which of course the contributor is obliged to explain in more detail !

Have a thermostat on order from Strattons which should be in on Friday. Think your suggestion of this item being the culprit is the most likely so will fit that, report back with my findings and hopefuly this will be of some use to others.

Paul

[Guest modifiedv8engines]

As per Davids recommendations...

Thermostat replaced and can report that engine warm up times are much quicker with the gauge showing just under 90 deg. Engine feels smoother and although some warm air is coming into the cabin, its warm then tails off to cool so will need to bleed the cooling system as I expect there is an air lock ( failing light and rain prevented completion)

Old thermostat was stuck closed and failed to open even with boiling water from the kettle....

 

[superdavelotus]

Hi Paul,

It could be an air lock like you say. I would guess and say it's either that or heater matrix is starting to block. I would try pumping the right hand pipe in the driver's side footwell and see if you can get any heat to start coming though. This is what happened to mine and it gradually got worse until I had the heater system back flushed with combination or pressure line and water.

Regards,

 

David

[Guest modifiedv8engines]

Hi David and thanks for the tip Re:  the rad nose & heater matrix.

Went out to the car this afternoon ( engine stone cold) and loosened the radiator bleed with header tank cap removed. Steady stream of coolant and  a few farts and belches as some air exited the top of the radiator. Tighten up rad bleed, top up with water and out for a short drive.

Super quick to warm up and temp gauge sitting @ around 90 deg C and warm air at last from the vents .

Brilliant !! ......and best of all is the car pulls wonderfuly and is quicker than it ever has been. Feels like another 50-60BHP has been released.

Really is that much different to drive so can conclude that your original diagnosis was correct and since the engine is at the correct operating temperature, this means the ECU is doing what it is supposed to and giving the correct fuel, sparks and boost from the turbos. 

The £30 quid thermostat was expensive for what it is but probably the best 30 quid Ive spent on this car. 

Interestingly, the scan tool data for temp ( thanks again Peter) is pretty much as the gauge says and not a difference of 10 degrees which I had before and just put down to the gauge being tired.

Well pleased

Cheers

Paul

 

 

 

 

 

 

 

[stugilmour]

Paul, I want to attempt to bleed my radiator for the first time; my previously aftermarket radiator did not have a bleed so have never done it before.  I take it has an Allen head plug up there, similar to the plug by the thermostat housing?  Is it the same size Allen wrench as the engine plug?

My heater core required back flushing, which turned out to be not that difficult to do without draining the entire system.  As not much visible stuff came out, I am thinking it may have just assisted in freeing up the temp control valve.  Whatever, the heat performance is way better; working sufficiently at 0 degrees C and the window open!  

Thanks & congrats on a job well done.

Stu

[superdavelotus]

That's great news Paul, that you are now sorted. A bonus that your car feels better and power is back to where it should have been!