Question on fuel supply?
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Question on fuel supply?
My 77 started to have "gas withdrawls" LOL the other day when I took her out. At cruising speeds below 60 she is fine. But when you hit the gas she'll start to pull then die - starve for gas. So I figured it was the fuel filter (in the carb). I replaced it with a new one. I just took her out again now, and as soon as I hit the gas harder then normal she starve's. I noticed there was a "oil puddle" very small in the garage. When I went to wipe it up it was more watery then oil. I looked underneath and see the bottom of the fuel pump is wet, and so is everything behind it. Can a fuel pump leak? I thought it was a sealed unit. I will be replacing this next. Should I just get the reg. one or are there any "special" pumps I should look for since I'll be replacing it. Thanks......
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Thank you. I did not realize they had a weep hole like a water pump. I won't be running the car anymore, since you say it's possible for it to leak into the crankcase. I hope nothing went in it. Do you think I should do an oil change.? I just did one a couple weeks ago. I'd hate to do it again. But on the other hand I'd hate to have it contaminated...
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
When replacing the pump, would you recommend placing a filter in-line between the pump and carb.? Threaded of course. Or is the one in the carb. sufficient.?
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Your welcome. Here's a thread that talk about fuel pump changes and how to hold the rod up.
http://forums.corvetteforum.com/c3-g...questions.html
Some find it easier to go under the fender to get at the bolts. Use a battery operated light when around fuel. Good Luck
http://forums.corvetteforum.com/c3-g...questions.html
Some find it easier to go under the fender to get at the bolts. Use a battery operated light when around fuel. Good Luck
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Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Your welcome. Here's a thread that talk about fuel pump changes and how to hold the rod up.
http://forums.corvetteforum.com/c3-g...questions.html
Some find it easier to go under the fender to get at the bolts. Use a battery operated light when around fuel. Good Luck
http://forums.corvetteforum.com/c3-g...questions.html
Some find it easier to go under the fender to get at the bolts. Use a battery operated light when around fuel. Good Luck
Safety Car
Joined: Apr 2008
Posts: 3,908
Likes: 10
From: Charleston SC
Actually...my car is having almost the exact same problem..!
I can cruise all day long at 65...and almost at 70. Anything above that and within minutes, the car starts to sputter and jerk..when I back down to 65-70 it is fine.
When I accelerate, I can get up to 90 or so, but as soon as I let off the gas, the car is dead..
I also had a lot of wetness down there. Replaced the hoses and fuel pump (went back to an ACdelco with 3 lines) and still had the problem and wetness. Then I found that the coolant hose that goes to the firewall (heater?) was cracked bad at the base of the manfold. It had been spewing coolant.
Fixed it...still have the same problem though. But no more leak?
Needless to say, I am subscribed to this thread..
I can cruise all day long at 65...and almost at 70. Anything above that and within minutes, the car starts to sputter and jerk..when I back down to 65-70 it is fine.
When I accelerate, I can get up to 90 or so, but as soon as I let off the gas, the car is dead..
I also had a lot of wetness down there. Replaced the hoses and fuel pump (went back to an ACdelco with 3 lines) and still had the problem and wetness. Then I found that the coolant hose that goes to the firewall (heater?) was cracked bad at the base of the manfold. It had been spewing coolant.
Fixed it...still have the same problem though. But no more leak?
Needless to say, I am subscribed to this thread..
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Actually...my car is having almost the exact same problem..!
I can cruise all day long at 65...and almost at 70. Anything above that and within minutes, the car starts to sputter and jerk..when I back down to 65-70 it is fine.
When I accelerate, I can get up to 90 or so, but as soon as I let off the gas, the car is dead..
I also had a lot of wetness down there. Replaced the hoses and fuel pump (went back to an ACdelco with 3 lines) and still had the problem and wetness. Then I found that the coolant hose that goes to the firewall (heater?) was cracked bad at the base of the manfold. It had been spewing coolant.
Fixed it...still have the same problem though. But no more leak?
Needless to say, I am subscribed to this thread..
I can cruise all day long at 65...and almost at 70. Anything above that and within minutes, the car starts to sputter and jerk..when I back down to 65-70 it is fine.
When I accelerate, I can get up to 90 or so, but as soon as I let off the gas, the car is dead..
I also had a lot of wetness down there. Replaced the hoses and fuel pump (went back to an ACdelco with 3 lines) and still had the problem and wetness. Then I found that the coolant hose that goes to the firewall (heater?) was cracked bad at the base of the manfold. It had been spewing coolant.
Fixed it...still have the same problem though. But no more leak?
Needless to say, I am subscribed to this thread..
Safety Car
Joined: Apr 2008
Posts: 3,908
Likes: 10
From: Charleston SC
As for tuned...true, I did it myself, by the manual and other articles on the web. When I would raid or lower the fuel bowl floats, it wouldn't make a difference in regards to my problem. When I enriched or leaned it out, it also didn't seem to make a difference, though I didn't mess with those as much..
