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Mechanical Fuel Pump Installation....HELP!

vetteboy86

Well-known member
Joined
May 26, 2003
Messages
2,760
Location
IN
Corvette
1986 Black "Indy 500 Pace car replica"
I am trying to put a new fuel pump on a 71 454. The previous owner had a holly pump on there, and had rubber hoses all over. I purchased a replacement delco and original fuel line to replace the rubber hoses.

I pulled the old pump off no problems. I tried putting the new pump on, but then realized that the rod that works the pump armature had slipped all the way down. I then took the plumbing type plug off and that rod wanted to slip out.

I knew I had to get this pushed up so that I could put the new pump on. I took a phillips screw driver and pushed the rod up into the engine. It moved farily easily and then hit a friction point where it didn't want to slide as easy.

Well now the rod is STUCK in motor. It wont slide out, and I cannot push it in any further by hand. I turn the motor over and it wont turn. My guess is that it is somehow stuck, but not touching the cam lobe! How did this happen, that is hardened steel, theres no way I could have bent it with a screw driver.

It is hard as heck to get anything on it to pull it out. I was think I could drill the end, tap, and screw a long bolt in, that way I would have something to pull against. My only question with that is, can I drill that rod?

Can anyone suggest anything, or give advice PLEASE??

Craig
 
that rod rides in a machined bore. it should not be cocked sideways or in a bind. you said the motor will not turn over, how did you try and spin it?? i would pull the spark plugs and put a wrench on the damper bolt. try rolling the motor forward and back, it should move at least one way and free up the rod. also there are two bolts on the front of the block, if you remove one and install a longer bolt HAND TIGHT it will hold the rod in place until you replace the pump. also when you get the rod out, roll the motor around until the cam lobe allows the rod to slide into the motor to the max extent. this lowers the amount of spring pressure on the pump arm you have to fight when getting the pump mounted. please for the love of GOD, do not drill the rod!
 
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I had a heck of a time turning it over with at the damper bolt. I heard stories about snapping the bolt off from a few people. The starter turns the motor over easy. I probably don't have enough leverage. This bolt in front of the engine, is it possible that is holding it in place? What I dont understand is I didn't mess with any bolt, and it appeared that the other pump worked fine.

I am really at a miss on what to do and how to get this rod out. WHen the motor is turned over by the starter, the rod does NOT move in either direction? If it is slightly bent, I have no idea how it got that way.

When I slid it up, it slid freely, and then met some resistance, and at that point it was stuck.
 
Makes no sense. Other then that bolt there is nothing to hold it. Considering its not moving it may not be up high enough or the other pump used a shorter rode...if thats possible.

Do the ends of the two pumps extend the same distance? If so calculate the distance of the arm on the new pump and measure the distance up to the piston. Is it going to make contact? Is the piston up too high or not high enough? if the distance seems right...you may want to install the new pump and see if it works. Bit risky with out known what caused the rod to bind.

Remove the bolt that holds the piston...does it look like it made contact? If so try a proper length bolt.

Jim
 
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The arms on the two pumps look identical, that is one of the first things I looked at. With the rod in its current position, the pump will not bolt up to the block easily. I would say there is a good half inch gap. I have no idea what put it in this bind, or how it is even in this bind.

I will remove the screw in the front as mentioned and see if there are signs. It would be nice if it just fell out when I loosened this. However since I never touched it and the previous pump worked, I doubt it.

Any ideas on how to get this thing out??
 
So there would be a 1/2 inch of air between the pump and piston? Or you need to compress the pump arm a 1/2 inch to bolt it on?

try tapping the block near the opening. it should come out...piston is heavy.
 
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When I go to put the pump on, the pump is about a half inch away from the block, due to the rod. I would imagine that when this rod is all the way up, the pump would come close to just going right on.

I tried tapping that area, last night, but wasn't able to get any good hits on it. I will try that again.

Any more ideas??????
 
Long shot. Do you have a shop vac? Or something that would provide serious suction? I assume the rod is a tight fit in the bore. get a hose that also fits tightly in the bore and rig something up to connect the hose to the shop vac. Maybe you can suck it out.

You said you can turn the engine over so its not getting hung up on anything. Why not just put the old pump or new pump in there and get it running. should push it out.

Jim
 
What if you take the bolt out in the spot used to hold the rod in place. Maybe you could get something else in through that hole to give it a bit of help.

I looked around a bit. Sounds like you need to take that bolt out. From what I have read crud could have loosened up and fallen into the chamber jamming the piston.

Everything I read says not to put much pressure on the rod through the bolt hold...it will bend.

Jim
 
there is an access plate held on by two small bolts and the fuel pump bolts; remove it and you should be able to grab the push rod to pull it out with vise grips and replace it.
 
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I can't believe that something could bend that rod that easily?

There wasn't an access plate behind the pump between the pump and the block. So I have as much access as i'm gonna get.
 
When I go to put the pump on, the pump is about a half inch away from the block, due to the rod. I would imagine that when this rod is all the way up, the pump would come close to just going right on.

