Running hot - any advice?

[Europa73]

Hi all,

Just took the TCS out for the first time - and - my first time in a moving Europa - WOW

But - its running hot - needle settling around the marker to the right of 90.

During the restoration I did take off the swirl pot for painting.

The hose coming out of the engine (by the thermostat) is very hot - but - the hoses at the radiator are nowhere near as hot.

Could this mean the rad needs bleeding?

Any advice would be greatly appreciated.

Thanks,

[BDA]

If in doubt, I would burp the radiator (again). It doesn't seem like your thermostat is bad but you could when it opens (you can use a thermometer and a pot of water on your stove). I would also note that the mark past the 90° mark (see the graphic I've attached) is not THAT hot. I have a fan controller and a radiator fan switch. I tried the radiator fan switch for a change it it got as hot as you describe. I thought it wasn't working but the fan kicked in a short while later and cooled it down to about 90°. I decided to use the controller but the fan switch can be wired up easily for backup. I only mention this in case that is the way your fan switch works. I don't remember it behaving that way way back when the car was new. There are also products like Red Line's Water Wetter that helps the water stay in contact with the radiator and helps reduce your temps.


I'm assuming your ignition timing and fuel mixture are reasonably close (not too advanced or lean), that you have enough coolant, and that your water pump is working (proper belt turning the pump, the pump isn't showing signs of distress like leaking water).


Everybody complains about the cooling system in a Europa. I certainly wouldn't say it's over designed but I lived in New Orleans and when it was new, I drove through the Nevada desert in the afternoon (trust me, you don't want to try that) and I don't remember having any cooling issues. I would say the stock system is adequate. You can help yourself with an aluminum radiator and a high CFM fan (I did) if you feel you need it.

[BERNIEHUMBER]

HI:I had an issue with my S2.The rad has a baffle in it about 1/2 way down that forces the water(coolant) to circulate properly.Mine had come loose and coolant was in effect bypassing part of the rad.
I was worried that I had a bad head gasket !!

[EuropaTC]

Hi there,

As BDA shows, the recommendations from Lotus themselves do show quite a variation and from what I recall the stromberg engine versions did run at slightly higher temperatures so I wouldn't get too wound up unless the engine was clearly boiling and blowing water out.

However....    I've usually had to bleed the radiator at the front to remove some trapped air so if you've not done so, that's the first job. Also check the heater is working, not so much to keep your toes warm but to ensure that water does circulate around the pipes and there's no air lock. I usually find that slowly filling the system with the engine running takes care of that aspect, but it's worth checking because if by some chance you had a lock on initial filling then you might find you're a bit down on total coolant.

If the coolant volumes are about right, there's no air locks and you're still concerned then I would check the gauge/sender combination.  In my notes I have a page where someone measured the voltages/resistances of the Europa gauge/senders but unfortunately I've just checked and the original is no longer there. So with cut'n'paste here's the data for the temperature gauge.

Temperature gauge

Temperature   Voltage      Current   Sender Resistance   Sender Voltage
(C/F)             (volts)      (ma)           (Ohms)         (volts)   

70/158      3.05              51.3           135.5         6.95
90/194      4.31              72.2           78.8                 5.69
100/212      5.15              85.7           56.6                 4.85
130/266      6.55              107.8   32.0                 3.45

This data is for the S2 but.....  the S2 & TC have similar numerical part numbers and so it might be useful as a starting point.  When I had cooling problems (before finding this chart) I simply took out the sender, wired it up with extension leads and popped it in a kettle of water. When it boiled, I checked the gauge reading to see where 100C came, which was pretty much on the mark to the right of the 90deg. figure. At least that way you'll be certain when the engine is approaching boiling although in my experience it's clearly unhappy and throwing water out when something is wrong.

Brian

[Europa73]

Many thanks for all the grate advice.

Much appreciated!

[Grumblebuns]

I don't know how long your TCS was sitting but make sure that your coolant pipes and radiator are free of rust and crud. When I started up my S2 for the first time after sitting for several years, I immediately plugged up my radiator with the rust that had settled in the low points of my coolant pipes. I would back flush the radiator and run a garden hose through the pipes with the hoses disconnected from the radiator. You will at least know that your problem is not a flow issue.

[Europa73]

thanks - will do

Sounds like a fun job :-(

[Europa73]

Hi all,

i hope this is not going to be bad news.   

