I have a Chevy 454 that was being fed by an electric fuel pump. I needed to utilize the return line for the fuel tank, which was capped off by the previous owner. The place for the mechanical fuel pump on the 454 had a plate over it. When I removed it, there was no fuel pump push rod behind it. Is it possible to install a push rod without tearing down the engine?
If not, is there a way to make the mech fuel pump diaphragm remain open? Basically, I installed this fuel pump because my Firebird's return fuel line was capped off. When the cap fell off draining my tank, I decided to fix it by installing the mech fuel pump. So, I planned to run both the mech and elect fuel pumps.
The electric pump will push right past the meachanical one. You don't need to mess with "holding the diaphragm open." A Chevy expert will probably be able to tell you that the fuel pump push rod simply slides in wouthout needing to open up the engine.
not that I know of. you have to fix the prob removing the cover is not bad and hard to do bypassing it is the only way. you can run a electric through a mechanical if the pump if working if either one fails then the engine will run but if both fails then you know the rest.
Yup, just remove the threaded plug below where the fuel pump bolts on, put some moly on each end of the pushrod and a dab of wheel bearing grease on the shaft and slide it in. The grease helps keep the pushrod up out of the way of the fuel pump arm when installing the pump. Don't forget to put some sealant on the plug when you reinstall it.
I don't know if the BBC is the same as a SB but you can install a longer bolt into a thread hole in the front of the block to hold the rod up in place until you get the pump installed(on SB). Just don't forget to remove it and reinstall the shorter one after or there will be trouble in river city.
Thanks, everyone. I got it installed. I used the screwdriver method to keep the pushrod out of the way. Still no start on the car, though. Now, I have no clue why. Since my gas gauge is dead, and I have no idea how much fuel I lost when the return line issue occurred, I'm going to try to put a gallon or so in, and see if that is the problem. After that, I can only guess it is a bad new mech fuel pump. Any other ideas as to what the issue is? All the fuel lines I put in were bent correctly with no crimps.
Again, are you getting fuel at the carb inlet? Assuming you've drained the fuel lines installing the new pump, it will take a while to get fuel through the lines, if in fact you have fuel in the tank.
Simple stuff first...
With a Quadrajet you can use a 1/4" tip funnel and pour about 1/2 cup of fuel into the fuel bowl through the vent tube at the front of the carb. This is enough to start the car and run several seconds until fuel pulls.
Did you pull your coil wire or distributor harness while working?
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching
Ok. I got the fuel pump running, push rod installed, and the car starts now. BUT...
Now, the car does not rev correctly. It did before with the electric pump, and the only change is new fuel lines to the new mech fuel pump. Now, it idles very slowly, and pressing the gas peddle causes the car to cut off. It seems like it is not getting enough fuel. Would the fuel pump I got not be powerful enough for this engine? It is said to go with this engine. Is there a way to adjust the fuel pump? Or, do I need to adjust the carb to the new setup?
Thanks for any help, More info to come, if needed.
I'd look for an obstruction in the fuel line such as thread sealant, fuel filter in backwards, stuck float, etc. Check your fuel flow, it should be a good volume out of the pump.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching
I would look around for something you may have accidentally moved or unhooked while you were working. Check all the plug wires closely.... Look for vacuum leaks....
Did you use pre-formed fuel lines? If so, did you use compressed air to remove the media from the lines? And did you check closely for kinks in the line or places it may have gotten pinched?
Along with the suggestions above...
It doesn't take much fuel to idle, so you may have unrelated issues. Check that the distributor is not loose, that the cap is on square and tight, etc.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching
The lines were not pre-formed. I bent the lines, and was very careful not to have any crimps by bending a little, moving the bending tool a little upstream, and bending a little more.
I was working in close proximity to a couple of the plug wires... I'll check those and the distributor out. The distributor is at the firewall next to the windshield wiper motor, so I hope it isn't loose. If it is... ugh
I checked all the plugs, and nothing was loose. I double checked the fuel lines and there were no kinks, and I found no vacuum leaks.
I plugged the electric fuel pump back up by itself, isolating the mechanical pump, and the car started fine and idled fine. Ugh.
Could it be that this Chevy 454 pump works best with a non-vented Chevy pickup gas tank, and thus the return line is not getting enough back pressure from the vented gas cap on the Firebird gas tank, and subsequently pushing too much gas back through the return line?
Disregard the last...the car won't start now. I go TDY Monday for a week and then start Weapons School after that, so my time is now gone. After talking with a friend, they recommended me to a hotrod shop (cchotrods.com) here in town that I never knew existed. So, I think I'm going to have them work on it while I am gone, and hopefully come back to a fully working Firebird. I don't want the car to sit until June 14th when I graduate, and then have time again to work on it.
