1984 300SD water sender ohms?

[marybeth]

I am the proud owner of a Dodge Durango that has a transplanted 1984 300SD MB engine in it. Only issue is the Water Temp guage is not compatible with the MB Temp sender.

Anyone know what the spec are on the MB water temp sender or an aftermarket Water temp guage that will work with the stock MB Temp sender?

[mach4]

Originally Posted by marybeth

I am the proud owner of a Dodge Durango that has a transplanted 1984 300SD MB engine in it. Only issue is the Water Temp guage is not compatible with the MB Temp sender.

Anyone know what the spec are on the MB water temp sender or an aftermarket Water temp guage that will work with the stock MB Temp sender?

The ohms on a sender vary with temperature - a temp gauge is therefore calibrated with temperature markings that correspond to the sender's reading based on the ohms at that temperature. The easiest solution is to get a Durango sender and mount that in the 617. You've got several choices of where, each of which will likely involve drilling and tapping to accommodate the Durango sender.

The thermostat housing looks like a good candidate as it appears that there is enough material there to drill and tap to 3/8NPT. You can probably find a compatible sender in that configuration. That sender is part of the aux fan circuit, so you might need to rig a switch to manually turn on the fans when the temp rises.

This is what the sensor should look like, which definitely looks like a standard NPT thread.




Good luck

[barry123400]

Make or find an adapter to get the original temperature sensor mounted. That is the easiest route in my mind.

[tangofox007]

Originally Posted by mach4

The thermostat housing looks like a good candidate as it appears that there is enough material there to drill and tap to 3/8NPT. You can probably find a compatible sender in that configuration. That sender is part of the aux fan circuit...

Not on an '84 300SD.

[mach4]

Originally Posted by tangofox007

Not on an '84 300SD.

Hmmm... is the '84 different from the '85 (Cali)?

I just spent a bunch of time trying to track down the various senders as part of my conversion and this post shows what I came up with as far as the temp senders and switches.

380SL Diesel Conversion Project

Am I wrong?

If so, sorry about putting out bad info...

[marybeth]

Thanks for the feedback. Putting a Durango Temp sender was my first thought also. However finding an adapter for the "hole" in the MB that housed the orginal MB temp sender is a challenge.

Anyone know what size hole and thread the MB original 1984 MB temp sender is? If I know that I can have a shop fabricrate some type of adapter.

I spent some time at a hardware store that also specializes in Boat parts (We are near a large port here in South Florida)-they had a massive selection of all types of fittings -foreign and domestic. Butt nothing that fit the MB Temp sender.

Any thoughts would be appreciated.

Thanks!