Thread: engine has no power/torqe

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i did buy a chevy 57 with a 307 instaled by a previous owner. it has a 3 speed manual with overdrive. the engine seams to have no torqe/power


everything on the ignition side is new, i did replace the carb with a 650 holley, new fuelpump ,new fuel line and the pickup line in the tank.(it seamd like it did not get enough gas to me) the compession seams ok ,(150 high, 135 low)i have checked timingchain and markings, verified tdc it runs great on idle, and revs up fine but as soon as you put it in gear and tryes to drive it stops unless you rev it up really high and as soon as you let go of the gas it hesitates and stops . im running out of things to do

Welcome to CHR!! Glad to have you here, and hope we can help get the 307 pulling a little better. What is your ignition system? Unfortunately, "new" doesn't guarantee "good" in today's world market, especially in the arena of spark plugs. Run through the ignition components that you have in place and let's see if anything jumps out.

Is the 650 NEW? It dose sound like fuel problem, did you check fuel pressure? 5/6 #

thanks for your reply

the distriputor is what came with the engine .seams fine. i cleand it made sure the counter weights moves.
new points.capacitor.rotot.cap.spark plugwires .sparkplugs. the ignition coil is a uesd one that worked fine on anather car, most parts bought at napa. i did use a vacum gage to check the enginge and is is in the green.

If you're confident about the dwell on the points and quality of the other components I'd probably verify the fuel system like Charlie says. You say you put in a new fuel line and pickup line in the tank. Had the car been running OK before, or had it been idle for a time? I'm thinking crud in the tank could be plugging the "sock" filter, or that either an in-line fuel filter or even the screen at the carb inlet could be partially plugged, blocking flow?

Are you CERTAIN the coil is installed correctly? It will run with it installed backwards and act like your symptoms suggest.

The "+" side should be from the key switch, the "-" side goes to the coil. And for testing purposes, if a condenser is on the coil connections, leave it off.

And welcome to the "Club"! Maybe once you've settled in you'll share a pic or two??

Originally Posted by 34_40

Are you CERTAIN the coil is installed correctly? It will run with it installed backwards and act like your symptoms suggest.

The "+" side should be from the key switch, the "-" side goes to the coil. And for testing purposes, if a condenser is on the coil connections, leave it off.

And welcome to the "Club"! Maybe once you've settled in you'll share a pic or two??

I think Mike meant to say, "...the "-" side goes from the coil to the distributor" just to clarify. Please report back what works for you.

YES! Thanks!..

Originally Posted by rspears

I think Mike meant to say, "...the "-" side goes from the coil to the distributor" just to clarify. Please report back what works for you.

Now I'm really concerned---I understood what Mike meant!!!!!!

Originally Posted by Dave Severson

Now I'm really concerned---I understood what Mike meant!!!!!!

Now wait a minute, he was talking about maybe having the coil wired backwards, and said the "+" comes from the key, and the "-" goes to the distributor They BOTH go to the distributor!! One to + and one to - !! The question is "Where is the orher one FROM!!

Leave it to Roger to complicate matters!
Let's try it this way.

Have you set the floats in the carb????

Originally Posted by rspears

Now wait a minute, he was talking about maybe having the coil wired backwards, and said the "+" comes from the key, and the "-" goes to the distributor They BOTH go to the distributor!! One to + and one to - !! The question is "Where is the orher one FROM!!

Correct!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

when i got the car it had a rochester 2 barell on it and it what defenitly starved on fuel at that time the inlet filter whas pluged .so i cleand that, and the hole carp for that matter. dident help, changed the fuel pump, dident help. replaced the carp with a used holley 650, witch i did rebuild . still no good so i replaced all the fuel lines, this made a huge inprovment on the fuel delivery. so i thought i hade fixed it, now the fuel filter is copmletly full(you could noly see a small amount of fuel going through it before)it idels great so i checked the float levels needed some adjustment used a vacum guage to adjust the mixer screws

the last thing i did whas to take a coil from anather car wierd it strait from the bat via a toggle switch to the + on the coil , the other side to the distributor it still whas acting the same but i need to try it a bit more

You have a polluted fuel tank, either sediment or rust or both. Until you either 1) drop the tank and thoroughly clean it or 2) replace the tank with a new one you will continue to have problems. The original fuel lines were plugged, you replaced them and now you're plugging the filter. Clean out your tank, or easier, buy a new one.