News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

1981 Coupe Deville Fuel tank sending unit

Started by joelific, April 12, 2019, 08:48:40 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

joelific

Hey all. I'm trying to find the fuel tank sending unit for my '81 Coupe, with the 6.0 368. Tried everywhere on line and they're all sold out. Does anyone have a connection for one? Have one laying around that you'd like to sell? Please let me know. Thanks. Joe

TJ Hopland

What is wrong with yours?   Do you have any clues yet what is apparently unique about that model and year?   I would have thought it was the same for all the RWD cars 81-85.  I do remember reading that they changed to a different style of electrical connectors for 82 so maybe that is the difference?  And if you changed the connector maybe the later one would work?
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

bcroe

81 was the one year 8/6/4 engine, using a direct tank pump to
low pressure TB injectors.  Different from the 70s 2 pump system
and likely different from the 4.1 system in 82.  But I would expect
the main difference would be the type pump used, not very critical
for a smaller engine with low fuel pressure.  I have changed pumps,
done repairs on the rest. 
Bruce Roe

joelific

Well the fuel pump in my Coupe is no good, and since I'm changing out the pump, I might as well as change out the sending unit as well, as I've noticed the fuel gauge readout fluctuates back and forth, & isn't accurate. I was under the impression that since they ('80-'85 RWD) had the same size gas tank (24 gallon), that their sending units would be the same, & it would be easy for me to find a unit. Am I wrong???

Eric DeVirgilis CLC# 8621

Need someone with a MPL (Master Parts List) to determine compatibility.

As Bruce mentions, there is a strong possibility the 1981 fuel pump/sending unit unique to the V8-6-4 engine and not interchangeable with the HT4100 engine that appeared the following year.

Limousines however were equipped with the V8-6-4 from 1981 - 1984 so there's every possibility the pump & SU from one of those cars would also interchange- in the remote chance that one became available.   
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

joelific

#5
I never thought of that Eric. I'll look into the Limos from 81-84 and see if I can pull up a sending unit for that.
Just wish I could find someone with a MPL to show me exact compatibility with my sending unit. Just very frustrating.

UPDATE: found a sending unit that fits the commercial chassis (limousine) with the 368 6.0
They have the same size gas tank (24 gallon) apparently. Praying this solves my search for the sending unit. Thanks for the tip, Eric...

http://bit.do/sendingunit

Eric DeVirgilis CLC# 8621

Don't get that one! The Commercial Chassis had the 6.0 Liter carburetor engine. It is not the V8-6-4 fuel injected 6.0! Must be from a LIMOUSINE only 81-84.

My apologies for not making that clear before.

A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

joelific

#7
Eric, the one I got is for the FI commercial chassis. Didn't buy this one listed above, after all. Got the 1 below instead. It's made for the '82 Formal Limousine, with the 6.0 FI 8-6-4 engine.

https://www.amazon.com/gp/product/B000C7S224/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1

Eric DeVirgilis CLC# 8621

Quote from: joelific on April 19, 2019, 09:21:40 AM
Eric, the one I got is for the FI commercial chassis. Didn't buy this one listed above, after all. Got the 1 below instead. It's made for the '82 Formal Limousine, with the 6.0 FI 8-6-4 engine.

https://www.amazon.com/gp/product/B000C7S224/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1

Just be aware that the Limousine and a Commercial Chassis are not the same thing.

No commercial chassis left the factory with the V8-6-4 from 1981-1984. The commercial chassis was a bare bones unfinished chassis which was sent to a coachbuilder for the body which the car would ultimately receive- usually becoming hearses, flower cars and such. These cars got the 6.0 liter with 4 bbl carburetor which did not have an in-tank fuel pump.

A regular production Limousine left the factory as a finished car and is not a Commercial Chassis. V8-6-4 was the only engine used in either Limousine model (base or Formal). 

The unit you have shown appears to be a sending unit only. The in-tank units I'm most familiar with most modern FI vehicles are integral fuel pump & sending unit.

I cannot say whether the sending unit and fuel pump were two independent assemblies in cars equipped with the V8-6-4 engine.
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

joelific

#9
Well when I ordered this on Amazon, what I did was default my car as a "1982 Cadillac Fleetwood Formal", which I know is the Limousine & NOT the commercial chassis. Sorry if I worded my previous post incorrectly. As far as I have been made known, the fuel pump & sending unit are 2 separate pieces, not a complete solid unit, with the 8-6-4 FI 368. I've already purchased the fuel pump seperately.




Quote from: Eric DeVirgilis CLC# 8621 on April 19, 2019, 12:47:55 PM
Just be aware that the Limousine and a Commercial Chassis are not the same thing.

No commercial chassis left the factory with the V8-6-4 from 1981-1984. The commercial chassis was a bare bones unfinished chassis which was sent to a coachbuilder for the body which the car would ultimately receive- usually becoming hearses, flower cars and such. These cars got the 6.0 liter with 4 bbl carburetor which did not have an in-tank fuel pump.

A regular production Limousine left the factory as a finished car and is not a Commercial Chassis. V8-6-4 was the only engine used in either Limousine model (base or Formal). 

The unit you have shown appears to be a sending unit only. The in-tank units I'm most familiar with most modern FI vehicles are integral fuel pump & sending unit.

I cannot say whether the sending unit and fuel pump were two independent assemblies in cars equipped with the V8-6-4 engine.

Eric DeVirgilis CLC# 8621

Quote from: joelific on April 19, 2019, 03:56:31 PM
Well when I ordered this on Amazon, what I did was default my car as a "1982 Cadillac Fleetwood Formal", which I know is the Limousine & NOT the commercial chassis. Sorry if I worded my previous post incorrectly. As far as I have been made known, the fuel pump & sending unit are 2 separate pieces, not a complete solid unit, with the 8-6-4 FI 368. I've already purchased the fuel pump.

Sounds like you're okay then. Best of luck with the repairs.
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

joelific

Quote from: Eric DeVirgilis CLC# 8621 on April 19, 2019, 04:03:23 PM
Sounds like you're okay then. Best of luck with the repairs.

I truly appreciate your input, Eric. If it weren't for you, I'd STILL be scrambling for a sending unit for my Coupe. Thanks so much!

Eric DeVirgilis CLC# 8621

Glad if the info proves helpful. Looking forward to hearing how it works out.
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

joelific

Quote from: Eric DeVirgilis CLC# 8621 on April 19, 2019, 04:38:23 PM
Glad if the info proves helpful. Looking forward to hearing how it works out.

Just an update. The sending unit from Amazon worked out perfectly. Thank you again for your advice. Much appreciated.

Eric DeVirgilis CLC# 8621

A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute