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MrBulldops
11-11-2017, 02:45 PM
1960 Lark 6

I replaced the gauge and sender a couple months ago and everything worked fine. Today though, my gauge would read dead cold even after the engine was warmed up, then randomly work fine or climb nearly halfway and go cold again, or seem to read normally for a few minutes, then jump to 3/4, and go cold again. I'm assuming it's the sender; it's a reproduction from Studebaker Parts, but I'm gonna assume it's probably a cheapo manufacture from Mexico or China.

I ordered a replacement sender from AutoZone that should be here in a few days, but I'm wondering if anyone else has had this problem and discovered a different cause.

I already tested the gauge, attaching the sending wire to the negative terminal of my battery and the gauge responds normally. I also made sure that the wire connects solidly to the sender and that it's free of corrosion. Hookups on the gauge are correct and solid also. As I said, it's worked fine for the last couple of months.

Backup plan is to replace the gauge with an under dash unit, but if that's the way I go, of like to blank that gauge in the dash. Did Studebaker make a delete plate that'll fit that hole? The gauge cluster is less that 4" wide, and everything I've found seems more like 4-1/2".

gordr
11-11-2017, 04:36 PM
May well be a bad sender. If the wire has one of those "L"-shaped push-om terminals, sometimes the metal in them loses its grip, and a flaky connection results. Last I heard, there were plenty of NOS gauge units still available.

A '63 - '66 factory clock would fit the hole left by the gauge cluster; perfectly.

MrBulldops
11-11-2017, 05:44 PM
May well be a bad sender. If the wire has one of those "L"-shaped push-om terminals, sometimes the metal in them loses its grip, and a flaky connection results. Last I heard, there were plenty of NOS gauge units still available.

A '63 - '66 factory clock would fit the hole left by the gauge cluster; perfectly.

Groovy. I'll keep that in mind. I'll double check those connectors, but I seem to recall bending them slightly when I replaced the gauges. I suppose I could just replace them with spades if it continues after I replace the sending unit.

StudeRich
11-11-2017, 08:44 PM
This sounds exactly like a Loose Terminal on the Temp. Sender, which is why it is intermittent, a VERY common ailment.

MrBulldops
11-12-2017, 08:14 AM
This sounds exactly like a Loose Terminal on the Temp. Sender, which is why it is intermittent, a VERY common ailment.

The terminal does spin in the housing. Doesn't feel like it can be tightened down though.

altair
11-12-2017, 01:05 PM
Just a thought, did you screw the sender in with Teflon tape, maybe the ground is interrupted?

MrBulldops
11-12-2017, 03:55 PM
Just a thought, did you screw the sender in with Teflon tape, maybe the ground is interrupted?

No tape. Avoided it for just that reason. Also, it's working fine today. I replaced my voltage regulator last night, among other things. Might be a coincidence, or it could stop working again tomorrow. Guess we'll have to wait and see

kxet
11-12-2017, 06:43 PM
Engine have good ground to body?

MrBulldops
11-12-2017, 09:42 PM
Engine have good ground to body?

It should. Rebuilt clutch and replaced the motor mounts, front and back, recently and did as much degreasing and cleanup as possible.

1954khardtop
11-13-2017, 08:29 AM
Make sure you have a ground strap or wire from the engine to the firewall. The motor mounts are not good conductors. I run a ground wire from the top bolt to the bottom bolt on one of the motor mounts.

MrBulldops
11-13-2017, 12:15 PM
Make sure you have a ground strap or wire from the engine to the firewall. The motor mounts are not good conductors. I run a ground wire from the top bolt to the bottom bolt on one of the motor mounts.

That's a good idea. Plenty of room the passenger side front door that.

MrBulldops
11-13-2017, 11:31 PM
There's actually supposed to be a grounding wire from the engine to a point on the frame just below the passenger side front motor mount. Mine was missing; a bolt and bare connector were there, but no wire. I ran a 6 gauge 12" switch cable from that point to the bracket above it. Ohm readings before, taken from a head bolt to the hood latch would fluctuate between 1 and 15 ohms. Now it reads 0.1 to 0.5

MrBulldops
11-15-2017, 10:33 PM
Been a few days and now it seems to be working fine. Grounding the engine, along with some other electrical components I replaced for a seemingly unrelated issue seems to have corrected it. Still, I bought a spare sender just in case

TWChamp
11-16-2017, 07:37 AM
Since you are having starting and running problems also, I think you have an electrical connection problem. When I bought my 50 Champion a few years ago, the terminal was loose on the back of the ignition switch. This loose connection caused heat, which corroded the threads and made the nut hard to turn. I used Kroil and finally got the nut to turn tight, and that took care of the problems.

MrBulldops
11-16-2017, 11:21 AM
Since you are having starting and running problems also, I think you have an electrical connection problem. When I bought my 50 Champion a few years ago, the terminal was loose on the back of the ignition switch. This loose connection caused heat, which corroded the threads and made the nut hard to turn. I used Kroil and finally got the nut to turn tight, and that took care of the problems.

I'll have to look into that. I may just replace the switch altogether.