Thank you all so much for the help. You guys rock.
Venting is not just good, it's necessary. Without venting the tank will collapse.
Sometimes you just need help to work through an issue, but this one should have been pretty simple if you had time to take the steps to test it all the way through. But in any case, coming back to a working car is a good thing too.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching
Just to keep things interesting, crapping out on light throttle wouldn't be caused by a problem with fuel delivery to the carb. At this point, the bowl is full--or it should be. You could disconnect the fuel line, and the vehicle should "goose" for at least a couple of throttle raps.
Along with many other go/no-go tests I'd make, for the no goose, the first thing I would check is accelerator pump shot.
Should be is the operative phrase. Isn't full is most likely from the sound of it since it will barely idle.
But Amervo has a point, you could fill the carb float bowl manually through the bowl vent like Vikki mentioned earlier to verify a fuel delivery problem. If it acts normal for the first ten seconds or so, then you definitely aren't getting enough fuel. Any chance you have the lines into and out of the mechanical pump hooked up wrong? The electric pump may have just enough pressure to overcome the mechanical pump but not enough to do more than idle.
I have to admit...I did have the mech fuel pump connected incorrectly initially. That was the problem once I got the fuel pump pushrod in. I did get about a 1/2 cup of fuel into the carb before attempting to get it running, but it sputtered. To me, it seemed like something was up with the carb.
Headed out of town today. You guys have a great week! Dave
How did you get a 1/2 cup of fuel in the carb? Dump it? This a method for testing go/no-go for the engine fireing up. It ends there; you cannot assess engine performance without a pressurized fuel source on an engine designed to use a pressurized fuel source.
I quit tech advice because of my general poor additude--unlike the kind, compassionate persons who always show the utmost respect, I'm pretty nasty with a super chitty additude. Even so, it's obvious that someone has to give some technical advice, or this board is going to degrade lower than its present status. I also would like to say it's fasinating that with all the alledged expertise around here, that there could be some ground zero instruction. Even more fasinating is that the need for ground zero informtion isn't recognized. Then again, in my professional experaince with watching others troubleshoot, the lack therof doesn's surprize me.
Anyway, if you haven't done so--and something tells me you haven't--you need to check the volume of fuel coming out of the end of the fuel line, the end that attaches to the carb.
Only one question because anything more will be waste of my time:
Have you verified the fuel flow coming out of the gas line?
This is a yes or no. The way you answer has a lot of bearing on the next step.
Disregard the last...the car won't start now. I go TDY Monday for a week and then start Weapons School after that, so my time is now gone. After talking with a friend, they recommended me to a hotrod shop (cchotrods.com) here in town that I never knew existed. So, I think I'm going to have them work on it while I am gone, and hopefully come back to a fully working Firebird. I don't want the car to sit until June 14th when I graduate, and then have time again to work on it.
Thank you all so much for the help. You guys rock.
How did you get a 1/2 cup of fuel in the carb? Dump it? This a method for testing go/no-go for the engine fireing up. It ends there; you cannot assess engine performance without a pressurized fuel source on an engine designed to use a pressurized fuel source.
I quit tech advice because of my general poor additude--unlike the kind, compassionate persons who always show the utmost respect, I'm pretty nasty with a super chitty additude. Even so, it's obvious that someone has to give some technical advice, or this board is going to degrade lower than its present status. I also would like to say it's fasinating that with all the alledged expertise around here, that there could be some ground zero instruction. Even more fasinating is that the need for ground zero informtion isn't recognized. Then again, in my professional experaince with watching others troubleshoot, the lack therof doesn's surprize me.
Anyway, if you haven't done so--and something tells me you haven't--you need to check the volume of fuel coming out of the end of the fuel line, the end that attaches to the carb.
Only one question because anything more will be waste of my time:
Have you verified the fuel flow coming out of the gas line?
This is a yes or no. The way you answer has a lot of bearing on the next step.
Hi Amervo,
I appreciate the time you took with the post and the recognition that I do need pretty basic help. I was getting sufficient fuel through the line, and I used a 1/4 funnel to get the fuel into the carb to get it to start. (New fuel lines, lots of air, and thus needed it to start.)
The car is in the shop now, and they are doing many of the projects I had planned to have completed before starting USAF Weapons School. Now that I am in the school, I pretty much go to work, and come home only to sleep. The first week, we averaged 16+ hour days. This is the advertised time requirement, so I plan to be unable to do anything other than drive my FB to work and back, except on Sundays. So, I decided on the shop option.
Thanks for the help, and sorry for wasting your time.
