Car keeps cutting off

  • Thread starter Thread starter Anonymous
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:evil: OK, heres the deal. I thought I fixed the problem[see prior posts in this chain]. Apparently not? We made it about 30 miles and were doing freeway speed the whole way (approx 65-70 mph). We hit an uphill grade and the motor suddenly felt like it had lost its power (slow or no acceleration at speed). It kept running, and we got home fine, just at slower speeds.
After running at the lower speed, on city streets for awhile, the motor started running fine again (plenty of power). It would restart immediately after being parked for lunch, and shopping, etc.
Prior to this trip I replaced the points and condensor and things were going very well (too well actually). Should I try replacing the coil? Or does this sound like something else?
Engine temp is fine, oil is ok too.
Will accept any and all sugestions.
Thanks!
 
Dave, the first thing I would do is check for a blown gasket. Check the water, oil and do a hot compression test. Rule out the calamities, then proceed. :wink: Maybe check your coil for continuity, and your leads for conformity in resistance.

Now, are you still on the original carb and distributor? You may have advance issues, or possibly the carb clogged (vacuum power valve perhaps) when fuel was flowing freely under a load situation.

You'll need a timing light and remote tacho for the next test. Also the Ford manual for the year of 200 your distributor belongs to. A helper is handy. Get the engine up to operating temp (my rule of thumb is when the upper hose is too hot to hang onto long), and check your ignition timing at the RPM steps in the manual. Typically, advance is specified in 500RPM steps up to 3500 or 4000 when it is deemed to have fully advanced. Write down your results and compare with the book. More than say 10% fluctuation from spec merits some discussion - post again!

If you have a mechanical advance distributor (68-up, I think), this will be with the vacuum advance hose plugged off, at the carb.

If all is within limits, the carb may well be the culprit. But don't touch it until you've ruled out the other stuff.

Hope this helps.

Adam.
 
As Adam, mentioned, it could be a timing / distributor issue. Is your distributor the original distributor, and is your carburetor the orignial? If so, the vacuum motor may have a leak and may not be giving you enough advance. Also if you have the 66 distributor with a non-stock carb, you likely do not have the spark control valve that allows some advance under lower vacuum conditions. The 66 distributor does not have centrifugal advance and operates under vacuum only. Under load, you may not have enough advance and the engine is sluggish. Retarded timing will also contribute to overheating problems that you mentioned having in a previous post.

The other simple thing that could be suspect may be a partially plugged fuel filter or fuel line that is unable to deliver enough fuel under higher demand.
 
As far as I know I am running the original carb (which has been rebuilt) and the original diz.
I'll get together with the mechanic at my work and have him help me out on testing the vacuum advance. :shock:
Thanks guys!
 
Hey, biker;
Me, too, 'bout bikes - roadracing since '74....

A bad INLET valve in a fuel pump will provide precisely this situation:
going up hills, particularly with less than 3/4 tankful of gas, it will siphon out the carb float bowl. Stopping or slowing down long enough will let the pressure slightly equalize, then the low discharge flow will fill the folat bowl back up. The symptoms are: climbing any hill makes lost power, steep hills kill the engine. Going downhill actually helps.

I bring this up because I got 2 in a row bad, one from Checkmate, then from Auto Zoo, before getting a good one from NAPA (bad week that was..). I sawed up both of the $10 ones to see what was wrong: one had a mis-staked inlet valve and the other was completely loose, not sealing at all. Brand new, too. :evil:

There are 2 other things that can cause similar symptoms:
1.) Plugged fuel filter.
2.) Plugged fuel inlet in the (rusty/dirty) gas tank. This last one can be tested if you can find a compressor: open the gas cap and pull off the fuel line from the tank, right at the pump. Blow compressed air back into the tank for a few seconds. This will clear the inlet filter. It will re-plug later if the problem seems fixed, though - cars that sit a lot get this symptom pretty often (like my camper and my '67 LTD Fastback). The real solution is to clean out the tank if this happens.
 
Okay folks, I found the culprit! It was a partially clogged fuel line. I guess some trash from the tank made it into the lines, and over time began to build up, eventually allowing only drops of fuel to pass at a time.

I replaced the lines, and she is purring like a kitten again.

Thanks for all of the tips and ideas. Even though none of the mentioned items was responsible, its a good feeling to have new parts anyways =)

Thanks again for all of the help!
 
I had a similar problem with mine where someone or something had pinched/dented the steel line running along the frame rail. Had to cut out a section and replace.
 
Dave - Let's see, recently changed points, condenser, etc. and it ran like a champ for a short while then lost power and started running poorly. :hmmm:

First thing I'd check is your point/dwell gap to make sure it didn't close up on you. If you didn't get the lock down screw tight enough, sometimes the gap will close up and cause the exact problem you describe.

Just a thought. 8)
 
Hey, '66 -
I agree with Big Red for troubleshooting: the open port(s) on the manifold block in pix #A and #B should be plugged for troubleshooting.

To fix it all up, though - here's my assessment of your pix:
Pix A and B: this is the manifold vacuum port. Lots of things get hooked up to this, and the extra holes need to be plugged. The rubber covers sometimes rot and fall off, creating a leak. This will let you run only until the choke opens, then it will be 'iffy' after it warms up.
Pix C: Vacuum canister - this 'stores' vacuum for your accessories, like the heater/AC controls inside the car. The little flaps that open for heat (or AC, if you have it) get controlled by vacuum from your heater control lever. This canister stores the vacuum so that when you're climbing a long hill and manifold vacuum is low, the flaps won't shift from "heat" to "defrost" or something similar as the vacuum runs out.
Pix D: This is your heat control valve for the heater core inside the car. Like I mentioned above, when you switch the heater control inside to HEAT, it opens this valve with a vacuum line from the heater control.
So, from C and D you can presume that those hoses coming from inside the firewall go to the vacuum canister nipple and the heater valve. If you get them backward, it won't work right, but it won't hurt anything, either.
Pix E: I suspect (from the angle of the hose) that the angled one goes to the above-mentioned heater valve, the other one to the vacuum canister.

By the way - that heater valve should be connected into the heater hose where it comes out of the block, by the thermostat. The other side of the valve should go to the heater core. Probably, right now (if your heater works), someone connected the hoses straight to the heater core. If your heater does not make heat, then someone's disconnected the whole thing, likely because it was leaking and they didn't want to try to replace the heater core - which is sort of a pain. I've bought more than one car where someone did just this, because they didn't want to be bothered, them froze all winter without it... :?

Hope this helps.
Merry Christmas!
 
Greetings All!
I took my Ranchero to the mechanic at my work and he told me the following:
1. Repair or replace the vaccuum advance on the distributor [the
little tube where the hose connects up spins in the housing]
2. Replace the "filter" that is directly connected to the carburetor.
The reason I have it in " " is because he is not sure if it is fine
matter filter or just a "funnel" type filter.
3. Install an "inline"filter between the fuel pump and the carb.
4. Test the continuity of the coil.

Also, I was perusing the Scott Drake catalog and I saw that there is a filter at the gas tank? :shock: Is this true? How difficult is it to replace it?
 
I almost forgot. He also asked me to ask you guys if there is supposed to be a ballast resistor between the battery and the coil. He said they are usually mounted on the firewall. I do not have one.
 
The ballast resistor in our cars is a pink wire between the ignition switch and the coil. You could try bypassing it, and using an external resistor, to see if that's the problem. :wink:
 
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