Ive got a ford 250 that I'm tired of. The car was parked a few years before being brought back into service. The carb was rebuilt and the car driven about 200 miles before it started loosing power to the point that the car will not run. I have gone through the common items to try to find the problem and at this point feel pretty defeated. Reman carb, full tune up (plugs, wires, cap, rotor, points, condensor, coil) got the car running good for roughly 10 miles and now it will not run. I did a compression check and all numbers looked good. Checked fuel tank and lines and installed a clear fuel filter to verify clean fuel getting to carb. Swapped 2 more reman carbs and finally re-rebuilt the original carb. I checked to verify good spark, distributor has not been moved and I can't imagine that timing would be too far off after swapping points and condensor that the car would not run. What am I overlooking?
get one of those spark plug testers you put between the plug and the wire and see if the spark is continuous or if it breaks up or stops , could be a failing coil or a condensor if it s not electronic ignition , if the later could be a bad ignition box or very worn distributor ?
My first thought was exhaust/muffler crumbling, but I’d think the compression test would be low if that were the issue? The old saying “if it can’t get out, it can’t get in”. So if you have “good compression” let’s you know rings and valves are adequately sealing, you’ve put enough carbs on it to feel good that’s not an issue. At this point I’d agree above about checking out the ignition, but also the fuel delivery to the carb. Not a lot left
What he said.^^^^ Easy to loosen the exhaust system at the manifold. Rodents could have blocked the exhaust system when it was parked.
Valves to tight ? Vacuum leak Plugged exhaust Timing chain stretched shitty tune up parts ? Condenser/ coil / points ? Wiring to something ? Mouse or something died in the intake ?
You say the distributor has not been moved, have you tried adjusting it? Advance/retard? What was the condition of the inside? Advance working? Weights free to move? Plate seized/ springs rotted off, wobbly shaft? Be sure to verify the exhaust is not plugged, make sure the engine is properly grounded. When it was brought back into service, what was the condition of the drained oil?
I would check for a plugged muffler and crimped exhaust pipes. These things will allow the engine to run a short time and stop when exhaust back pressure becomes to much to handle. The muffler would be the most likely candidate as loose/rust damaged baffles can move into a position to plug the thing. If a catalytic converter is in the system and is plugged it will give the same symptoms.
Thanks for the suggestions to look at. One thing I did not mention is that the exhaust has been completely replaced, so internal deterioration is not a concern. I'll be checking the movement of the distributor advance as well as checking to make sure the timing has not jumped a tooth.
Did you check to see if someone had crawled up in there and built a nest.... Can/does happen...... LynnW
If it has good compression, good spark and fuel it will run. Unless, they aren't getting there at the proper time. Could it have jumped time (timing gear and/or chain)? If it has, advancing the distributor timing may get it to run but you still have to fix the problem.
Have you bumped it over on compression on number 1 to check and see if it is in time? I bought my daughter a 68 Monarch with one of those in it because it wouldn't run well enough to pull a sick whore off the pot, Took it for a short test drive, got out to check it over about a half mile from where the people had it opened the hood and looked around and happened to go to wiggle the air cleaner or top of the carb and the body of the carb was loose from the base. We bought it, took it home and pulled the carb and tightened the screws and put it back together and my daughter drove it to town soon after. Great tougher than an old boot kids car.
Vacuum Leak... Fords are sensitive to vacuum leaks. I guess they all are.... Anyway make sure that all the gaskets/ hoses/vacuum lines are connected and good. Make sure nothing is left unhooked. Distributor.... I've gone through this with a Ford. If the distributor is worn, it will have a "wandering zero". It will not stay in time. It's maddening! Ford continued with the Load-O-Matic distributors for the small sixes until Duraspark. A LOM distributor and the factory single carburetor are matched pairs and it will not advance properly without a single LOM compatible carburetor. It should run but...It will not advance properly.
Have you changed the advance springs and weights inside the distributor? The springs soften up over time and can cause some weird issues. just trying to see things that you haven’t tried yet
The fact that the thing will run awhile before stopping does not indicate, to me anyway, a problem with ignition or timing. If that were the problem it would either run like crap or not at all. Have you blown out the gas line (toward the tank?). If it's been sitting for a long time, rotten gas can make all kinds of crap in the line, especially at the pickup screen in the tank. at the If there are any flexible gas hoses they can deteriorate inside and cause the problem you have especially with ethanol fuels and/or rotten gas. They can swell up inside and stop the flow, especially on the suction side. It's a fairly common problem. I would replace any flexible fuel hoses as a matter of routine. Keep us posted..
After running and rerunning everything down, it seems the culprit has been tracked to some broken/faulty plugs. I've replaced the pricier NGKs with elcheapo Autolites. Gapped the new plugs and installed, fired the car up and its running pretty smooth. Sometimes it's better to start over from the beginning and run down every possibility.
Always start with the simplest stuff, eh? I know NGKs are popular but I've never had good luck with them. Autolites are just fine.
The Jalopy Journal
