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B Body Sending Unit #2865182 12/27/20 10:53 AM 12/27/20 10:53 AM
Joined: Nov 2004 Posts: 144 T Tony440 OP member
Tony440 OP member T Joined: Nov 2004 Posts: 144	Hello, can a fuel sending unit for a 67 B body be removed from the gas tank without removing the tank? I have a 67 Coronet R/T that isn't getting fuel to the pump. I replaced the pump and filter. I suspect a blockage in either the line or the sending unit. Thanks.

Re: B Body Sending Unit [Re: Tony440] #2865201 12/27/20 11:49 AM 12/27/20 11:49 AM
Joined: Jan 2003 Posts: 10,702 North Dakota 6PakBee I Live Here
6PakBee I Live Here Joined: Jan 2003 Posts: 10,702 North Dakota	It's been a long time since I did it but I replaced the sending unit on a '67 Belvedere years ago. IIRC, I did not have to drop the tank. If you can get the car on a hoist, do it. Makes the job soooo much easier. "We live in a time when intelligent people are being silenced so that stupid people won't be offended".

Re: B Body Sending Unit [Re: 6PakBee] #2865222 12/27/20 12:42 PM 12/27/20 12:42 PM
Joined: Nov 2004 Posts: 144 T Tony440 OP member
Tony440 OP member T Joined: Nov 2004 Posts: 144	Thanks so much for your reply.

Re: B Body Sending Unit [Re: Tony440] #2865258 12/27/20 02:06 PM 12/27/20 02:06 PM
Joined: Jan 2003 Posts: 15,291 Omaha Ne T TJP I Live Here
TJP I Live Here T Joined: Jan 2003 Posts: 15,291 Omaha Ne	In over 50 years I have never seen a blocked line inside a tank. I would suggest putting a vacuum gauge on the pump to make sure it's pulling and then move the gauge to the hose at the sending unit and repeat the test. If you have the same vacuum reading then you have eliminated everything to the tank You didn't say what motor, type of pump etc. you're dealing with so I'm assuming it's a mechanical pump. A loose or rotted hose or a pinhole in the line (rusty) will wreak havoc. If it happens to be a big block it could also be the fuel pump pushrod. getting the car up with the rear end hanging will give you much better access to the sending unit if you do wind up going there. keep us posted www.tandmautomotive-omaha.com

Re: B Body Sending Unit [Re: TJP] #2865278 12/27/20 02:37 PM 12/27/20 02:37 PM
Joined: Jan 2003 Posts: 10,702 North Dakota 6PakBee I Live Here
6PakBee I Live Here Joined: Jan 2003 Posts: 10,702 North Dakota	Originally Posted by TJP In over 50 years I have never seen a blocked line inside a tank. I would suggest putting a vacuum gauge on the pump to make sure it's pulling and then move the gauge to the hose at the sending unit and repeat the test. If you have the same vacuum reading then you have eliminated everything to the tank You didn't say what motor, type of pump etc. you're dealing with so I'm assuming it's a mechanical pump. A loose or rotted hose or a pinhole in the line (rusty) will wreak havoc. If it happens to be a big block it could also be the fuel pump pushrod. getting the car up with the rear end hanging will give you much better access to the sending unit if you do wind up going there. keep us posted Unfortunately, the Belvedere one I replaced was due to the 'sock' filter in the tank being completely and totally plugged with crud. So yes, it does happen. As a note, if you resort to blocking or jackstands, keep the car level. If you have the rear end elevated and there is gas in the tank, there is a good possibility of it coming out when you remove the sender. DAMHIK. I know some will talk about siphoning the gas out but I have never had good luck doing that on a '67 B-body tank. Just be careful, we don't want to play Buddhist monk here. "We live in a time when intelligent people are being silenced so that stupid people won't be offended".

Re: B Body Sending Unit [Re: 6PakBee] #2865290 12/27/20 03:11 PM 12/27/20 03:11 PM
Joined: Nov 2004 Posts: 144 T Tony440 OP member
Tony440 OP member T Joined: Nov 2004 Posts: 144	Thanks everyone for the replies. The motor is a 440, the pump is a stock replacement mechanical unit. I'm going to check for vacuum at the pump as suggested. The sending unit doesn't have a sock on it but is over 20 years old, as is the rubber line from the pump to the steel line, and rubber line from the sending unit to steel line.

