1968 327 , Carburetor question
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
1968 327 , Carburetor question
My 68 coupe with small block has a stock Rochester that was completely restored and then tuned for me by Lars.
Ran fine all last year and this year until 2 weeks ago when I last filled the tank.
Had to get towed today as it runs for a mile and then stalls and sputters and dies. I let it sit for a few minutes and it runs fine again for another mile or so.
I think I have water in the carb bowl and when I drive it sloshes around and stalls out or I may have dirt and sediment by the needle and seat.
My question is , how do I get the water out of the carb without screwign up all the settings and adjustment Lars did for me that made it run perfect like a swiss watch until this happened?
Is there a filter on the side of the carb where the fuel line enters, other than the can type mounted on the front of the engine in the fuel line?
Thank you in advance,
Kurt
Ran fine all last year and this year until 2 weeks ago when I last filled the tank.
Had to get towed today as it runs for a mile and then stalls and sputters and dies. I let it sit for a few minutes and it runs fine again for another mile or so.
I think I have water in the carb bowl and when I drive it sloshes around and stalls out or I may have dirt and sediment by the needle and seat.
My question is , how do I get the water out of the carb without screwign up all the settings and adjustment Lars did for me that made it run perfect like a swiss watch until this happened?
Is there a filter on the side of the carb where the fuel line enters, other than the can type mounted on the front of the engine in the fuel line?
Thank you in advance,
Kurt
Melting Slicks
Joined: Dec 1999
Posts: 2,157
Likes: 0
From: Pensacola FLA
My 68 coupe with small block has a stock Rochester that was completely restored and then tuned for me by Lars.
Ran fine all last year and this year until 2 weeks ago when I last filled the tank.
Had to get towed today as it runs for a mile and then stalls and sputters and dies. I let it sit for a few minutes and it runs fine again for another mile or so.
I think I have water in the carb bowl and when I drive it sloshes around and stalls out or I may have dirt and sediment by the needle and seat.
My question is , how do I get the water out of the carb without screwign up all the settings and adjustment Lars did for me that made it run perfect like a swiss watch until this happened?
Is there a filter on the side of the carb where the fuel line enters, other than the can type mounted on the front of the engine in the fuel line?
Thank you in advance,
Kurt
Ran fine all last year and this year until 2 weeks ago when I last filled the tank.
Had to get towed today as it runs for a mile and then stalls and sputters and dies. I let it sit for a few minutes and it runs fine again for another mile or so.
I think I have water in the carb bowl and when I drive it sloshes around and stalls out or I may have dirt and sediment by the needle and seat.
My question is , how do I get the water out of the carb without screwign up all the settings and adjustment Lars did for me that made it run perfect like a swiss watch until this happened?
Is there a filter on the side of the carb where the fuel line enters, other than the can type mounted on the front of the engine in the fuel line?
Thank you in advance,
Kurt
I had a similar problem and it turned out to be the fuel pump.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
If it happened after your last fill up, you may have gotten bad gas. Fuel storage tanks at older stations have rust, and if you fill up when the tank is low, you can get a tank full of sediment. It will cause exactly the problems you describe. The fuel will slowly seep through to get you going, then starve out. After a while of sitting, enough will have seeped through to start again.
Try to get a look inside your fuel tank and see. My '81 has an easy to remove fuel filler that gives about an 8" diameter hole to look through, but I have heard earlier models do not have such easy access.
If this is indeed the problem, you will need to drain and clean the tank, buy a new fuel strainer sock in the fuel tank and replace the fuel filter on the carb.
I doubt the carb itself is the problem, but if it needs work, just seat, count and record turns on all adjustments you remove. Reassemble with the same settings.
God bless, Sensei
Try to get a look inside your fuel tank and see. My '81 has an easy to remove fuel filler that gives about an 8" diameter hole to look through, but I have heard earlier models do not have such easy access.
If this is indeed the problem, you will need to drain and clean the tank, buy a new fuel strainer sock in the fuel tank and replace the fuel filter on the carb.
I doubt the carb itself is the problem, but if it needs work, just seat, count and record turns on all adjustments you remove. Reassemble with the same settings.
