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Fuel issue

  • Thread starter Thread starter STSFCTN67
  • Start date Start date Jun 29, 2008
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Jun 29, 2008
#1
  • Jun 29, 2008
  • #1
I finally got the Mustang back on the road and now I have a fuel issue.
Plenty of gas
Edbrock carb and Carter fuel pump.
No trash in the tank.

Tell me if I have already solved the issue just now writing this question.

The car will drive fine for a short while then the fuel line to the carb, see through filter, will just run bone dry. I would let it sit for a while and I will have to turn it over for a while then it will run for a block or so then die again. I noticed when the tank was almost empty it ran further before dieing on me. And when going up hill it would almost instantly die.

The only thing I changed since the paint job was a flip open gas cap. I wanted it so I could keep the gas from pouring all over the back of the car with hard accelleration. The inner cap with the rubber gasket says that it is vented. So with the car stuck on the street, I opened the cap and heard the air going in, turned the car over and it started. Now I am hesitat to drive it around to test my theory without a towstrap ready.
Am I right or should I check the fuel pump. If I am right how do you check to make sure the cap really is vented?
 

jcode68

Active Member
Jul 15, 2003
892
1
29
Massachussetts
Jun 29, 2008
#2
  • Jun 29, 2008
  • #2
Sounds like the same problem my friend had with his 67 when he first got it. He drilled a small hole in the cap and problem has never come back. As far as your cap being vented, not sure how you can tell, I had asked that question here and never got an answer to that part of the post. The top of my friends gas tank was actually collapsed from the pressure created from the lack of venting. If yours has this symptom, I would feel pretty certain this is your problem.
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Jun 29, 2008
#3
  • Jun 29, 2008
  • #3
OK
that was not it. Got stranded again. When it started to stall out when going uphill I immediately pulled over and the filter was full. It would not start but I did bring some starter fluid and I feathered the gas to get home. I am going to check the fuel filter next.
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Jul 1, 2008
#4
  • Jul 1, 2008
  • #4
Fuel filter is fine.
The car runs great in the garage but dies when going uphill. It has to be carb related.
Does anyone have any idea where I should look when I pull the top off the edelbrock carb? I am assuming the float is stuck but and look for any trash but has anyone else had this issue?
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Jul 6, 2008
#5
  • Jul 6, 2008
  • #5
Still having the same issue, the car will not drive uphill. I took the top off the edelbrock carb and the floats were in spec. I cleaned the fuel fliter. The fuel pump is fine. It runs great on flat ground.

Basically when going uphill it starts to starve for gas and will die unless I quickly turn around.

Are there any other ideas???????????????????????
I still think it is carb related but what else can I check?
 
M

mustangman1974

Member
Jan 17, 2004
463
0
16
Jul 6, 2008
#6
  • Jul 6, 2008
  • #6
pickup in gas tank is bad. drain the tank and take our the fuel sending unit/pickup and look at the sock. I bet its deteriorated enough that it gets sucked closed going up hill.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Jul 7, 2008
#7
  • Jul 7, 2008
  • #7
Based on your initial post, your tank is not vented. Install a tank vent and your troubles will go away. Best way to run a vent is to run it from the tank up to the air cleaner. That way any fumes created from expansion will be consumed in the engine when you fire it up.
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Jul 7, 2008
#8
  • Jul 7, 2008
  • #8
Still no go

The gas cap is vented so I now think it just will not perform under a load. I drove uphill without the cap and it did the same thing.
The sending unit is less than a year old and before I stopped driving the car to paint it, there were no issues.

I can leave my neighborhood and drive on flat ground fine; but as soon as I try to go uphill it will bog.

I tried to leave the driveway and then go immediatly up the hill and it will die. It is either fuel starvation or electrical starvation.

I had the fuel line off the carb and the hose into a 2litre and turned the key and it pumped fine. I will recheck the plugs to see if they are still snug since I recently changed the plugs. \

Is there a better way to check the fuel pump? Is there a better way to check the engine under a load?
 
M

mustangman1974

Member
Jan 17, 2004
463
0
16
Jul 9, 2008
#9
  • Jul 9, 2008
  • #9
check to see if you neutral start switch wires are touching your exhaust. I have that happen, but my car would start.

Electrical starvation is easy install a tach if it stops working when you stall its electrical. If its fuel the tach will slowly stop when the car comes to a stop. At least thats how my mallory tach works when I run out of gas.
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Jul 9, 2008
#10
  • Jul 9, 2008
  • #10
Now I really need help

So the wife's car died today with what I am thinking is a bad alternator and we are now sharing just my truck. It would be great if we could figure out this problem with the mustang so I can drive it while I figure out the minivan's issues.

I checked all the plug wires and I will check the old nuetral safety wire which is now my kill switch to make sure it is not touching anything when going uphill.

Is there a way to check fuel pressure without a pressure gauge?
 
M

mustangman1974

Member
Jan 17, 2004
463
0
16
Jul 10, 2008
#11
  • Jul 10, 2008
  • #11
when you checked the float you checked for both ranges for open and close. My edlebrock manual show both measurements. U need to test it under a load on level ground to eliminate the angle issue. I n one of your post you said you had to feather the carb to get it home, which would mean its a fuel issue. How steep is that hill? to steep would drain the bowls if the floats were off by a bit. You may also want to check to see is the floats float. If they don't the carb may have to much fuel and running extra rich. The car could then be major flooding under a load condition when the metering rods go to power the extra fuel may kill the spark and flood the engine. Yeah its rare but those darn brass floats do leak on occasion.
 
S

STSFCTN67

Member
Feb 5, 2003
450
0
16
Denver, CO
Aug 3, 2008
#12
  • Aug 3, 2008
  • #12
Figured it out

I finally figured out the fuel issue that I have been having. The carb was not getting gas. I checked the fuel pump and it was fine. I cked the fuel line past the filter that was clean and it stopped flowing - the fuel filter was on backwards. It only flows one way.

I drove it up that hill and it just charged on up. I drove it around for about 15 minutes with no problem. The tremp gauge was perfectly vertical. I got it back in the garge and kept it running to check everything out and I saw gas boiling through the glass filter from the fuel pump to the carb.

It sounds like I still need to either get an electric fuel pump or figure out why it is running so hot??
 
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