C1 1960 lousy acceleration

[Jim Sloan]

Here's the problem. All of a sudden I seem to have a "miss" or something when I accelerate from a stop. The engine seems to lug badly under load until the car reaches about 20 MPH. When you are driving at 30 or above it seems fine.
The car starts fine every time, the choke is working fine, it idles fine and it shuts right off. When you rev the engine it seems fine too. It is just when you put a load on it when you start off it really seems to lug and chug. What should I be inspecting for a problem and in what order??? The things that come to my mind as possibilities are: Carb, fuel filter, spark plug wires???
By the way, the plugs are new (AC R45S). It is the single carb 283 engine in my 60.

Thanks in advance for any help!

[Randy G.]

Re: C1 1960 lousy acceleration

Check the vacuum advance.

[Jim Sloan]

Re: C1 1960 lousy acceleration

How and what would I be checking for?

[Joe C.]

Re: C1 1960 lousy acceleration

Jim,

Make sure the dwell is 30 degrees. If the plug wires are old, replace them, and make sure that both ends are fully seated. Check the inside of the cap for carbon.....clean and/or replace. Swap in a known good coil......sometimes a weak ciol will cause misfiring under load.

Joe

[Mike McKown]

I think I'd do a plug check

Accelerate the car from a dead stop and hold your foot in it as long as it is missing. If/when it clears out, kill the engine immediately and shove in the clutch. When the engine cools, pull the plugs and read them. You may be able to identify which if any cylinder is the culprit in case of an ignition miss and will localize your search.

[Roy B.]

Re: C1 1960 lousy acceleration

Randy could be right, take a hose connect to the V.A blow in it , if you get no resistance it's no good.

[Randy G.]

Re: C1 1960 lousy acceleration

Roy:

This was his question"

"Here's the problem. All of a sudden I seem to have a "miss" or something when I accelerate from a stop. The engine seems to lug badly under load until the car reaches about 20 MPH. When you are driving at 30 or above it seems fine."

By his description, something has failed or moved. "All of the sudden" and "lug badly under load" are key. It's sounds timing related. A simple check would be to do this:

First, check the timing with a timing light to make sure it's right. If it's wrong, fix it. Since the problem "All of the sudden" happened make sure the distributor hold-down bolt wasn't loose allowing the distributor to move.

Then, with the engine at idle, vacuum line connected to the vacuum advance on the distributor, transmission in neutral or park, brake on etc., have someone snap the throttle open and immediately let off while watching the timing mark with the timimg light to see if it moves. Be very carefull under the hood with loose tools. It should be obvious if the advance works by watching the timing mark advance and retard from the idle setting.

If the timing mark didn't immediatley move, or it wasn't clear to you what it did, remove the distributor shielding if you have it on your car, then check the vaccum advance like Roy said. I would remove the distributor cap and make sure the points plate freely rotates with the advance unit. If you happen to have a distributor with centrifical advance make sure the springs are in place and the unit moves freely, too.

While your at it you should check the dwell, the condition of the cap, rotor, points, wires, cleanliness of the assembly under the cap. Look for carbon tracing, evidence of moisture or contamination by ANY means (water, dirt, oil, etc., in and around the cap/rotor/points/wires. Electrical parts spray cleaner can be bought at any major chain auto parts store to clean up the assembly...protect your paint and plastic before you spray).

Look at the rotor where it contacts the cap in the center and the tip. Scotchbrite or fine sandpaper can bring it back to life. Look inside the cap for carbon tracing, cracks, look at the center terminal where the rotor makes contact and make sure it's in good condition and, again, look for contamination.

Most of this is just general maintenance that costs you nothing but the time to do it. Early acceleration requires a timing change. If it's not getting it, it will do exactly as you describe.

Let us know what you find.

[Jim Sloan]

Re: C1 1960 lousy acceleration

The mystery problem has been solved!! As per your suggestions, I checked the timing, checked the vacume advance, checked all inside the distributor cap, and everything checked out OK. I test drove the car again and the problem was still there. So as one of you suggested, I installed a new set of spark plug wires. I put the new ones in, test drove the car, and presto! Problem gone. All of the described symptoms were gone and the car drove like a dream. I guess something must have happened with the wires when I recently changed the plugs. I had visually inspected the wires for condition when I put the new plugs in and saw nothing wrong at the time. I had even double checked to make sure that the connections were good also. So I guess it goes to show you that just because it looks OK doesn't mean it is.

Thanks to all of you for all of the help in solving this problem for me just in time to take the car to the Goodguys Pacific Northwest Nationals in Puyallup, Washington.

[Randy G.]

Re: C1 1960 lousy acceleration

Great job!