God bless, Sensei
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Thank you for the reply.
Why would the fuel pump be intermittent.
This car was completely restored 2 years and approx. 1,500-2,000 miles ago including the engine and a new AC Delco factory correct fuel pump.
Not doubting you , just trying to learn. My son said fuel pump also but what confuses me is that it runs fine and then doesn't run.
Wouldn't a fuel pump give trouble all the time, that's why I suspected water but I am guessing.
Kurt
Why would the fuel pump be intermittent.
This car was completely restored 2 years and approx. 1,500-2,000 miles ago including the engine and a new AC Delco factory correct fuel pump.
Not doubting you , just trying to learn. My son said fuel pump also but what confuses me is that it runs fine and then doesn't run.
Wouldn't a fuel pump give trouble all the time, that's why I suspected water but I am guessing.
Kurt
Last edited by ksbunting; Aug 9, 2009 at 10:44 PM.
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Thank you sensei
I can see into the tank.
I can see the fuel sock; what should I be looking for or should I try to get my hand in there and feel the sock for sludge.
Can the sock be replaced in the tank without removing the entire fuel pickup unit?
Thanks for the replies, I appreciate the help
Kurt
I can see into the tank.
I can see the fuel sock; what should I be looking for or should I try to get my hand in there and feel the sock for sludge.
Can the sock be replaced in the tank without removing the entire fuel pickup unit?
Thanks for the replies, I appreciate the help
Kurt
Race Director
Joined: Jun 2005
Posts: 10,189
Likes: 206
2018 Corvette of Year Finalist
2017 C3 of Year
Thank you sensei
I can see into the tank.
I can see the fuel sock; what should I be looking for or should I try to get my hand in there and feel the sock for sludge.
Can the sock be replaced in the tank without removing the entire fuel pickup unit?
Thanks for the replies, I appreciate the help
Kurt
I can see into the tank.
I can see the fuel sock; what should I be looking for or should I try to get my hand in there and feel the sock for sludge.
Can the sock be replaced in the tank without removing the entire fuel pickup unit?
Thanks for the replies, I appreciate the help
Kurt
Looking down through the fuel door really doesn't help. The clog will be hidden by the outer layer. Mine looked like new through the door but after removing it that's what I found. I replace the entire fuel sender. No more troubles!
WB
Melting Slicks
Joined: Dec 1999
Posts: 2,157
Likes: 0
From: Pensacola FLA
Thank you for the reply.
Why would the fuel pump be intermittent.
This car was completely restored 2 years and approx. 1,500-2,000 miles ago including the engine and a new AC Delco factory correct fuel pump.
Not doubting you , just trying to learn. My son said fuel pump also but what confuses me is that it runs fine and then doesn't run.
Wouldn't a fuel pump give trouble all the time, that's why I suspected water but I am guessing.
Kurt
Why would the fuel pump be intermittent.
This car was completely restored 2 years and approx. 1,500-2,000 miles ago including the engine and a new AC Delco factory correct fuel pump.
Not doubting you , just trying to learn. My son said fuel pump also but what confuses me is that it runs fine and then doesn't run.
Wouldn't a fuel pump give trouble all the time, that's why I suspected water but I am guessing.
Kurt
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
Not your carb. thats for sure. If you fuel pump is not working fully it can pump at a rate slower than the engine needs. The reserve is in your carb bowl. Once it gets used, which doesn''t take long at all, then it will sputter and die. Maybe when the car is idling it uses less fuel and allows the bowls to fill. Then you drive it and the bowls deplete and it quits. I could be wrong about the exact details but I doubt it is the carb. Of coarse you could have a blocked line as others have said and have the same results.
With a cold engine (safety), take the line from the pump to the carb loose, and pull your coil wire so the car doesn't start. With someone cranking the engine view how much the carb pumps. It should be a lot more than the carb needs. That's why many cars use the bypass lines as it keeps pressure off the pump. Anyway be careful. You don't need fuel all over the car.
With a cold engine (safety), take the line from the pump to the carb loose, and pull your coil wire so the car doesn't start. With someone cranking the engine view how much the carb pumps. It should be a lot more than the carb needs. That's why many cars use the bypass lines as it keeps pressure off the pump. Anyway be careful. You don't need fuel all over the car.
