Fuel Leak - fuel pump
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,487
Likes: 1
From: Sydney
Fuel Leak - fuel pump
Hi all,
Well I go down to the garage today and it smells really strongly like fuel. I look under the car and under the front RHS is a puddle of gas! I have a look under the car and it appears to be dripping from the fuel pump.
At first I figured it was the rubber hoses going to the base of the fuel pump, but after wiping the pump area clean and watching a couple of times it appears that the leak is actually coming from the top of the pump which looks like a large o-ring seal, around the top of the cylindrical part of the pump.
The car is a stock '70 350 SB.
On to my questions, Is there actually a seal there, and is the seal replacable, or do you have to change the whole pump?
How much trouble is it to replace, would I have to remove the AirCon compressor or can you take it out from below?
Finally the thing that troubles me is that the pump looks quite new, is it common for the pumps to fail here, or does it suggest it is just a faulty/cheap unit?
Stay cool,
cosmicvette
Well I go down to the garage today and it smells really strongly like fuel. I look under the car and under the front RHS is a puddle of gas! I have a look under the car and it appears to be dripping from the fuel pump.
At first I figured it was the rubber hoses going to the base of the fuel pump, but after wiping the pump area clean and watching a couple of times it appears that the leak is actually coming from the top of the pump which looks like a large o-ring seal, around the top of the cylindrical part of the pump.
The car is a stock '70 350 SB.
On to my questions, Is there actually a seal there, and is the seal replacable, or do you have to change the whole pump?
How much trouble is it to replace, would I have to remove the AirCon compressor or can you take it out from below?
Finally the thing that troubles me is that the pump looks quite new, is it common for the pumps to fail here, or does it suggest it is just a faulty/cheap unit?
Stay cool,
cosmicvette
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
I think they tend to leak from that top hole if the diaphragm goes, but don't quote me on that 
If you need a new pump, I have a stock style one from Napa on my car that I'd be willing to sell you since I got a new high performance unit that I need to get to installing anyhow How does $20 + shipping sound? It only has around 1000 miles on it or so, but I got it before I was planning on swapping to a much higher output engine
-dath
If you need a new pump, I have a stock style one from Napa on my car that I'd be willing to sell you since I got a new high performance unit that I need to get to installing anyhow How does $20 + shipping sound? It only has around 1000 miles on it or so, but I got it before I was planning on swapping to a much higher output engine -dath
Drifting
Joined: May 2003
Posts: 1,634
Likes: 2
From: Melbourne, Victoria, Australia, the World
Cosmic can probably pick up one locally for less than the shipping to Australia. Lots of Chev parts here.
Stock fuel pumps are sealed units and you will have to replace it. Pumps do wear out and fail. Quality units should last at least 10 years and most last the (expected
) life of the car.
Not sure how easy it is to replace from below. If you can't find one in Sydney I can recommend several suppliers in Melbourne.
Stock fuel pumps are sealed units and you will have to replace it. Pumps do wear out and fail. Quality units should last at least 10 years and most last the (expected
) life of the car.Not sure how easy it is to replace from below. If you can't find one in Sydney I can recommend several suppliers in Melbourne.
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
The first time I did a fuel pump on a Corvette, looked the situation over & pulled the right front tire & used long extensions. Have posted that tip many times. Esp. for A/C.
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,487
Likes: 1
From: Sydney
Thanks for the tip Ganey.
Dath, thanks for your offer dude...but yeah, shipping might cost me a bit to Australia! it was a very nice gesture and I appreciate it.
RHD- thanks for your help. You know, I emailed AC Delco yesterday but they still havent replied. So I will give a few places a call today and see what I come up with.
My vette is meant to be going into a show this weekend...and I have a tight schedule this week with work.
I don't know whether it is safe enough to drive to my mechanic to fix? although I would like to fix it myself
so I will have to see what my bf thinks.
Will let you know how it goes. What a bummer! if its not one thing its another.
Dath, thanks for your offer dude...but yeah, shipping might cost me a bit to Australia! it was a very nice gesture and I appreciate it.
RHD- thanks for your help. You know, I emailed AC Delco yesterday but they still havent replied. So I will give a few places a call today and see what I come up with.
My vette is meant to be going into a show this weekend...and I have a tight schedule this week with work.
I don't know whether it is safe enough to drive to my mechanic to fix? although I would like to fix it myself
so I will have to see what my bf thinks.Will let you know how it goes. What a bummer! if its not one thing its another.
Burning Brakes
Joined: Jan 2004
Posts: 1,043
Likes: 4
From: Va
i recommend a Carter Pump
not the edelbrock or holley style, I had the edelbrock and fuel pressure was all over the place, sometimes 4 lbs. psi, sometimes 9 lbs. psi.
Not sure about the AC Delco pump.
Replace the hoses and clamps while you are at it.
Hope you get it to the show this weekend
Not sure about the AC Delco pump.
Replace the hoses and clamps while you are at it.
Hope you get it to the show this weekend
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
No problem, didn't notice you were over on the other side of the pond If you haven't ever replaced a pump, another recommendation in addition to what Ganey said (he is correct, makes it much easier) is to use a long bolt through the front of the engine to hold the fuel pump rod in place when you put the new pump on. There will be a bolt hole with a shorter bolt in it, just take the short one out and *GENTLY* put a longer one in once you have pushed the pump rod all the way up into the hole. It holds the rod in place nicely and keeps you from having to use one of half a dozen other tricks that all can be frustrating when there isn't much space to work in.
-dath
If you haven't ever replaced a pump, another recommendation in addition to what Ganey said (he is correct, makes it much easier) is to use a long bolt through the front of the engine to hold the fuel pump rod in place when you put the new pump on. There will be a bolt hole with a shorter bolt in it, just take the short one out and *GENTLY* put a longer one in once you have pushed the pump rod all the way up into the hole. It holds the rod in place nicely and keeps you from having to use one of half a dozen other tricks that all can be frustrating when there isn't much space to work in.-dath
Pro
Joined: Dec 2003
Posts: 642
Likes: 0
From: Dallas Texas
Easier than that is just to lube up with rod with some good grease and slide it up into place. The grease will hold the rod in place as you install the pump. Worked like a charm for me.
cosmic... swapping out the fuel pump is a piece of cake. You can have it done in 30 minutes in your garage.
cosmic... swapping out the fuel pump is a piece of cake. You can have it done in 30 minutes in your garage.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,487
Likes: 1
From: Sydney
thanks for the help dudes...I appreciate the tips. 
looks like Im going to tackle this one myself then
Regarding the LUBE tip....I don't know if I read it when searching through the forum archives..but does the LUBE get into/soak into places that it shouldn't?
not that I really care at this stage...Im happy to give it ago..armed with the advice from you guys!
looks like Im going to tackle this one myself then
Regarding the LUBE tip....I don't know if I read it when searching through the forum archives..but does the LUBE get into/soak into places that it shouldn't?
not that I really care at this stage...Im happy to give it ago..armed with the advice from you guys!
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
Greasing it won't hurt anything, but I had no luck with that technique myself. The damn thing would stick for a few seconds, then I'd just about get everything lined up and bam, out it would slide. The bolt really is the easiest way in my opinion. Some people also use a hacksaw blade to hold it up in place and then slide the blade out once the pump handle is holding the rod in place. Just too much messing around in a tight space IMHO.
-dath
-dath
