1975 Acceleration Issues
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1975 Acceleration Issues
Hello all,
So when I bought my car, about 7 months ago, I noticed when I was above 3000 RPM it would lose power/stutter/run rough/accelerate then lose power in weird little bursts. If I kept the petal down the engine would do this so much that I would lose speed and engine revs. I figured out that if I pushed in the clutch, let the engine come back to idle, then let out the clutch and got back on it it would run fine. This only happened occasionally near or over 3000 RPM and seemed to be tied to whenever the tank was near or below 1/4. Now it is happening earlier in the revs, 2200+ or higher, and at all fuel levels. I put carb and fuel cleaner in every time I fill it up. I'm looking for suggestions as to where to diagnose the issue. My gut tells me it's a carb/fuel delivery issue, ie the carb is gunked up or the fuel filter is dirty but what does the forum think?
So when I bought my car, about 7 months ago, I noticed when I was above 3000 RPM it would lose power/stutter/run rough/accelerate then lose power in weird little bursts. If I kept the petal down the engine would do this so much that I would lose speed and engine revs. I figured out that if I pushed in the clutch, let the engine come back to idle, then let out the clutch and got back on it it would run fine. This only happened occasionally near or over 3000 RPM and seemed to be tied to whenever the tank was near or below 1/4. Now it is happening earlier in the revs, 2200+ or higher, and at all fuel levels. I put carb and fuel cleaner in every time I fill it up. I'm looking for suggestions as to where to diagnose the issue. My gut tells me it's a carb/fuel delivery issue, ie the carb is gunked up or the fuel filter is dirty but what does the forum think?
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Well this weekend I changed the oil and filter, changed the fuel filter, and changed the air filter. I drove it to work this morning and plan on doing some spirited driving home to see if it suffers the same issue or not. I couldn't replicate it this weekend, so I guess we'll see. Thanks for your help guys.
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Hello all,
Well the issue came back and was happening anytime I was over 2500 RPM. I had taken it out for some relaxing sprints before putting it away for the winter. It ran fine at first and then was happening constantly. So what do you guys think the issue could be? Fuel Pump? Fuel Sock issues? Something else?
Well the issue came back and was happening anytime I was over 2500 RPM. I had taken it out for some relaxing sprints before putting it away for the winter. It ran fine at first and then was happening constantly. So what do you guys think the issue could be? Fuel Pump? Fuel Sock issues? Something else?
Le Mans Master
Joined: Dec 2006
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Hello all,
Well the issue came back and was happening anytime I was over 2500 RPM. I had taken it out for some relaxing sprints before putting it away for the winter. It ran fine at first and then was happening constantly. So what do you guys think the issue could be? Fuel Pump? Fuel Sock issues? Something else?
Well the issue came back and was happening anytime I was over 2500 RPM. I had taken it out for some relaxing sprints before putting it away for the winter. It ran fine at first and then was happening constantly. So what do you guys think the issue could be? Fuel Pump? Fuel Sock issues? Something else?
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Well if I'm going to change the pump I might as well change the sock when I'm in there as well. Any good links with info on changing the fuel pump? I can wrench myself but I really like to follow directions. 
Also I see the following pump on Wilcox https://willcoxcorvette.com/corvette...76-replacement
Will I need anything else?
Also I see the following pump on Wilcox https://willcoxcorvette.com/corvette...76-replacement
Will I need anything else?
Le Mans Master
Joined: Dec 2006
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Well if I'm going to change the pump I might as well change the sock when I'm in there as well. Any good links with info on changing the fuel pump? I can wrench myself but I really like to follow directions.
Also I see the following pump on Wilcox https://willcoxcorvette.com/corvette...76-replacement
Will I need anything else?
Also I see the following pump on Wilcox https://willcoxcorvette.com/corvette...76-replacement
Will I need anything else?
OR, Do all at once and flush the fuel line out well.
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Thanks. I just do it all at once. The cost is cheap and if it eliminates the problem I'm all the happier.
Pro
Joined: Mar 2006
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From: SW Ohio
You will need to drop the tank to do this here is a pic of sending unit & sock
Replace the pre formed fuel lines @ the fuel pump as well
Good luck
http://www.fullthrottlecorvette.com/..._thumbnail.jpg
Replace the pre formed fuel lines @ the fuel pump as well
Good luck
http://www.fullthrottlecorvette.com/..._thumbnail.jpg
Had a 1976 L-82, 4-sp
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From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Yes, it's probably junk. I would get the KNOWN correct pump from Wilcox, if that indeed is your problem. Have you tested your fuel pump for it's rated capacity?
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I went ahead and just purchased it from Wilcox. They have been very helpful in the past and have earned my money.
I did some research and the tank seems rather easy. Disconnect the lines. Drop the tank. Remove the sender. Replace the sock. Then repeat to put it back. Does that sound right?
Also I read that some people were putting a spring around the end of the sender piper inside the sock to stop the sock from collapsing or getting sucked up into the sender. Is that something you guys have ever done?
I did some research and the tank seems rather easy. Disconnect the lines. Drop the tank. Remove the sender. Replace the sock. Then repeat to put it back. Does that sound right?
Also I read that some people were putting a spring around the end of the sender piper inside the sock to stop the sock from collapsing or getting sucked up into the sender. Is that something you guys have ever done?
Le Mans Master
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I will. The car is in storage, I'm in Ohio, so didn't want the weather to get to it. I'm planning on getting it out of storage in late February and doing all of this. Right now I've got the following scheduled:
- Change fuel pump
- Change fuel filter
- Change Sender filter/strainer
- Oil Change
- New Tires (old ones were from 2001)
- Swap out center console (old one is broken into three pieces and just hanging there)
- Install new custom made shift plate/cover with ashtray removed and cup holder/usb plug instead (being custom made by a friend of mine)
March should be interesting.
- Change fuel pump
- Change fuel filter
- Change Sender filter/strainer
- Oil Change
- New Tires (old ones were from 2001)
- Swap out center console (old one is broken into three pieces and just hanging there)
- Install new custom made shift plate/cover with ashtray removed and cup holder/usb plug instead (being custom made by a friend of mine)
March should be interesting.