1937 Lasalle gas tank sender unit

[J. Bice CLC #24805]

Hi guys,

I've seen a few posts on this topic, but none that conclusively have ruled the best option for repair or replacement. The original unit I have always reads wrong; it has a good ground but when I think it might be working properly, it screws up again. The two replacements I was looking at were the one from Bob's Automobilia and the one always on ebay. Does anyone have experience with either of these units?

http://bobsautomobilia.com/shop/fuel-system/gas-tank-sender-1936-56-fs-368.html

http://www.ebay.com/itm/Cadillac-fuel-tank-sending-unit-1937-1949-Stainless-Steel-0-30-ohm-/350506129900

[Steve Passmore]

The one on ebay will NOT fit your car. In 37 all GM senders incorporated the pickup tube for the fuel and those do not have it. Looks like Bobs is an after-market with the rheostat half way down the pickup tube instead of on top like yours but should work.

Before you go buying have you removed yours yet?  Last year I repaired three of my cars sender units which had stopped working over the past two years and I presumed they were finished. When I removed them from the tank they seemed OK and connected up would actually operate the gauge but would not work in the tank, then I realized how heavy they seemed, they were sinking to the bottom. Something maybe to do with the fuel additives I don't know but these cork floats had the shellac eroded off allowing the cork to become saturated with gas. I converted all three to modern plastic floats and they all work great. We have recently in the last few years been having Ethanol in our petrol so who knows? but I have never seen this before.

[J. Bice CLC #24805]

Thanks Steve. I know Bob's sells replacement cork and brass floats; what kind of plastic float did you use?  Think I have the same problem you did. I tested it a year ago and it was fine out of the tank. Now it has gradually gotten worse.

[Steve Passmore]

They were just floats from modern senders found at flea markets.

[B Readling CLC#25871]

You might talk with John Wolf,Co. John did my gauge cluster and sending unit. Not cheap but well done.

[J. Bice CLC #24805]

You might talk with John Wolf,Co. John did my gauge cluster and sending unit. Not cheap but well done.

I did - he quoted $130 for restoration of the sender over the phone. I'm willing to think it is just the float, but I'm considering the middle road with the Bob's Automobilia unit for $75. It has new stainless components with a brass float.  I am sending out my speedo to John Wolf though for a good cleaning and mild restoration.

[harvey b]

Can you let us know how the bobs sending unit works out,i have the same problem with my 37,and am lookiing for a replacement too,would like to know if this works before i buy one. harvey

[J. Bice CLC #24805]

Can you let us know how the bobs sending unit works out,i have the same problem with my 37,and am lookiing for a replacement too,would like to know if this works before i buy one. harvey

Harvey,

Still working on it. The old unit was pretty bad - I had it working fine about 5 years ago, but that time in modern gas completely froze the sender mechanism. I can't get it to move at all. And as we figured earlier, the cork was rough too. I have the new unit from Bob's. So far, I've had to do some modifications, including bending the float rod down for proper clearance at the top end. Also the five screw holes did not match up exactly and I had to enlarge two of them. It all tests fine now so it's just getting the time to put it back up. I'll probably add a direct ground to the frame while I'm at it.  I'll try to post some pictures later.