What should the engine temp. gauge read on a calm, cool, autumn drive in a 150-S? How much should the gauge move around?

D. J. Lokun

Submitted by NC43-62049 on Tue, 09/30/2008 - 13:30

Friday past ... all day run ... twisty roads .... all seems well ... temp stayed in 70-80 range ...... what a great car!

D L

Submitted by NC43-62049 on Tue, 09/30/2008 - 13:29

Edited on 2008-09-30 13:33:20

Friday past ... all day run ... twisty roads .... all seems well ... temp stayed in 70-80 range ...... what a great car even if not a showable Concours car!

D L

Submitted by NC43-62049 on Wed, 09/24/2008 - 16:58

I guess I was getting a little panicky when it reached 90 because I was running out of numbers.
D Lokun

Submitted by rmurray@turfpr… on Wed, 09/24/2008 - 14:11

my 150 3.4 runs at 80-85 most of the time. If stuck in traffic it will slowly rise to low 90s. once underway again back down to that low 80. On a cool crisp day in southern Maine running without trffic it will be in high 70s

Submitted by NC43-62049 on Wed, 09/24/2008 - 13:50

Edited on 2008-09-25 19:26:14

Thanks muchly. Answers like this make the fourm(s) invaluable. I am embarking on a country roads test run Friday so wish me luck.

D L

Submitted by SE98-32482CJ on Wed, 09/24/2008 - 08:08

That sounds very reasonable--you see the temp while parked as it is a direct mechanical feed and is not damped as in your XJS (XJ-S). The outside temp ,unless extreme has little effect on your readings unless you run w/o a thermostat and your stated readings are normal--in fact any lower than 70c and I would be concerned about too cool running. The engine needs heat to burn well. Since you said you had points trouble at this point I would check tune before I messed with the cooling system. You stated you had an uprated fan which is usless on a 150 without the proper fan shrouds which are missing on a lot of cars. Good luck!

Submitted by NC43-62049 on Tue, 09/23/2008 - 17:06

Edited on 2008-09-23 17:10:47

Prompt reply or what? That's a great thing about this web.

Driving in Great Lakes area where it is autumn.

Disconcerting to see temp rising and falling ... I am used XJ-S where the temp gauge never-ever moves ...

150 running temp was in the 70s although day was cloudly and very cool (60s?) .... rose to 80s when cooling off while parked .... Creeping traffic caused readings in the high 80s ... Back down in the 70s with speed and resultant air flow... not completely sure about readings as I also trying to enjoy the view .... needle creeps up and down (i.e. not a jumpy needle) ... oil read was rock solid ... car has an upgraded fan ... Last week's trip was a total bust out due to points and other electrical issues which now appear "sorted" (yea right). I would not be surprised to see temp reads of 90 on a "long" trip. Mayhaps a cooling system revisit is in order.

Best part of the day? Keeping up with a Prowler in a 49 year old car.

D L

Submitted by SE98-32482CJ on Tue, 09/23/2008 - 16:24

Well Dan you have not been clear where you are driving but as a very general rule if I saw more than 90 c on a cool day even traffic I would start checking things! As far as moving the gauge is fed by a bulb and it should not move fast in either direction--what are your readings?