| parrish | -- 05-23-2010 @ 9:49 AM |
|
I just took delivery of a 50 coupe and the car starts fairly easily, but stumbles badly for about a minute or so and then suddenly smoothes out quickly! It then idles as nicely as anyone could want and very quiet! It seems this must be a fueling issue of some sort, but I can't imagine what???
|
|
| supereal | -- 05-23-2010 @ 10:20 AM |
|
I suspect you are right. Check the fuel level in the carb bowl, the delivery and rate of the fuel pump, and the presence of any filters between the tank and the pump. The engine smooths out when it develops enough speed to work the pump harder and refill the bowl. It may be that the pump was not "fuel-proof", if older, and the diaphragm and valves have been compromised. We are also seeing more partially clogged fuel lines, probably due to the high moisture content of the "new gas". When you disconnect the fuel line from the carb and place the end in a container and crank the engine, you should see a steady stream with good volume. Pressure testing doesn't always mean adequate quantity.
|
|
| parrish | -- 05-24-2010 @ 8:52 AM |
|
I had noted that the glass fuel bowl remained full so I mentally eliminated any gas line issue. The carb was tight and seemed fuel ready, so now the pump jumps into the spotlight...thanks for the input
|
|
| parrish | -- 05-24-2010 @ 8:52 AM |
|
I had noted that the glass fuel bowl remained full so I mentally eliminated any gas line issue. The carb was tight and seemed fuel ready, so now the pump jumps into the spotlight...thanks for the input
|
|
| supereal | -- 05-24-2010 @ 10:24 AM |
|
Seeing the glass bowl full doesn't address the quantity being delivered. If you have the equipment, you can test the vacuum side of the pump. The pressure side doesn't mean much if the fuel line is partially clogged. As you say that the fuel pump does catch up when engine speed increases, I would suspect either the pump is weak, or the line is clogged. We routinely replace old pumps, anyway. They are not expensive, and the new ones are safe from the new gas.
|
|
| TomO | -- 05-25-2010 @ 7:08 AM |
|
The new pumps from Airtex may not deliver enough fuel to make the engine run reliably. Test your pump for fuel delivery before replacing it. The test procedure is: Disconnect the fuel line at the carburetor and direct the output into a measured container and crank the engine until you get 2 ounces of fuel in the container, then crank the engine for 15 more fuel pump discharges. You should have pumped at least 6 more ounces of fuel. If you have enough fuel delivery, I would spray carb cleaner into the main jets. Remove the drain plugs and use the straw to direct the cleaner into the jets. Tom This message was edited by TomO on 5-25-10 @ 7:11 AM
|
|
| supereal | -- 05-25-2010 @ 10:34 AM |
|
Tom: The Airtex pumps I was recommending are the electric type, and we haven't had any problems with them. Many of the new mechanical pumps we are now getting have a kind of exotic linkage that is supposed to be "new and improved". Time will tell.
|
|
| bigvince | -- 05-28-2010 @ 12:12 AM |
|
The cold issue sounds related to a choke adjustment. Is your choke closing fully? If it's starting and then stumbling and then smoothing out, your cold fuel delivery may be lean. Obviously oyu're getting plenty of fuel once the engine warms up.
|
|
| EFV-8 Club Forum : | https://www.earlyfordv8.org/forum |
| Topic: | https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=18&Topic=1287 |