Re: B Body Sending Unit [Re: TJP] #2865307 12/27/20 03:55 PM 12/27/20 03:55 PM
Joined: May 2005 Posts: 4,705 Florida BDW master
BDW master Joined: May 2005 Posts: 4,705 Florida	Originally Posted by TJP A loose or rotted hose or a pinhole in the line (rusty) will wreak havoc. keep us posted This happened to me, rubber line from hard line to fuel pump had small split/hole that took me a while to figure out. Last edited by BDW; 12/27/20 03:55 PM.

Re: B Body Sending Unit [Re: BDW] #2865317 12/27/20 04:08 PM 12/27/20 04:08 PM
Joined: Jan 2003 Posts: 18,407 UPPER MICHIGAN, MARQUETTE COUN... N NITROUSN I Live Here
NITROUSN I Live Here N Joined: Jan 2003 Posts: 18,407 UPPER MICHIGAN, MARQUETTE COUN...	Quote The sending unit doesn't have a sock on it but is over 20 years old I hope you have a filter before the pump. Myself I always keep the sock on the sending unit.

Re: B Body Sending Unit [Re: NITROUSN] #2865360 12/27/20 05:44 PM 12/27/20 05:44 PM
Joined: Nov 2004 Posts: 144 T Tony440 OP member
Tony440 OP member T Joined: Nov 2004 Posts: 144	I don't have filter before the pump. It's between the pump and carbs. The filter I pulled out was a plastic one and it had what looked like black pieces of what may have been rubber hose. Maybe that's an indication of a hose starting to disintegrate.

Re: B Body Sending Unit [Re: Tony440] #2865400 12/27/20 07:26 PM 12/27/20 07:26 PM
Joined: Jan 2003 Posts: 18,407 UPPER MICHIGAN, MARQUETTE COUN... N NITROUSN I Live Here
NITROUSN I Live Here N Joined: Jan 2003 Posts: 18,407 UPPER MICHIGAN, MARQUETTE COUN...	You need to protect the pump. No tank or filter on the inlet side of the pump is a disaster waiting to happen. Anything that gets sucked off the tank bottom gets into the pumps check valves. Result is failed pump. Plus you can suck larger items that could plug the line.

Re: B Body Sending Unit [Re: NITROUSN] #2865446 12/27/20 09:00 PM 12/27/20 09:00 PM
Joined: Jan 2003 Posts: 20,740 A collage of whims topside Too Many Posts
topside Too Many Posts Joined: Jan 2003 Posts: 20,740 A collage of whims	Shine a flashlight into the tank and look for something like a shop rag. A buddy once did that to one of my cars as a prank. Very effective at shutting off fuel supply until engine dies, starts up, dies again when rag is sucked back around pickup. A hose that splits inside also works like a one-way valve, and never in the "right" way.

Re: B Body Sending Unit [Re: NITROUSN] #2865623 12/28/20 10:53 AM 12/28/20 10:53 AM
Joined: Nov 2004 Posts: 144 T Tony440 OP member
Tony440 OP member T Joined: Nov 2004 Posts: 144	Thanks again for everyone's input since the rubber line from the steel line to the pump and the line from the sending unit to the steel line is over 20 years, old I'm going to replace them as a start. I was always told that you should not put one of the paper type filters before the pump, because it will decrease fuel pressure to the pump. That's why the factory put the fuel filter between the pump and carbs. Is this true?

Re: B Body Sending Unit [Re: Tony440] #2865628 12/28/20 11:13 AM 12/28/20 11:13 AM
Joined: May 2019 Posts: 6,221 nowhere S Sniper master
Sniper master S Joined: May 2019 Posts: 6,221 nowhere	Originally Posted by Tony440 Thanks again for everyone's input since the rubber line from the steel line to the pump and the line from the sending unit to the steel line is over 20 years, old I'm going to replace them as a start. I was always told that you should not put one of the paper type filters before the pump, because it will decrease fuel pressure to the pump. That's why the factory put the fuel filter between the pump and carbs. Is this true? Is it true? Yes and no. It doesn't "decrease fuel pressure to the pump" as there is no pressure there, but rather a vacuum. What it does is make it harder for the pump to draw from the tank and the dirtier the filter gets the more it affects the draw. Fuel pumps are better at pushing than pulling so you don't want a restriction on the pull side The sock on the pickup in the tank is fairly coarse and is designed to keep the big chunks out of the pump. The filter between the pump and carb is designed to catch much smaller stuff that normally does not affect the pump but will affect the carb.

Re: B Body Sending Unit [Re: Sniper] #2865644 12/28/20 12:05 PM 12/28/20 12:05 PM
Joined: Nov 2004 Posts: 144 T Tony440 OP member
Tony440 OP member T Joined: Nov 2004 Posts: 144	That's what I thought. I guess I should put a sock on the sending unit. Thanks for explaining this about the vacuum draw.

