I just recently bought the barth and on the ride home i noticed the original temp gauge on the dash wasnt working. I finally had time to pulled the cover off the motor & it looks like the sending unit is on drivers side of motor about midway , below valve covers. Can someone confirm this is where its at ? Is there a way to test the sending unit or gauge ? Or would it be better to just purchase a new gauge and sending unit that tells me in degree what the motor temp is ? the original gauge doesnt show degree just C / H . thanks , Bob

quote:

Originally posted by crouch38:
Is there a way to test the sending unit or gauge ?

Most one wire sending units is nothing more than a resistance for ground. Once heat rises, it makes for a better ground connection. It's a variable ground connection that is dependent on heat to regulate the ground resistance.

To test, turn on key and then remove wire from the sending unit and see if the gauge goes to the coldest position -

With key still on, take this wire and ground it to a good ground source, like an alternator bracket or something metal that is not rusty. Gauge should now peg out to the hottest position.

If all of this holds true, replace that sending unit only as this is most likely the problem now. DO NOT OVERTIGHTEN when reinstalling or use additional sealing on the threads as this will distort the readings.

quote:

Originally posted by crouch38:
Or would it be better to just purchase a new gauge and sending unit that tells me in degree what the motor temp is ? the original gauge doesnt show degree just C / H .

That would be a personal choice issue... if you wish to see an actual temp reading then you would need to replace both the sending unit and the gauge.

Don't throw out the gauge... offer it in the swap meet area and if no one takes you up on it, toss it out then.

When I bought my Barth none of the factory gauges worked and the previous owner installed a cobbled assortment of aftermarket gauges to replace them. I went to my local NAPA store and bought new sending units by make and model. I installed the new sending units and cleaned the contacts on the back of the gauges to get them all working. I removed all the aftermarket mechanical gauges and have no problem with trusting the factory gauges.
To answer your question that should be the correct sender for the temp. It you ground the wire going to the sender the gauge should go to full hot.

The sender unit is in the middle of the side of the cylinder head on the 454. I couldn't get my old one out, access on the driver side is hindered by either steering or brake components, I don't recall which.

It was easy to get the plug out of the passenger side head, so I put my new sender unit there.

Happy Motoring,
Matt

I finally had time to check the gauge and sending unit . the sending unit was on the drivers side. the gauge registered like Bill and others said to test. so i replaced the sending unit. works as it should now. thanks , to ALL who helped me out. Bob