Esprit (S4s) running temperature

[azachlod]

I've always known both my '79 Esprit S2 and '95 Esprit S4s to run hot, but I thought it'd be a good idea to check with other owners on what "normal" operating temperatures for the Esprit seemed to be...

The thermostat in the '95 S4s hits 90 before the radiator fans kick in. They blow for a minute or two and then switch off - with no decrease in the temperature indicated on the thermostat. Now a few minutes later, and a guage bars width over 90, the fans kick in once again. The temperature at idle seems to sit around this 90 mark.

This is at idle. On a hot day while driving it can go up just under the start of the redline bar. Traffic jams make me nervous.

I've seen various comments about pulling over and letting the engine cool and various Lotus mechanics have said the same, but I was wondering of this is normal. I'd rather hear from fellow Lotus drivers as opposed to the guys who are jumping at the chance to have to rebuild my engine.

[ErnestM]

I believe 87 to 90 is normal operating range. That is where my V8 runs. Sorry don't know much about S4's...

ErnestM

[GUY JOHNSON]

Sound like you might have a problem with your thermostat., and the sending unit.

[MikeyRide]

FWIW, I've sat idling in >90F heat with the AC on and my S4s was stable at 95C according to Freescan. A track day with similar air temps had the car right at 90 after a cooldown lap, again using Freescan. I do run Redline Water Wetter but don't have any before/after data to offer.

I recently installed a later rev of the chip from Andy Whittaker and the fans come on earlier. Too early for my 88C thermostat, in fact.

[cnh1990]

My car runs at 82c, fans kick in high just below 100c temps drop down to 82c then the fans switch off. If you get nervous force the fans to come on by turning on the A/C even if you don't need it for interior cooling the fans will come on.
Calvin 90 SE

[5150neo]

Last month I found a few hoses that needed replacing. As preventative step I decided to upgrade all hoses to Aeroquip socketless type hose. Before this upgrade my average temps were 84 to 90. On hot days the temp would reach almost 100 before the fans would kick on. Since the upgrades the temp has not exceeded 90C even in 92F weather. When was the last time you had the cooling sys flushed and refilled?

[Skerd]

I had this identical problem with my S4s and
there is definetly someting wrong with your
cooling system. My problem was the radiator
was clogged and one of the radiator fans was
not working. My dealer said the radiator is
notorious for gunking up and limiting the
flow of coolant. When they took the radiator
out, it literally fell apart in their hands.
My temperature gauge was always near/in the red
before this replacement. Now the temperature
needle sticks straight up (75C) and whenever it
approaches the start of the red part the fans
come on immediately. It has never gone into the
red now even after a 30 minute barely moving
traffic jam. The new radiator/fans are expensive,
around $ 1,500 plus.

[azachlod]

The cooling system was flushed last year around this time since it looked a bit "icky" according to the mechanic at Rothrock in PA. I did verify that all 3 fans are working when they kick in at the 90+ mark. I'll try some Water Wetter until I get someone to thoroughly check the cooling system once again.

Thanks for the tip about the AC - I never used it so I would've never noticed any cooling benefits.

I'm in Connectcut and Valenti Motors no longer services Lotus unless you bought the auto from them, which I did not. I must have scared them off a few years back when they did some electrical work on my '79 S2. I have the Speedvision mechanic in Stratford and a few others that *can* do the work, but does any New Englander have any "authorized" mechanic/dealer suggestions? I think Mass. is my closest option.

Thanks for the replies all!