Starting problem - 10 pumps
Thread Starter
Safety Car
Joined: Feb 2006
Posts: 3,557
Likes: 0
From: Ridgeway VA
Starting problem - 10 pumps
I drive a 1970 every weekend. When first starting it takes about
10 pumps to get it started. After that it's fine all weekend. Just
had a tune-up, HEI added, etc. A "mechanic" said that fuel drops
down the line and that's why, after a week, it needs more pumping.
Has a Q-jet, mechanical fuel pump, been souped to about 400 hp,
takes off like a rocket (due to rear end ) and it's an automatic.
Idle is set at about 1100 and must shift into neutral at lights or
else brakes will wear out.
Any ideas, suggestions are welcome. Thanks!!!
10 pumps to get it started. After that it's fine all weekend. Just
had a tune-up, HEI added, etc. A "mechanic" said that fuel drops
down the line and that's why, after a week, it needs more pumping.
Has a Q-jet, mechanical fuel pump, been souped to about 400 hp,
takes off like a rocket (due to rear end ) and it's an automatic.
Idle is set at about 1100 and must shift into neutral at lights or
else brakes will wear out.
Any ideas, suggestions are welcome. Thanks!!!
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
Older Q-jets sometimes develop a fuel seep at the two little nipples on the bottom of the main body, where the secondary fuel flows. Remove the throttle body and cover these with epoxy next time you have it off. That may fix the problem. If the problem is bad, you may be able to smell gas on your dipstick. If this is the case, fix it right away. God bless, Sensei
Race Director
Joined: Sep 2002
Posts: 10,362
Likes: 5
From: San Diego - Deep Within The State of CONFUSION!
Yep 
They leak.
At the bottom of it, there's casting plugs. After a lotta years they leak, draining fuel out of the float bowl into the intake manifold as the car sits. Sometimes it leaks bad enough to where a car won't start the very next morning after being driven.
The reason you have to keep pumping the pedal, is because you are waiting for the fuel pressure to fill the float bowl so the accelerator pump can squirt. Save your energy! Don't keep pumping the pedal because there's no fuel in the carburetor until the engine cranks over a bit!
As stated, the cure for it is to epoxy these plugs at the bottom of the carb.
NOW ON TO YOUR NEXT STATEMENT:
You said your brakes fail at a stop unless you put it into neutral? Get your master cylinder checked and get the brake system checked for pressure leaks. this, assuming that your remark was referring to the pedal fading to the floor as you sit at the light.
They leak.At the bottom of it, there's casting plugs. After a lotta years they leak, draining fuel out of the float bowl into the intake manifold as the car sits. Sometimes it leaks bad enough to where a car won't start the very next morning after being driven.
The reason you have to keep pumping the pedal, is because you are waiting for the fuel pressure to fill the float bowl so the accelerator pump can squirt. Save your energy! Don't keep pumping the pedal because there's no fuel in the carburetor until the engine cranks over a bit!
As stated, the cure for it is to epoxy these plugs at the bottom of the carb.
NOW ON TO YOUR NEXT STATEMENT:
You said your brakes fail at a stop unless you put it into neutral? Get your master cylinder checked and get the brake system checked for pressure leaks. this, assuming that your remark was referring to the pedal fading to the floor as you sit at the light.
Thread Starter
Safety Car
Joined: Feb 2006
Posts: 3,557
Likes: 0
From: Ridgeway VA
Thank you for the input and I shall look into. When I said I have
to shift into neutral at lights -rather than hold the brakes (the brakes
work fine) it idles at 1100 because of a large cam, etc - I can go
20-25 mpm just in third gear without accelerating.
to shift into neutral at lights -rather than hold the brakes (the brakes
work fine) it idles at 1100 because of a large cam, etc - I can go
20-25 mpm just in third gear without accelerating.
Le Mans Master
Joined: Oct 2005
Posts: 9,429
Likes: 44
From: Macon, GA
Originally Posted by PETKAH
Thank you for the input and I shall look into. When I said I have
to shift into neutral at lights -rather than hold the brakes (the brakes
work fine) it idles at 1100 because of a large cam, etc - I can go
20-25 mpm just in third gear without accelerating.
to shift into neutral at lights -rather than hold the brakes (the brakes
work fine) it idles at 1100 because of a large cam, etc - I can go
20-25 mpm just in third gear without accelerating.
Thread Starter
Safety Car
Joined: Feb 2006
Posts: 3,557
Likes: 0
From: Ridgeway VA
sperkins - perhaps you are suggesting I'm kidding? No, I'm not - it is
an automatic with a souped up engine, idles at about 1100 - if I apply
brakes at light it will sputter and die -therefore neutral. Two mechanics
tell me it's about 400 hp and has a clutch or dragster rear end.
I'm not an expert. Just the truth.
an automatic with a souped up engine, idles at about 1100 - if I apply
brakes at light it will sputter and die -therefore neutral. Two mechanics
tell me it's about 400 hp and has a clutch or dragster rear end.
I'm not an expert. Just the truth.
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Melting Slicks
Joined: Feb 2003
Posts: 2,330
Likes: 6
From: Long Island NY
I wonder, I had the carb professionally rebuilt (I wish LARS did it) and it takes 10 pumps, and then it's Ok as stated earlier. I look under the carb and it looks like they glued the bottom wicks... I have a new fuel pump, can it be something else...