I bled the rad - flushed the pipes and the car is still running hot.

needle resting on the 1 of the 130 on the temperature gauge.

I have no leaking from the water pump - and the heater works well.

I did notice that the rad is very slow to heat up and the top hose next the the thermostat housing is way hotter than the hose at the front of the engine.

Is there a way to test my water pump is operating correctly

Second I will test the thermostat - any advise on what thermostat and gasket it uses in the TCS

Many thanks,

[Europa73]

just repeatedly tested the thermostat - and it opens wide up in boiling water.

next test the sender.

any thoughts anyone?

[BDA]

IIRC, the thermostat is marked for when it opens. I would check that it opened at the right temp, but since it opens by 100°C, that isn't the cause of your overheating. If it's not opening soon enough, it may not be helping you as much as it should but I think the failure mode is not to open rather than at the wrong temp.


Testing the sender is a good idea.


I'm sure someone out there has a better idea, but you could test your water pump by taking out the thermostat and pulling the top radiator hose. When the motor is running, it should pump water out of the radiator (somebody please correct me if I'm wrong - but either way, you'll see movement somewhere quickly if it works!).


Are the rest of your gauges behaving properly. If not, I think your voltage stabilizer could be causing you trouble. Here's a link that might be helpful: http://www.minimania.com/Smiths_Voltage_Stabilizers

[jbcollier]

What is the temperature rating of there thermostat?  Use a cooking thermometer and check and see when it actually opens.

[EuropaTC]

I have no leaking from the water pump - and the heater works well.

I'd take that as a positive, if the heater is working then I'd be 99% convinced the water pump was doing it's job as well. The feed/returns for the heater are only 1/2" pipes and so I'd be very surprised if that would operate by thermosyphon alone, I think given the layout it will need some pressure from the pump.

I did notice that the rad is very slow to heat up and the top hose next the the thermostat housing is way hotter than the hose at the front of the engine.

Is there a way to test my water pump is operating correctly

Now I haven't tested mine, but I'd expect the top hose to be significantly hotter than the one into the front cover plate, that should be the return from the radiator.  I would expect to feel a notable difference between the top and bottom hoses of the radiator as well.

As for testing the pump I think that's a bit more complex. I can think of checking the drive belt is good and turning the pump with no slippage, but after that I'm not sure of any definitive tests you could do easily. It's a simple design and if it's not leaking then the only way it can't work is if the impeller has broken up (noisy, wouldn't turn) or is slipping on the shaft. That actually happened on mine, but it was my first replacement pump and with hindsight it did press onto the shaft with little pressure; we put it down to not being machined correctly because the second one was much tighter and is still there today.  I can't imagine that's the problem with yours.

Perhaps with the thermostat removed and the radiator cap off the header tank you might see some level movement if you flicked the engine from tickover to say 3,000rpm rapidly ?  I'm clutching at straws really.

My thoughts are with BDA, check the instruments.  I'd put a meter between the regulator and gauge to see if it's getting 10v or 12v. Incidentally, is the fuel gauge about right or is that also reading higher than expected ?  (same feed)

As for the sender, it's easy to see if one has failed completely because it will have virtually zero resistance & go directly to earth/full scale deflection on the gauge. One that's partially failed is harder to spot without checking the resistance vs temperature. There's also a chance you have the wrong sender for the gauge, I think they do come in different resistances ?

[Pfreen]

I would buy and use an infrared temperature gun.  You can use it to measure the temperatures throughout the cooling system.  I made a variable voltage voltage stabilizer so that I could calibrate the temperature gauge.  It read about 15 degrees high with the original voltage stabilizer.

The voltage stabilzer voltage directly affects the temperature gauge reading so it may be your problem if your temperature gun shows that the temperatures are actually normal.

[Europa73]

Temperature gun -thats a great idea!

[Grumblebuns]

If you use an IR thermometer gun, make sure that you are using it correctly to get accurate and consistent readings. I failed to read the gun instructions and kept getting inconsistent and wrong temperature readings. Couldn't figure out the reason and blamed the gun instead of the user. The link below has a good explanation of why working distance is critical.

http://en-us.fluke.com/community/fluke-news-plus/temperature/how-to-get-great-results-with-an-infrared-thermometer.html