Re: B Body Sending Unit [Re: Sniper] #2865657 12/28/20 12:51 PM 12/28/20 12:51 PM
Joined: Jan 2003 Posts: 15,291 Omaha Ne T TJP I Live Here
TJP I Live Here T Joined: Jan 2003 Posts: 15,291 Omaha Ne	Originally Posted by Sniper Is it true? Yes and no. It doesn't "decrease fuel pressure to the pump" as there is no pressure there, but rather a vacuum. What it does is make it harder for the pump to draw from the tank and the dirtier the filter gets the more it affects the draw. Fuel pumps are better at pushing than pulling so you don't want a restriction on the pull side The sock on the pickup in the tank is fairly coarse and is designed to keep the big chunks out of the pump. The filter between the pump and carb is designed to catch much smaller stuff that normally does not affect the pump but will affect the carb. But will clarify, A paper filer before the pump may restrict the flow a small amount and technically require a bit more vacuum (which is negative pressure) But it is unlikely you would be able to measure the difference unless you were using laboratory grade instruments. But as stated above if the filter starts getting dirty, the vacuum the pump produces will remain the same, but the flow will be reduced. The dirtier it becomes the lower the flow to the point it is completely blocked. If you look at most fuel injection aftermarket systems they require a 10 micron filter Before the pump and a 3 micron after www.tandmautomotive-omaha.com

Re: B Body Sending Unit [Re: TJP] #2865661 12/28/20 01:06 PM 12/28/20 01:06 PM
Joined: May 2019 Posts: 6,221 nowhere S Sniper master
Sniper master S Joined: May 2019 Posts: 6,221 nowhere	Originally Posted by TJP If you look at most fuel injection aftermarket systems they require a 10 micron filter Before the pump and a 3 micron after Just to point out that most FI systems have the pump in the tank with the filter right at the pump's input so it's not trying to suck thru 10+ feet of fuel line either. I imagine that helps.

Re: B Body Sending Unit [Re: TJP] #2865707 12/28/20 02:27 PM 12/28/20 02:27 PM
Joined: Sep 2003 Posts: 19,320 north of coder moparx "Butt Crack Bob"
moparx "Butt Crack Bob" Joined: Sep 2003 Posts: 19,320 north of coder	iagree But will clarify, A paper filer before the pump may restrict the flow a small amount and technically require a bit more vacuum (which is negative pressure) no such thing as "negative" pressure. it could be described as "negative" but it is truly "opposite" or "absence" of pressure........... just yankin' yer chain ! my one close buddy and i argue this point every chance we get just because.

Re: B Body Sending Unit [Re: Tony440] #2867918 01/02/21 01:54 AM 01/02/21 01:54 AM
Joined: Jan 2003 Posts: 3,482 Cold Spring, NY 1970GTX master
1970GTX master Joined: Jan 2003 Posts: 3,482 Cold Spring, NY	Originally Posted by Tony440 Hello, can a fuel sending unit for a 67 B body be removed from the gas tank without removing the tank? Yes, Put the rear frames on jack stands. You will have enough room to swivel the sending unit out. Reuse the lock ring and gasket if it is good. The new ones do not fit and seal well. Make your life easy and buy the correct spanner wrench to remove the lock ring. https://www.manciniracing.com/moseunloriwr.html Replace the sock and ground clip. https://www.manciniracing.com/moseungrst33.html https://www.manciniracing.com/3pifimlior1.html

Re: B Body Sending Unit [Re: 1970GTX] #2867958 01/02/21 09:33 AM 01/02/21 09:33 AM
Joined: Jan 2003 Posts: 10,702 North Dakota 6PakBee I Live Here
6PakBee I Live Here Joined: Jan 2003 Posts: 10,702 North Dakota	I hate to disagree but I'd clean up your old ground strap and reuse it. I've never found a reproduction strap from anyone that works. They don't seem to be made from spring steel like the originals and once you force them over the fuel lines, they are loose. If you insist on buying a new one, don't throw the old one away until you have tried to install the replacement. "We live in a time when intelligent people are being silenced so that stupid people won't be offended".

Re: B Body Sending Unit [Re: 6PakBee] #2868018 01/02/21 11:16 AM 01/02/21 11:16 AM
Joined: Aug 2009 Posts: 1,317 Ohio J jlatessa pro stock
jlatessa pro stock J Joined: Aug 2009 Posts: 1,317 Ohio	Agree, Bee, have been through a few repos, No spring to the clamps. On one car I soldered a lead to make a reliable connection. Joe

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