I tried tapping that area, last night, but wasn't able to get any good hits on it. I will try that again.

Any more ideas??????

The more I read this the more I think you should put the pump on and turn it over. You were able to turn the engine over with the starter....correct? If so nothing is jammed....and for what its worth there is nothing there to jam.

From what you have said there is no way you bent the rod. Needing to compress the pump arm about 1/2 inch to get it on is about right. There is always compression by the pump holing the rod tight to the cam.

I can't say why its stuck. If you are really concerned take it to a shop. I hear the way to get it out is by welding something to the rod and pulling on it. Unless you have a welder.


See link...same problem
http://www.chevelles.com/forums/showthread.php?t=178859
 
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I was just told that by a friend. I really see it being a hard time getting something welded on the end of it, but that is better then nothing. LIke you said, I cannot say why it is stuck either.

This friend also told me that if the rod wasn't pressed firm against the lobe that when it came around it could have bent it slightly, but the rod was stuck before we turned the motor over.

If any more suggestions come up lease let me know, otherwise I will keep you all posted.

Craig
 
I was just told that by a friend. I really see it being a hard time getting something welded on the end of it, but that is better then nothing. LIke you said, I cannot say why it is stuck either.

This friend also told me that if the rod wasn't pressed firm against the lobe that when it came around it could have bent it slightly, but the rod was stuck before we turned the motor over.

If any more suggestions come up lease let me know, otherwise I will keep you all posted.

Craig

No way you bent it because it was tight to the lobe. The pump arm has a spring and always keeps it tight to the lobe. there is no play.

Only possiblity is you freed up some crud and its jammed between the the rod and wall.

Why don't you get the car started with out the pump. Feed gas into the carb to keep it going. see if it frees up when it gets good and hot. Oil should come gushing out of that opening....maybe freeing up rod.

Jim
 
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Well I ended up working it while the motor was turning over and got it moving. It still isn't moving as freely as I believe it should, but the pump is on. With the motor turning over, I can feel the pump working by touching the pump housing.

Now all I have to do is get some gas in the tank and see if she will pull fuel. Once this is done, I will update everyone that helped.

Once again, I really appreciate all the help and suggestions. Some how through the tough and unexpected CAC always gets me through!

Craig
 
I had this same thing happen once.I dont know if it had junk in it, or just had a hydraulic lock. I pulled the plate off, and just worked and twisted it with vise grips, until I finally got it loose. Then after I got it shoved all the way back in, I used a longer bolt in the front to hold the rod in until I got the pump back on.Something else to consider, that if it came down to it and you could never get the rod loose, you could always install a pump block off plate, and just run an electric fuel pump.Anyhow, glad to see you got it fixed :):w
 
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Yeah it was the weirdest thing. I have given the electric pump much thought. Hopefully it becomes lubricated and loose once again.
 
If you ever have to do it again. Stick some grease on it so it holds in the hole or use that bolt. Mind you when I was looking around it said in a few places that the bolt hold is only on a small block.

I think it will be fine once the oil gets to it. You may want to change that too in case it is crud.

Jim
 
Wow,
That's quite an ordeal. I just replaced the stock fuel pump with a Holley. I'm a bit confused as to what would have gotten stuck. I don't know about BB, but my SB had a plate between the fuel pump and the block. 2 bolts held on the fuel pump, 2 bolts held on the plate.
Anyway, I had the opposite problem. When i removed the old pump, the rod fell out and hit me in the head. I slid it back in, and it fell right back out. I called a friend of mine that is a mechanic and has done a lot of work on Corvettes. He said the trick to keeping the rod in place is to coat it with grease. Then it slides in smoothly and stays there long enough for you to get the new pump bolted on.
There is NO way you bent the rod while putting it in. When you had it out, did it look bent? And did the new fuel pump come with a new rod or were you re-using the old one? The Holley pump i bought did not come with a rod, so i used the stock and it was a perfect fit.
I also had to compress the pump's arm about 1/2 an inch.
Another trick, i used longer bolts to install the pump. The old bolts were about 1/2 long, but the hole was 1 and 1/2 inches deep. So i bought two 1 inch stainless steel bolts, and compressed the arm by alternating which bolt i tightened.
It was a pain, but only took me a day.
Good luck, and let us know how that rod looks when you get it out.
 
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Bad news. The pump is not working. The first thing I did was put a vacuum pump on the line from the tank right at the pump to pull fuel. It did so I figure the line is good. The next thing I did was hold my finger over the discharge side of the pump to see if it was pushing anything and it was not.

I removed the pump, it came off pretty easy, and that rod is still there. I pushed on it with a screwdriver while my dad turned the car over, and it wont move.

Well i'm at a loss now. I am not sure what to do. I know I could try for weeks to get that rod out of there. Or maybe I could just throw an electric pump at it. If I bought a cheap pump I could hook it up to get the car running, then once the oil and everything gets up to temp, see if the rod is free. If it isn't I could permanently use th electric pump.

Anyone see any problems with this? Also can anyone recommend a pump to use?

Craig
 

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