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Either way, it sounds as if your car is starving for fuel also. Either clogged line/filter? Or maybe even that piece you took out when you cleaned it. It may be possible a little oiece was left behind. I know EVERY time I work in my engine bay, I am always leaving somthing behind. Now I have learned to look THREE TIMES after I clean and put away everything. I also have all my tools in certain places, So I know if on'es missing. Good luck, keep us posted.
Safety Car
Joined: Apr 2008
Posts: 3,908
Likes: 10
From: Charleston SC
Either way, it sounds as if your car is starving for fuel also. Either clogged line/filter? Or maybe even that piece you took out when you cleaned it. It may be possible a little oiece was left behind. I know EVERY time I work in my engine bay, I am always leaving somthing behind. Now I have learned to look THREE TIMES after I clean and put away everything. I also have all my tools in certain places, So I know if on'es missing. Good luck, keep us posted.
For the first 10-15 minutes, I could have sworn the problem was solved. The car revved up to 90 or so before I let off and expected it to lose all power as usual...but it kept on running, and perfectly. Was able to cruise at any speed without hesitation, bucking, or stuttering.. But just as I got excited and comfortable...the car started showing the same symptoms and problems at any cruising speed above 70mph... banghead:
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Just replaced the carb with a simple Edelbrock I had on it a year ago..
For the first 10-15 minutes, I could have sworn the problem was solved. The car revved up to 90 or so before I let off and expected it to lose all power as usual...but it kept on running, and perfectly. Was able to cruise at any speed without hesitation, bucking, or stuttering.. But just as I got excited and comfortable...the car started showing the same symptoms and problems at any cruising speed above 70mph... banghead:
For the first 10-15 minutes, I could have sworn the problem was solved. The car revved up to 90 or so before I let off and expected it to lose all power as usual...but it kept on running, and perfectly. Was able to cruise at any speed without hesitation, bucking, or stuttering.. But just as I got excited and comfortable...the car started showing the same symptoms and problems at any cruising speed above 70mph... banghead:
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Well today I took the bad pump off. I cleaned up the exhaust manifold since I had it off again. I also wire wheeled the solid gas line from pump to carb. Then clear-coated it. As you can see in the pic's I used the trick - useing the longer bolt to hold the rod in place. By the way, is that what that hole was designed for? I see no reason that there would be a small bolt in the front of the block doing nothing/bolting down nothing? Also as I was un-bolting the second bolt from the pump, the pump itself was pushing out. (which tells me the rod is at the long run of it's cycle. Will I need to turn the motor so the rod flows/rides back in, to place the new pump on?
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
My "S'' shaped hoses will need to be replaced. The smaller of the two has cracks on the outside rubber. Where can I pick these up? I have a shop around the corner that deals with hydrolic lines. They have made me braided brake hoses before. Sould I see if I can heave these two made there? Or go to a pep boys/discount auto/napa store?
Safety Car
Joined: Sep 2005
Posts: 4,060
Likes: 102
From: Southeast, Tennessee
St. Jude Donor '09 thru '26
daanbc, sorry to hear about your fuel feed problems (but i know your door sills look fantastic, LOL!!). just something to think about (and maybe it just my paranoia from the "old" days), but i have always replaced that crappy little ceramic filter in the carb at the fuel line (by replaced, i mean, remove it permanently) and installed a larger in line type between the pump and the carb. i guess i can't get over the problems that those used to cause us way back when. it didn't take much to clog them (and i guess the quality of gas back then may not have been as clean as today) or perhaps dealers let their supply run low in the tanks and you sucked up a bunch of grit with your $5.00 fill up (yes, gas really was 19.9 when i started driving, lol). for whatever reason, i always feel that the larger filters provide better filtering and they certainly are easier to get to, lol.
Burning Brakes
Joined: May 2008
Posts: 1,116
Likes: 5
From: Middleburg Florida
daanbc, that bolt that doesn't hold anything? It's there to help install the fuel pump. You remove the bolt, find one the same thread and diameter but longer, and thread the longer bolt into the hole. Then you push the fuel pump push rod up as far as you can and tighten the new longer bolt just enough to hold the push rod. Then you can easily install the pump. Once the pump is bolted in place, remove the longer bolt and put the original back in so you don't have a hole in your engine for oil to run out of.
Burning Brakes
Joined: May 2008
Posts: 1,116
Likes: 5
From: Middleburg Florida
Oh, the fuel line you can get from the vette suppliers, NAPA and the like don't usually have it. If you use regular fuel line, make sure you don't kink it with the bends necessary to get from the hard line to the pump. Too bad you're not closer...I have a new pump sitting in the garage I don't need anymore...