'86 overheating?

[cookieguy]

Hello, I've just bought an '86 Turbo Esprit which had a total engine rebuild (including pretty much everything else) abot 3 years ago.

My concern is this, the temp and fuel gauge work intermittently and I'm having the voltage stabilizer replaced next week. What concerns me is that when the temp gauge does work, it shows the temp to be just under the 140 mark, obviously very high.

Could it be that the gauge is not quite telling the truth (I hope so) or am I running hot?

What's the best way to find out before I have the gauges fixed? Is there a way to check if it is too hot or not?

There doesn't seem to be anything untoward occurring in the engine bay, no boiling,bubbling or burning smells, but the last thing I want to do is fry the engine!! LOL

I'm not the most mechanically minded person, but I like to know what's going on under the hood! I look forward to your input

Adam

[andydclements]

Purchase/ borrow an infra-red thermometer, with the car warming up (not fully hot just in case) compare the readings on the dash with the reading when you aim at the ali pipe in the engine bay where the temp sender is (top of engine near the cam belt).

If the readings are the same at an indicated 80-90 C then a reading on the dial of 140 is something to worry about.

If the infra-red one gives something liken 60C when the dash indicated 100C, then 140 probably isn't too bad.

I cannot recall for certain, but if the temp gauge is also calibrated for 10v (what the stabiliser does is turn 12v constant DC into square wave 12v DC with an RMS of 10v) then that would cause the false reading.

[comem47]

I know in the case of the S2 (Smiths gauges) that the voltage stabilizer is physically mounted to one terminal on the rear of the temp gauge. While I threatened to replace it with a solid state device, all it took was a snap from my tumb releasing the index finger fingernail to "twap" the glass face over the temp gauge and the stabilizer fell into submission from the mechanical jolt ;-) I quickly saw(well it is damped, so not that quick) the temp go down along with fuel going from about 2/3 full to the correct 1/3 full (roughly from memory). It's behaved all these years since. When the stabilizer sticks high (14Volts) you will see this behavior. Why Lotus used that piece of crap vs solid state is is beyond me (no it isn't, we're talking about saving pennies and they likely got the parts for free from someone else throwing them out!!! ;-)

Edited May 28, 2010 by comem47

[cookieguy]

UPDATE:

Today I drove the Esprit around town for a good hour or so and lo' and behold....the gauges behaved for a while!

How pleased was I when the temp gauge settled just above the 75 line for the journey!!!PHEW The fuel gauge showing 3/4 full (about right)

Then out of the blue, both needles pegged out!!

So it would indeed seem to be the voltage stabilizer playing a cruel trick on me!

Oh well, better safe than sorry!

On a different tangent, the radio antenna decided to have a fit and rise up and down at random when I had the radio on! It hasn't done that before?? Any suggestions? LOL

Adam

[FRANTIC FRANC]

sounds more like an earth fault.

[stevem]

I had a similar problem when I first got my 88 esprit, the radio would turn off when the headlights were on and the needles on the gauges were very eratic. It turned out to be a bad earth.

Try clipping a black jump lead onto the -ve of the battery and connecting the other end onto the earth strap in the drivers door hinge area. That might give you a good solid earth to use whilst testing. If it fixes the problem then run a new earth cable to the binnacle/scuttle/door hinge area. ( somewhere solid up front ) Something about 8 or 10mm should be OK.

Does your dash have a volt meter ? You should see it come up a volt or two if that's the problem.

Edited May 31, 2010 by stevem

[cookieguy]

Just had the new voltage stabilizer fitted and I'm still getting intermittent gauge readings *SIGH*

So, a couple of folks thought it may be a bad earth, where do I look for that earth connection to check it?

It's starting to bug me now! LOL

Adam

[hotsv1]

damn... sound like my problem too... rear plate light flashing when indicator is on, and my guages does the same thing too!! >< typical esprit problem?

[86esprits3]

I do know that the voltage stabilizer for that gauge looks like it was made in 1910! It is a piece of metal that changes with heat, and I think it cuts out a thermal switch. I replaced my gauge with a new modern one and took the thermostat sender out of the car and verified it with an accurate thermometer in hot water to make sure the gauge was reading correctly. My inaccurate gauge problems where solved. Then I drilled a hole in the face of the gauge and inserted a small green LED. I wired this into the radiator fan circuit. it worked great! When the fans turned on, so did the green led in the dial of the temp gauge. When I was driving on a hot day, I had no doubt to whether the fans where spinning or not.

[andydclements]

The voltagge stabiliser for the Lucas kit is a bit of a breach of the trades descriptions act, instead of stabilising the voltage it works on producing a square wave DC supply that has a Route Mean Square of 10v.

It cuts the supply momentarily, returns it to 12v (or whatever the alternator achieves above this) then cuts the supply again, achieving an supply that would average out the same as a constant 10v one.