HELP" no power under load.
Thread Starter
Heel & Toe
Joined: Dec 2007
Posts: 19
Likes: 0
From: Coal City IL
HELP" no power under load.
no power under load.well i just bought this car . i was told the motor was rebuilt it has signs of that . a new carb a MSD distributor not a HEI set up . the problem is when your driving under 40mph its runs great but if you romp on it it falls on its face some times you can get it to 50MPH but most of the time you cant get it over 40 mph im not sure were to start ????any help
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Carb and distributor are the first places to start. Set timing according to Barry's sticky at the top of the page. You are close by. I live in Millington. Welcome to the forum!
Melting Slicks
Joined: May 2006
Posts: 2,369
Likes: 103
From: Centerville Louisiana
Just what Mako said first thing comes to mind is your distributor being 180 deg. off being it ppears to be a new install
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
I had the same problem on my 79 it ran fine as long as I didn't step on it, once I stepped on it it fell flat. It turned out to be the fuel sock in the tank, if its gunk up you won't get good fuel flow from the tank to the pump. I replaced it and problem solved.
Melting Slicks
Joined: May 2006
Posts: 2,369
Likes: 103
From: Centerville Louisiana
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Thread Starter
Heel & Toe
Joined: Dec 2007
Posts: 19
Likes: 0
From: Coal City IL
well i have changed the fuel pump and felter at the carb . the coil which was a msd coil and the dist is a mallory . i did replace the coil with a stock one. the problem has changed it really dont want to run now. im thinking of changing the dist with a hei set up and vacume adv because the one i have in the car has no vacume adv what do yous think IM ALL
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
When you had the fuel pump off, did gas run freely through the line from the tank? If not, it could be the sock problem in the tank.
If you are getting gas to the carb you should see it squirt into the primaries moving the trottle by hand.
Do you have spark at the plugs? Pull off a wire and hold it near the plug while someone cranks the engine.
If you have gas and spark, then it is timing. See the sticky thread at the top of this forum section.
If you are getting gas to the carb you should see it squirt into the primaries moving the trottle by hand.
Do you have spark at the plugs? Pull off a wire and hold it near the plug while someone cranks the engine.
If you have gas and spark, then it is timing. See the sticky thread at the top of this forum section.
Instructor
Joined: Feb 2007
Posts: 190
Likes: 0
From: shrewsbury Pa.
well i have changed the fuel pump and felter at the carb . the coil which was a msd coil and the dist is a mallory . i did replace the coil with a stock one. the problem has changed it really dont want to run now. im thinking of changing the dist with a hei set up and vacume adv because the one i have in the car has no vacume adv what do yous think IM ALL
Thread Starter
Heel & Toe
Joined: Dec 2007
Posts: 19
Likes: 0
From: Coal City IL
When you had the fuel pump off, did gas run freely through the line from the tank? If not, it could be the sock problem in the tank.
If you are getting gas to the carb you should see it squirt into the primaries moving the trottle by hand.
Do you have spark at the plugs? Pull off a wire and hold it near the plug while someone cranks the engine.
If you have gas and spark, then it is timing. See the sticky thread at the top of this forum section.
If you are getting gas to the carb you should see it squirt into the primaries moving the trottle by hand.
Do you have spark at the plugs? Pull off a wire and hold it near the plug while someone cranks the engine.
If you have gas and spark, then it is timing. See the sticky thread at the top of this forum section.
Instructor
Joined: Mar 2007
Posts: 223
Likes: 0
From: Henryville Indiana
We had one do that at the restoration shop I used to be lead tech at.71-350,no power on full throttle.We replaced coil,fuel pump,filter,it had a new fuel tank and unit.
Found it to be a leaking main well inside the Q jet.Put on another Q jet and it ran like a raped ape to 100+mph!!!!!
Found it to be a leaking main well inside the Q jet.Put on another Q jet and it ran like a raped ape to 100+mph!!!!!
Intermediate
Joined: Jun 2007
Posts: 49
Likes: 0
From: Cameron Park CA
Check the fuel sock. On my 79 I was able to get it up to 60mph and as soon as I would try and step on it it would fall flat So I replace plugs,wires, coil,cap,rotor, adv. can and set timing, didn't fix it. Replaced fuel pump, line and filter in carb and rebuilt the carb, didn't fix it. Replaced the HEI distributor with a new one still didn't fix it and it kept getting worse. It got to the point where the car wouldn't even make it down the street it would fall flat every time I pushed the gas. so after all that I finally pulled the fuel sock and it was so gunk up I pulled it and ran another inline filter before the carb and left the sock off and solved the problem. The car runs great now. I wish I would have checked the sock first I would have saved myself a lot of time,money and frustration.
Instructor
Joined: Feb 2007
Posts: 190
Likes: 0
From: shrewsbury Pa.
Check the fuel sock. On my 79 I was able to get it up to 60mph and as soon as I would try and step on it it would fall flat So I replace plugs,wires, coil,cap,rotor, adv. can and set timing, didn't fix it. Replaced fuel pump, line and filter in carb and rebuilt the carb, didn't fix it. Replaced the HEI distributor with a new one still didn't fix it and it kept getting worse. It got to the point where the car wouldn't even make it down the street it would fall flat every time I pushed the gas. so after all that I finally pulled the fuel sock and it was so gunk up I pulled it and ran another inline filter before the carb and left the sock off and solved the problem. The car runs great now. I wish I would have checked the sock first I would have saved myself a lot of time,money and frustration.
I absolutly agree. Krugs2 seems to be Determined to have this be an Ignition prob. Hopefully he'll see the expence that you incurred trying to find the ignition fix,only to find that this is GOING TO BE fuel related. Please krug2, pursue the fuel fix as many here have suggested.
Thread Starter
Heel & Toe
Joined: Dec 2007
Posts: 19
Likes: 0
From: Coal City IL
well i jump to putting a hei dist on it and she will run no more problem run like she should . now its only been on day put i got her pass 70mph which i wasn't able to since i bought it so . but she really had me
Advanced
Joined: Jul 2007
Posts: 52
Likes: 0
Hmmm,....a plugged cat/verter will act like that too.
I got a free car once. The person told me that if I could drive it away, I could have it. Cut the cat out, fired it up and drove away. A '76 hatch back Dodge.
Before removing the cat, it would barely run above an idle.
I got a free car once. The person told me that if I could drive it away, I could have it. Cut the cat out, fired it up and drove away. A '76 hatch back Dodge.
Before removing the cat, it would barely run above an idle.