My temp gauge stopped working today. I don't have a mech radiator fan, only the aux fan and it doesn't kick in now. The aux fan does work when hooked up directly to the battery, but it won't otherwise. I get voltage to two pins of the connectors behind the dash, but I don't know what they are for.
Any ideas of what should I look at?

Maybe the sender in the head? You dont have the standard belt driven fan? aux fan, you dont mean the one for the AC?

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

hit your dash and see if it pops up.

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1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg

I guess that's the a/c fan. I guess it was wired by the PO to kick in when it got too hot. How do I know if the sender unit is bad?
The needle moves a little when I put the key n the on possition.

I just noticed that the fan actually does work. Now I jut need to know how to fix the gauge.. how can I check the sender unit?

I just had this problem on my '81 wagon and it was the sender. I just pulled one off another engine I had out back. Others might have info on resistance readings but I can't remember what they were.

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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

As I remember if there is NO resistance, its bad but I'm not sure, I would just pick up a new one, they are only about $10.

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

I changed the sender with a new one but made no difference. Any ideas???

Maybe find another gauge at the wrecking yard or eBay and swap it in.

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

The coolant temp sender(a NTC resistor type) will have the resistance readings(roughly) as follows:
37@ 100 C
50 Ohm @90 Celsius
67 @80
94 @70
135 @ 60
160 @ 50

The gauge is electric, so maybe there is a ground problem. the three gauges, clock or tach w/clock, spedo and the tri gauge on the left all overlap each other. this where each one grounds together. maybe there is some corrosion between them.

Pull the instrument cluster and lightly clean the contact areas.

there is also the ground connection I believe behind the inst. cluster where a bunch of brown wires come together.

remove the oil line with a 10mm and a 13mm.

do not start the engine with this line not connected.
you will be surprised with black oil gushing on you and everything.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Good idea on the ground,

What you might be able to do is add a ground to the"gauge cluster" (mounting screws). I've never tried it but it might be possible without removing the instrument cluster. Remove the plastic panel above your knees, and have a look.

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"