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EFV-8 Club Forum / General Ford Discussion / Polarity check

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Posted By Discussion Topic: Polarity check -- page: 1 2     flatcreeker 12-13-2021 @ 7:50 AM reply profile send p.m. Member Posts: 48 Joined: Feb 2021 Tom- I am making a list, a rather long list, of things to ck when I get back to the cabin (and Merc) including the items in your last post. I am sending you a PM on a different matter. Thanks again, Doug TomO 12-13-2021 @ 7:22 AM reply profile send p.m. Senior Posts: 7252 Joined: Oct 2009 Doug, if there is a vacuum leak in the carburetor, it may only show up as the carburetor warms up. You can check for this by spraying carb cleaner around the base of the carburetor. Pay particular attention to the area where the carburetor body meets the cast iron base. Another area of concern is around the throttle shaft. Concerning the gas odor, you should try to isolate where the odor is coming from. I never get a gasoline odor inside or outside of my 40 Mercury. If the odor is only inside of the car, check the fuel sending unit area to make sure that gas is not leaking there. You may also have rust pinholes in the top of the tank. You should also check the condition of the rubber hose that connects the filler pipe to the tank. I get about 10 years of service from them. A bad distributor rotor can cause a miss like you described, but it usually shows up at a steady speed as well as when accelerating. The fix is to wrap 6the distributor shaft,under the rotor, with shrink tubing or electrical tape. Have you contacted any of the Regional Groups near you? You may be able to get some help from one of the members. Tom flatcreeker 12-12-2021 @ 9:46 AM reply profile send p.m. Member Posts: 48 Joined: Feb 2021 Greetings Tom, Why might the pump and or carb exhibit these symptoms only after running for 15 to 25 miles in ambient temps as low a 50F? The surface temps around the carb base and pump base register a max of 150F on my IR gun when I return from a trip to town of about 35 miles. Unsure of the significance but when I get in the Merc after it has sat for a few days, there's a noticeable gasoline odor. There is not what I would consider a significant odor of gas under the hood at such times, nor anywhere around the outside of the car. Doug TomO 12-09-2021 @ 8:45 AM reply profile send p.m. Senior Posts: 7252 Joined: Oct 2009 Missing that occurs only when accelerating is usually carburetor related. It could be a vacuum leak, bad power valve, float level or fuel starvation. Charley Schwendler in New York seem to do the best job of rebuilding carburetors for these cars. To check fuel delivery, you need a graduated 16 ounce or larger container to determine the amount of fuel delivered in a measured time. Disconnect the fuel pump line from the carburetor and direct it into a graduated container. Crank the engine long enough to get 2 ounces of gas in the container and then continue cranking for 15 more strokes of the pump. The pump should have delivered 6 more ounces of gas. Insufficient fuel delivery can be caused by a vacuum leak, plugged flex line, worn pivot in the pump arm, stretched diaphragm, plugged fuel line or tank pickup, plugged tank vent or wrong gas cap or a worn push rod. The push rod should be 8 7/8" long for the cast iron manifolds and 7 7/8" for the aluminum manifolds. It travel is about 3/8". Tom flatcreeker 12-08-2021 @ 6:27 AM reply profile send p.m. Member Posts: 48 Joined: Feb 2021 The problem first occurred while on a 75 mile drive after about 40 miles. This, after about 1,100 miles of smooth running since I received the Merc. The problem only occurs under acceleration. There is no fading or sputtering like I associate with fuel starvation but a sudden snap-stutter, repeating every second of so until I stop accelerating, without regularity likely because I stop accelerating.. I may be imagining it but once it starts, I sometimes believe I can "feel" some weakening of power just cruising along, not accelerating. It doesn't do the snap-stutter when parked and accelerating from idle. Before it starts, it runs like a lion. Once it starts, it seems to require less accelerating to initiate. I have tried the application of various amounts of choke when the stutter occurs. It sometimes seems to make a slight, temporary improvement but enriching the mixture doesn't resolve the problem. I have replaced the paper element filter (in-line between the pump and carb which I cut open for inspection and found clean), removed and cleaned the glass fuel bowl (which had a tiny amount of ultra fine black dust about the consistency of graphite in the bottom of the bowl) and inspected the screen, blew out the fuel line to the tank, and assured the fuel tank cap vent was open. I plan to eliminate the in-line fuel filter and install a steel line obtained from 3rd Gen. I plan to go over the fuel line as you suggested. There is bit of rubber fuel line with screw type clamps in the steel line near the tank where once was installed an electric pump. Will be away much of December so it may be a bit before I can return my attention to this cursed matter which stands between me and the road. I had hoped to move the Merc to Savannah for the winter but only if it's reliable as my wrench is here at the cabin. Thanks, TomO, for your continued counsel. TomO 12-07-2021 @ 2:41 PM reply profile send p.m. Senior Posts: 7252 Joined: Oct 2009 If I read your response correctly, your miss occurs when driving at a steady speed or when accelerating and only happens when the engine is at operating temperatures. You can try pulling out the choke a little (1/4 -1/2 way) to see if performance improves. If it does, your problem is fuel starvation. This can be caused by a weak fuel pump, vacuum leak in the flex line to the fuel pump,a vacuum leak in the line from the tank, plugged fuel line from the tank, plugged flex line or plugged fuel pick up in the tank. My first try would be to check the flex line, if it is hard and the outside is cracked, I would replace it. Next I would try to clear the line going back to the tank using compressed air. You can buy small cans of it at stores that sell computer products. If that worked, I would consider having the tank cleaned and sealed and replacing the line from the tank to the firewall. You can also check the spark when the engine is at operating temperatures. If the spark is good at idle, check it as you increase engine speed. If the spark is good, I would examine the inner caps for wear and for traces of cross firing. If these are OK, install your spare coil, distributor and condenser. Make sure that the bolt with the condenser grounding is tight. If that fixes your problem or changes the symptoms, send your current assembly to Skip for repair. Tom marko39 12-07-2021 @ 10:29 AM reply profile send p.m. Member Posts: 41 Joined: Sep 2016 Don't assume a condenser is good just because it's new. Especially nos. or nors. ones that are decades old. Have them tested to be sure. I tested about 10 nos. and Nors. And found most of them bad. flatcreeker 12-07-2021 @ 6:57 AM reply profile send p.m. Member Posts: 48 Joined: Feb 2021 Thanks 40Coupe. Didn't mean to throw a curve ball re the generator. I have no problems with the generator, I'm just trying to learn if I can (and if so how) use my device (since it indicate polarity when used) to determine generator polarity. I am electrically challenged but have this nice little instrument I want to exploit. 40 Coupe 12-07-2021 @ 5:26 AM reply profile send p.m. Senior Posts: 1675 Joined: Oct 2009 I do not believe you engine miss is from the generator. If you have just over 7V charge your good with electrical charging. Do check out the fuel pump and fuel lines especially the pump input flex line. Make sure there are no air leaks or pin holes in the fuel line. 37RAGTOPMAN 12-06-2021 @ 10:27 AM reply profile send p.m. Senior Posts: 1959 Joined: Oct 2009 missing in engine, did you clean the spark plug;s and what heat range ? seems to me it is a spark plug problem , or sticking valves, has the engine been rebuilt , new valve guides,? maybe fitted to tight,ok when cold, but with heat not so good block expands and tighten the valve so they do not more fast enough and case a stutter,? do you hear any noises , from the air cleaner or the tailpipes ? let us know, could use more information to dianois the problem my 2 cents 37Ragtopman ,Maine,

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