63 FI problem
Thread Starter
Racer
Joined: Feb 2008
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From: Greer South Carolina
63 FI problem
I just finished my 63 FI vette and have logged about 950 miles. The 2nd cable that goes from the distributor to the high pressure fuel pump has broken. This is my first fuelie and I don't have any past experience with this type of problem. Anyone out there that knows of this problem and has a fix, please let me know. Dave
Thread Starter
Racer
Joined: Feb 2008
Posts: 304
Likes: 1
From: Greer South Carolina
63 FI problem
Both cables are broken in the middle. I bought this car 3.5 years ago and it came with a truck load of new parts that were bought around 1971 & 72. Both cables were in there original GM boxes.
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Two things:
1. You need to make a subjective evaluation of how easy is it to turn the pump by hand. Put a new, bare cable in the pump shaft and turn it with just your thumb and forefinger. If the pump is set up with proper gear clearances and has no other issues, it should turn VERY easily.
2. When you installed the two cables that have broken, did you lubricate them? They need grease to prevent wear. A generous amount of wheel bearing grease works well.
Jim
1. You need to make a subjective evaluation of how easy is it to turn the pump by hand. Put a new, bare cable in the pump shaft and turn it with just your thumb and forefinger. If the pump is set up with proper gear clearances and has no other issues, it should turn VERY easily.
2. When you installed the two cables that have broken, did you lubricate them? They need grease to prevent wear. A generous amount of wheel bearing grease works well.
Jim
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The most frequent cause of a cable breaking in the middle is friction against a rough (or dry) side wall of the cable housing. Overstress breaks usually occur at the distributor end.
Although I've never disagreed with Jim before, I wouldn't say that normal pump seal and gear drag can be very easily overcome with two fingers on a drive cable. The pump should turn over smoothly without any binding, but not very easily.
Although I've never disagreed with Jim before, I wouldn't say that normal pump seal and gear drag can be very easily overcome with two fingers on a drive cable. The pump should turn over smoothly without any binding, but not very easily.
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From: Taylor Michigan
Not correct, but you can still drive the car without the housing over the cable. In fact its much easier to remove and install the cable with no housing interfering. I ran mine several years without the housing, just too lazy to replace it at times. Currently its installed for anyone wondering....
.
.
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St. Jude Donor '07
Not correct, but you can still drive the car without the housing over the cable. In fact its much easier to remove and install the cable with no housing interfering. I ran mine several years without the housing, just too lazy to replace it at times. Currently its installed for anyone wondering.....
.
i made an 'emergency' cable out of a broken cable by soldering a piece of copper tubing as a splice over the broken portion and ran it without the casing.
emergency cable or regular cable, it will run fine and stay in place without the casing.
try it without the casing and you can see what the cable is doing when the engine runs. it may give you a hint of what's wrong if it flails about.
Bill
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From: Greenville, Indiana
i made an 'emergency' cable out of a broken cable by soldering a piece of copper tubing as a splice over the broken portion and ran it without the casing.
emergency cable or regular cable, it will run fine and stay in place without the casing.
try it without the casing and you can see what the cable is doing when the engine runs. it may give you a hint of what's wrong if it flails about.
Bill
That was good thinking.
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The key, though, is for the pump to turn smoothly, as Jerry rightfully pointed out.
Jim
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Um....the engine WILL run fine with only the drive cable and no sleeve, HOWEVER, the drive cable WILL come out of your distributor if you run the engine to high speed.................say when you downshift and floor it to PASS another car....the engine will die just as you pull alongside!
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From: Inverness FL
St. Jude Donor '07
Um....the engine WILL run fine with only the drive cable and no sleeve, HOWEVER, the drive cable WILL come out of your distributor if you run the engine to high speed.................say when you downshift and floor it to PASS another car....the engine will die just as you pull alongside!
Bill
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From: Greenville, Indiana
I had it happen to me, twice. It put some permanent kinks in the cable. I then decided it wasn't a good idea to run without the casing except in an emergency or diagnosing. That's back when the cables cost maybe a buck and change apiece.
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St. Jude Donor '07
Bill
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From: Granbury Texas
The main reason for running without the jacket is to run with a clean (ungreased) cable, so when you park the car, just put the FI drive cable in your pocket and walk away. To steal your car they now need a tow truck.
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From: Inverness FL
St. Jude Donor '07
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Those carbon bushings NEVER need replacing unless some Gyro Gearloose has broken one in the past while removing the seal. If one of your bushings is missing, I will give you contact info for the two machinists who have jigs to install them properly. By the way, I am not one of them... and neither is Paragon.
Thread Starter
Racer
Joined: Feb 2008
Posts: 304
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From: Greer South Carolina
63 FI problem
Unless you are a very experienced machinist, please don't attempt this.* Those two carbon bushings were align-bored after installation to keep the gear centerlines perfectly parallel and properly spaced.* This boring requires close tolerances that you can't duplicate at home.Those carbon bushings NEVER need replacing unless some Gyro Gearloose has broken one in the past while removing the seal.* If one of your bushings is missing, I will give you contact info for the two machinists who have jigs to install them properly.* By the way, I am not one of them... and neither is Paragon.
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Jim
Last edited by jim lockwood; Jun 28, 2009 at 10:09 PM.