Hey all. I hope I couldn't find any definitive answers to my problem so here it goes. I just picked up a 62 T-Bird with a 390. When I bought it, the guy thought that the gas tank needed to be be boiled out and disconnected the fuel line to the tank and ran one from a 1 gallon tank to prove that it ran. I figured out that it was just alot of old bad gas that was in the tank and I blew some air into the fuel line and my buddy could feel it out the nozel. I put some fresh gas in there and it runs fine in park. It rev's high and responds well. The problem is when you put it in drive and you punch it, it dies. The only way to keep it from dying is to let off the gas when I feel it dying and it sounds good again. I never actually drove it when the fuel pump was feeding from the 1 gallon tank so I never had a chance to experience what I'm experiencing now. I was thinking carb rebuild but wouldn't it have trouble revving up in park if that was the case? Checked for a vac*** leak and couldn't find one . I was thinking the timing may be off but didn't have time to check it, but again wouldn't it have the same issue in park? Thanks in advance for any advice.
Sounds like fuel starvation to me, engine isn't getting enough gas to run under load. Here's where I'd start.. First, are you sure the tank was drained out fully and it's not full of **** still? Old gas can turn into this nasty goo, the new gas could be digging up all kinda of junk. If it were me, I'd properly flush the tank out, clean the fuel pump, new fuel filter and clean out the carb, any of them could be clogged. Check the fuel pump for flow, are you getting enough fuel out of it? The pump could have a bad diaphragm from sitting (Sounds like she's been sitting a while if the PO told you the tank needed to be boiled). Remember to translate anything the seller says. "Needs tune up" is a carb overhaul at least.
No it won't necessarily act the same in (N) as it does while under a load. Run in place and then try running pulling a wagon full of lead. The carb is as likely to be gunked up as the tank was.
Quite possible you have something sloshing around and plugging the pick up, and when parked the debris is sitting on the bottom of the tank. I would drop the tank and get it boiled. I'm a little leery of old tanks , as mine was rusted from the top down from leaves and other debris laying between the top of the tank and the trunk floor. Everything I could see of the tank looked fine, everthing I could not see was shot!!! The first time I filled it up was depressing to say the least.....
Did you let it warm up or is it cold after you first start it up? It could be a simple choke problem.
Engines act differently under load, like being in Drive, not park. Sounds like the fuel system is suspect. I would start by dropping the tank and looking for all the above noted crud and junk. Pulling that carb apart would be next. Spark plugs and wires would be a good thing to change as well, especially if it has sat for awhile. Couple years ago we had a bad miss, under load, in slim53's 'Bird. Tried everything, tune, carb, wires, tank, etc.... Ended up finding the screw holding the condensor down inside the distributor was loose. Tightened it up, ran perfect. Replaced it just to be sure.
Good advice from everyone...if the gas thing dosen't work you might take a look at the coil..I've seen em' run fine at normal speed...and break down at high RPM. Just a thought. Good luck Sonny _____________________________ LIFE'S A GAMBLE......LET EM' ROLL
See if you can temporarily add a fuel pressure gauge to the carb. If the pressure maintains at speed, it could be the float level being too low or the inlet not opening up far enough (also clogged filter at inlet). If the pressure drops, check for rubber lines spliced into the hard lines. If a gate is cut into the rubber, it can close the line when the flow gets over some point. I have also seen braided lines on the tank side of a pump **** air when old (rubber is failing). Oh, tape the fuel pressure gauge to the outside of the windshield or anywhere you can see it while driving, but not in the p***enger compartment. John
Sounds like a bad accelerator pump in the carb. The accelerator pump is there to squirt extra gas into the air flow of the venturi when the throttle is quickly opened. Without the extra squirt of gas there is a serious bog when the throttle is opened quickly. Get a carb kit and rebuild the carb. The Ford carb on that T-Bird should be easy to rebuild.
Id check to make sure you have good gas in it, then look at the fuel pump. After that the carb could use a rebuild and set it all back to factory specs. Then make sure the choke is working and the motor is warmed up before you punch it. Have you checked any of the tune up stuff? you could check the points and plug gap, timing and thats free.
this man speaks the truth. If it dies when you punch it, then obviously the engine hasn't started to rev high and **** the tank/line/sock/filter shut. This is a tune issue- because the fuel system doesn't respond that fast to a throttle stab. Since ignition is unlikely, and it has all the earmarks of a instant throttle enrichment problem, i'd suspect the accelerator pump as well. rebuild the carb first, then do a filter, then inspect the tank as a precautionary measure. rick
Boil the tank, flush the fuel line (or replace it) , replace the "tank sock", check the flow rate of the fuel pump, (or just replace it) and rebuild the carb. My 72 F100 sat for a cpl of years, and ran fine, except at idle. Rebuilt the carb, and that fixed it. 4TTRUK
Check the float bowl, for gunk, and make sure the float is adjusted right.. I have seen this happen more than once.. Maybe this was posted earlier in the thread. disregard if it was.. good luck.
When you say you "punch it", is that from a standing start or while at cruising speed? If it standing start, it's carb. If it is dying out at cruising speed when you punch it, it's the fuel pump and or the fuel filter. I'm leaning towards the fuel pump/filter if it catches up if you lift then it goes again for a while. SPark
A friend tuned an Olds once and it ran like gang busters when revved in the shop with the hood up. He would close the hood and start down the street, and everything was fine. Then he would floor it and it would slam you against the seatbacks before wheezing down to idle speed again. Limp back to the shop, recheck everything he'd done, and the scene would repeat. For 10-12 times. Turns out he hadn't put the top on the air filter yet, and the carb was ****ing the under-hood insulation down onto the filter case (and carb's mouth) when hood was closed and venturis wide open. At half-throttle, it would have run all day, not enough air flow to attract the insulation. When he would get back to the shop and raise the hood, the insulation had always lifted to normal. He worked at it all day before he figured it out.
Amazingly great advice from everyone. Especially those who recommended the accelerator pump swap. Turns out that's all it was. I'm tempted to just rebuild the whole carb since the rebuild kit was all of $14.00. Anyhow she's running like a champ now. Took it out on the road today for apparently the first time in 13 years. Can't understand for the life of me why someone will just park a perfectly good car and not give someone else a chance to keep it alive. Thanks again everyone, big help.
Glad it was only a dried out accelerator pump. On those engines, if it came with an anti-stall dashpot, those can cause it to die when you put it in gear. You may as well rebuild the whole thing since you have the kit and that's an easy carb to work on. Bob
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