engine and drivetrain Over heating

[Weber1569]

When I use my lights my gauge tells me my engine is over heating, when not using my lights my gauge sits about 2/3 the way up to the red. I checked the temp of the radiator fluid while I was getting these reading and it is about 170- 180 F. Is this a normal temp. and what is the problem with the gauge?

[tony2002]

I'd recently run into the same thing. Flickering gas gauge, temp jumps with lights/directionals. I cleaned up the grounds and it helped a bit. I'm anticipating a proper groundstrap from BLUNTTECH and this may solve the issue.

[Guest Anonymous]

When I use my lights my gauge tells me my engine is over heating, when not using my lights my gauge sits about 2/3 the way up to the red. I checked the temp of the radiator fluid while I was getting these reading and it is about 170- 180 F. Is this a normal temp. and what is the problem with the gauge?

Ever try looking through the archives for you answer?

Common problem. Several solutions. Including this one:

http://www.bmw2002faq.com/component/option,com_forum/Itemid,57/page,viewtopic/t,272816/

Yes, 170-160 Farenheit readings are normal and this too is mentioned in Shop manual, Chiltons, Haynes, Owners Manual, and other posts.

[Guest Anonymous]

Ignore the complaining...

This is most likely grounds that is the problem. Work back from the battery (battery to engine / battery to body/ alternator to engine) and check the state of the grounds (wires connected to the body) under the battery tray, behind the dash and in the trunk. Once these are all tight, rust free and perhaps coated in something such as petroleum jelly or copper grease then look at adding a separate ground strap from the instrument panel to the body.

You might want to remove each fuse, clean the contacts and maybe replace with the correct size fuse as well

[Guest Anonymous]

Once these are all tight, rust free and perhaps coated in something such as petroleum jelly or copper greasel

Copper grease? Do you brew this yourself?

[Guest Anonymous]

http://www.bostik-us.com/files/tdsfiles/NSRegular.pdf#Regular

Known as Copaslip in the UK. Good for your battery terminals as well

[Guest Anonymous]

Once you've eliminated the ghosts in your instrumentation with proper groundstraps look at the typical causes for engine overheating. What is the rating on your thermostat? BMW makes at least three temperature ranges. Put in lower temp thermostat and system temp should decrease. Another thing, if youre running coolant in your radiator, you might try going to a 50/50 mix or lower. Water cools better than coolant. Make sure your timing isn't too advanced. Hot timing makes for hotter engine. Turn on your heater and feel how hot the air is blowing. Hot air means hot engine. Cooler air with overtemp reading on guage indicates something wrong with guage. Is temp sender stock?

[Weber1569]

I do not know what the rating on my thermostat is. How do I find this out? And how do I know if my temp. sender is stock?

[TobyB]

No, if you really have 170- 180 water at the top of the rad, you have a

gauge problem, not an overheating problem.

And you probably have a 175f t- stat, and almost certainly a stock sender.

There are a few grounds that will do this- engine to body, alternator to engine, battery to body

and gauge to body. There's a writeup, but the short version is that

you just make a ground strap that connects the nuts on the

back of the water and fuel gauge to the body.

Everything else is just making sure the factory grounds are good-

really tug on them, because they can rot on the inside of the crimp

and look great. But not conduct well at all.

If you know how to use a voltmeter, it's fun to meter across all

the grounds to see if there's any voltage across what you think

is a solid wire. Tells a lot in a hurry.

good luck.

t