Fuel pump
Thread Starter
Racer
Joined: Mar 2004
Posts: 266
Likes: 0
From: Wellsboro PA
Fuel pump
My fuel pump has been pushing oil out of the weep holes. After reading all of the former threads on the subject, I ordered a rebuild kit from L. I. C. It is scheduled to arrive on Monday. In the mean time I decided to disassemble the pump to have it ready for the new kit. Incidentally, this is a fairly new #40083 replacement that has approximately 1,500 miles on it. The weep hole problem was noticed soon after it was installed along with the engine rebuild. the bottom half has no indication of internal oil at all. The diaphragm looks perfect with the exception of the topside oil. I believe that the problem is the top oil seal. I have tried to remove the diaphragm using the method described in the shop manual. With the top clamped inverted in the rubber jaws of my vise, I have used a screwdriver to raise the actuating lever as I depress the diaphragm and push away from the rocker arm. It ain't working! 
Can someone please tell me, or better yet show me, how to succeed?
Can someone please tell me, or better yet show me, how to succeed?
Safety Car
Joined: Mar 2001
Posts: 4,359
Likes: 116
From: AUSTIN Tx
My fuel pump has been pushing oil out of the weep holes. After reading all of the former threads on the subject, I ordered a rebuild kit from L. I. C. It is scheduled to arrive on Monday. In the mean time I decided to disassemble the pump to have it ready for the new kit. Incidentally, this is a fairly new #40083 replacement that has approximately 1,500 miles on it. The weep hole problem was noticed soon after it was installed along with the engine rebuild. the bottom half has no indication of internal oil at all. The diaphragm looks perfect with the exception of the topside oil. I believe that the problem is the top oil seal. I have tried to remove the diaphragm using the method described in the shop manual. With the top clamped inverted in the rubber jaws of my vise, I have used a screwdriver to raise the actuating lever as I depress the diaphragm and push away from the rocker arm. It ain't working!
Can someone please tell me, or better yet show me, how to succeed?
Can someone please tell me, or better yet show me, how to succeed?
I have never had a problem removing one. There is a slot on the diaphragm shaft that the hook in the end of the arm engages. Just push down on the diaphragm, and angle it so the shaft goes away from the mounting flange of the pump, and it should come off. You can also try twisting a little as you work it. The hook is not very deep, and it should not take much pushing to get it off. The key is to angle the diaphragm so that the shaft moves away from the hook.
Regards, John McGraw
Safety Car
Joined: May 2003
Posts: 4,797
Likes: 239
From: Ocean Township NJ
My fuel pump has been pushing oil out of the weep holes. After reading all of the former threads on the subject, I ordered a rebuild kit from L. I. C. It is scheduled to arrive on Monday. In the mean time I decided to disassemble the pump to have it ready for the new kit. Incidentally, this is a fairly new #40083 replacement that has approximately 1,500 miles on it. The weep hole problem was noticed soon after it was installed along with the engine rebuild. the bottom half has no indication of internal oil at all. The diaphragm looks perfect with the exception of the topside oil. I believe that the problem is the top oil seal. I have tried to remove the diaphragm using the method described in the shop manual. With the top clamped inverted in the rubber jaws of my vise, I have used a screwdriver to raise the actuating lever as I depress the diaphragm and push away from the rocker arm. It ain't working!
Can someone please tell me, or better yet show me, how to succeed?
Can someone please tell me, or better yet show me, how to succeed?
Thread Starter
Racer
Joined: Mar 2004
Posts: 266
Likes: 0
From: Wellsboro PA
Whoops! Just checked the service manual and lever appears not to block access to the seal.
Last edited by Thomas66; Sep 7, 2012 at 11:48 PM.
Safety Car
Joined: Mar 2001
Posts: 4,359
Likes: 116
From: AUSTIN Tx
I found your article, helps a lot. I was trying to remove the diaphragm with out removing the pivot pin. It appears that even if I were successful, the lever would obstruct seating of the oil seal. The pin on this replacement pump has been swagged. That presents a challenge. The dog is getting a little foot shy.
Whoops! Just checked the service manual and lever appears not to block access to the seal.
Whoops! Just checked the service manual and lever appears not to block access to the seal.
Regards, John McGraw
Thread Starter
Racer
Joined: Mar 2004
Posts: 266
Likes: 0
From: Wellsboro PA
I am still working on getting the diaphragm out. This has got to be the most frustrating thing that I have faced since I have had this car. Like many, if not most, this covette has no reason to complain. She has had a major make over. But I have hit the wall with this pump diaphragm. Will removing the pivot pin and then pulling the lever be the way to go now?
The .44 may be the next tool in the box.
The .44 may be the next tool in the box.
Race Director
Joined: Mar 2009
Posts: 19,777
Likes: 4,592
From: Canada's capital
2020 Corvette of the Year Finalist (appearance mods)
C1 of Year Finalist (appearance mods) 2019
I am still working on getting the diaphragm out. This has got to be the most frustrating thing that I have faced since I have had this car. Like many, if not most, this covette has no reason to complain. She has had a major make over. But I have hit the wall with this pump diaphragm. Will removing the pivot pin and then pulling the lever be the way to go now?
The .44 may be the next tool in the box.
The .44 may be the next tool in the box.
Thread Starter
Racer
Joined: Mar 2004
Posts: 266
Likes: 0
From: Wellsboro PA
Could it be that this is a replacement pump? Possibly with a deeper hook groove on the lever? I have pushed, tilted, and twisted the diaphragm. I have been able to visualize what I can not see, but it will not release. As of this afternoon this will be my back-up pump. I ordered a new pump. I hope the oil seal is better in this one.
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