Series 3 Should the temperature gauge usually move much when driving?

I took my Series 3 2 1/4 Diesel on its first proper run since I rebuilt it today.

I did sixty miles in all, with 50 or more of those miles being at 50mph.

Something I noticed was that the temperature gauge did seem to move a fair bit.

When running for a while it would hit about 2/3rds of the way up the gauge and stay there, but would drop when driving with the engine at lower RPM.

Is this normal for a Series? I'm comparing it to modern cars where the gauge usually sits at a certain point once the engine is warm and doesn't change much.

Thanks for any replies.

mine sits once warm s3 diesel same as yours

Should sit around the N mark. The gauges aren't particularly accurate just a rough estimate. As long as it's not overheating and not running too cool then there isn't a problem.
Not best to rely on the original gauges really use them as a ballpark figure but now you can get aftermarket temperature gauges that are very accurate.

Get an old school mechanical gauge - £30.00 or so, accurate, sorted....................

Can indicate the thermostat opening and closing when it moves like that, can also indicate an airlock, can also be faulty voltage regulator if fitted behind the dash

Sounds like you have no stat or its stuck open....should stay steady.

Mine is always in the same spot, at the bottom because it's broken

In all seriousness they are so delayed that when they are at the top it can be too late.

Thanks for the replies.

I know that the thermostat is there because I saw it when I fitted the radiator hose.

How would I go about testing the voltage regulator?

Voltage reg feeds the temp gauge and fuel gauge - if one is moving about the other will be too.

Get a proper one..................................

I have always found them accurate and reliable.

I bought a hand held infra red temp gauge...very handy or testing like you are doing...arond a tenner on ebay.

Maybe your pump timing is to far advanced...so many things...even your rad could be part blocked.

Nick.

Mine usually stays on N but I noticed it dropping back today due probably to the strong winds

Thanks for the replies.

The fuel gauge stays steady (apart from the needle vibrating at certain speeds).

Does advanced pump timing cause the engine to heat up more than it should?

What make of aftermarket temp gauge would be a good one to use?

Durite or Tim mechanical gauge - you may need an adaptor bush as well - supplier should be able to advise. It has a bulb shaped sender then a fairly solid wire to the back of the gauge. You can't cut the wire or bend it too sharply - route it away from direct heat so not touching exhaust etc. A bit of a fiddle to fit but once done it'll work forever...............................

My std gauge has so far given my 40 years of trouble free motoring...spend you dosh on a infra red one for testing...so handy for testing all kinds.

nickjaxe said:

My std gauge has so far given my 40 years of trouble free motoring...spend you dosh on a infra red one for testing...so handy for testing all kinds.

Click to expand...

That just means you've been lucky - not that originals are any good! but each to their own - I like to know exactly what's going on and not rely on 40 year old wiring/gauge/v.regulater/bad earth etc. Mechanical gauge replaces all that in one hit................................. your infra red is a handy tool but aint going to tell you what's happening as you drive.

My std gauge will show me a trend...and I can test its accuracy with the infra red...as you say each to there own.
I like to keep my LR as std as poss...within reason.

Granted - but an extra gauge or two isn't an irreversible mod and the extra peace of mind is worthwhile IMHO - I also have mech oil pressure - you'd be amazed at how low it has to be before the light comes on..................

Yes I have one of those as well...as you say very worthwhile...use to have an amp meter...replaced that with a batt condition meter.