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Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
Thank you sensei
I can see into the tank.
I can see the fuel sock; what should I be looking for or should I try to get my hand in there and feel the sock for sludge.
Can the sock be replaced in the tank without removing the entire fuel pickup unit?
Thanks for the replies, I appreciate the help
Kurt
I can see into the tank.
I can see the fuel sock; what should I be looking for or should I try to get my hand in there and feel the sock for sludge.
Can the sock be replaced in the tank without removing the entire fuel pickup unit?
Thanks for the replies, I appreciate the help
Kurt
God bless, Sensei
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The second thing to do is to remove the fuel filter in the carb inlet to see what is there. If you do have a fuel tank sediment problem, it will show up in the fuel filter; If you don't have a tank problem, the fuel filter will be clean. Also, the filter will show beads of water on it if you have a water-in-tank problem. Should that be the case, just buy a bottle of "Heet" at the auto parts store. It is basically alcohol which will mix with gas and water so that the water will dissolve into the fuel. It may not be as 'potent' as dry fuel, but it will burn, just the same. The test with the accelerator pump [mentioned above] is a good one, but it may just be indicative of the fuel filter being clogged. Do the accel. pump test first...if it fails that test, take the fuel filter out. Good luck. [P.S. I don't believe that your carb is the problem either...but it could be, if it got some cr@p into it.]
Race Director
Joined: Jul 2001
Posts: 15,892
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Don't rule out heat related ignition problems, bad resistor wire or coil for instance.
Are you sure your gas cap is venting properly? Try driving with it in place but not secured to allow air to enter the tank. Easy thing to try.
Are you sure your gas cap is venting properly? Try driving with it in place but not secured to allow air to enter the tank. Easy thing to try.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
If you got a load of fuel that is high in alcohol your engine could be vapor locking. A non invasive way would be to just siphon the fuel out of the tank and get some new gas and run the car and see if that fixes it.
If you do siphon the fuel out mix it up in the tank first and then put the first bit out into a large clear container and let it sit over night and look for separation. I had the same thing happen 10 years ago and there was a clear separation and I was told by the gas station that the fuel had an additive called benzine (think that was it) and sometimes if they get too much in it will separate. I do know that it would burn the crap out of your skin whatever it was.
If you do siphon the fuel out mix it up in the tank first and then put the first bit out into a large clear container and let it sit over night and look for separation. I had the same thing happen 10 years ago and there was a clear separation and I was told by the gas station that the fuel had an additive called benzine (think that was it) and sometimes if they get too much in it will separate. I do know that it would burn the crap out of your skin whatever it was.
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Thanks everyone for the input.
As soon as I can get some garage time I am going to go out and try some of these suggestions to see if I can find out what is causing my problem.
Kurt
As soon as I can get some garage time I am going to go out and try some of these suggestions to see if I can find out what is causing my problem.
Kurt
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
It is fixed and running well.
The culprit was the rubber fuel feed line going from the metal fuel line attached to the frame, over to the fuel pump.
It had a kink in it and the rubber was starting to crack.
Replaced it with new style rubber fuel line $7.50per foot) that can handle the ethanol and looped it so as to eliminate possibily of kinking again. Took it out for a run and runs great, no bog, no hesitation. Glad it wasn't that carb or needle and seat inside the carb.
Thank you to all for your input.
Kurt
The culprit was the rubber fuel feed line going from the metal fuel line attached to the frame, over to the fuel pump.
It had a kink in it and the rubber was starting to crack.
Replaced it with new style rubber fuel line $7.50per foot) that can handle the ethanol and looped it so as to eliminate possibily of kinking again. Took it out for a run and runs great, no bog, no hesitation. Glad it wasn't that carb or needle and seat inside the carb.
Thank you to all for your input.
Kurt
Instructor
Joined: Aug 2009
Posts: 119
Likes: 0
From: Demotte In
I had a similar problem and it turned out that the shims wore off at the bottom of the distrbutor- I replaeced the distributor with a protronics II and it runs just fine except for a little rich on the carb.
