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O.K.

This little(?) beastie is ready to come home. However I need to wrap my head around a small problem. The shop told me that they have a hard time getting the car to fire in the morning until they started hooking up an electric fuel pump. Without the electric fuel pump it seems the gas drains out of the carbs. Now granted the carbs have not been rebuilt so that may solve the problem for the long term. For now I may just go with the elec pump until I can afford to have the carbs done. Also what about putting in the elec. as a feed to the mechanical pump or should I just bypass the mechanical pump altogether.

My 56 does the same after sitting a few days even with rebuilt carbs so have an electric pump at the tank end. Controlled by a switch under dash, I turn it on a few seconds before & while starting engine and then switch off. Saves a lot of cranking time.

Packard V8--From what I have seen/fixed GM used resistors and Mopar used the resistive wire, and that resistive wire on the Mopars liked to fail.

An electric pump for priming is good, saves the battery. Some that have gone over to electronic ignition have learned the hard way what happens when you crank the starter for too long a period to pull fuel to the carb--the voltage drops below what the Petronics unit needs and the car still won't start, the electric pump gets the fuel up there and saves the battery from needless drain.

O.K off to the parts house to get an electric fuel pump.

Now for the biggie. I have got the car home but it seems to have forotten that it is a V-8 since it is running on only 6. The two middle cylinders on the psngr side are not firing. There is spark to the plugs, the plug are dry and brand new. All of the tricks have been done and from all of the people that I have talked to, outside of rebuilding the heads and doing the valves, the concensus is to try and run it at speed and see if the valves pump up and allow them to move as intended. The mechanic used a feeler gauge about the thinness of paper and could not get it thru the gap. Anybody got any other ideas.

Just because the plugs are brand-new doesn't mean they might not be defective.

Also, have you run a compression test - dry, then wet - on all cylinders that supports an issue with valves?

Packard did have a problem with sticking valve in the '55s, IIRC, but changed the stem finish.

BH

according to the mechanic a compression test was run. The way he determined that they were not firing was to disconnect the plug wires and there was no decrease in RPM. One thing I am confused on is the car runs rough at idle when it is cold, however once it is warmed up and you raise the RPM's it runs smooth as silk. I would think that with 2 cylinders not firing it would still run rough somewhat. In any event it is running and as soon as I hook up the elec. fuel pump it will at least move around the garage and on and off the trailer until I can come up with enough money to rebuild the mechanical fuel pump and the carbs. There is much I can do for now that does not involve major money.

Disconnecting a plug wire is a good old trick to ID a cylinder that's not firing (provided your careful in handling the wires), but that doesn't really tell you whether the localized condition is due to a problem with a plug or lack of compression. The latter can involve either rings or valves - hence the need to run both a dry, then a wet test.

Should be easy enough for you to remove the plugs on the affect cylinders and test with a voltmeter. If all else fails swap with a plug from a cylinder that does fire and see if the miss follows. Of course, I'm assuming your mechanic checked for spark at the end of the wires on the affected cylinders and found no problem.

Given your description, at this point, I doubt if it's anything more serious than valves or rings - like pistons. Still, I'd be curious to see compression test figures (both wet and dry) cold, then fully warmed (where it seems to overcome the misfire).

If the test results point to valves, it is not that difficult to pull a cylinder head and inspect things. Whether you fix only the affected valves (which a good mechanic can handle) or do a full refit for unleaded fuels (which would require a competent machine shop) depends on your budget.

Unless there is some serious wear, you could overhaul the pump and carbs yourself. I suspect kits would go about $50 a piece these days.

These guys are your buddies when it comes to Fuel pump and carb kits

http://www.maritimedragracing.com/then_and_now_automotive.htm

If you are not confident about the carb you could send it to Daytona in Florida, they are top-notch, the thing will look better than new and work the first time you try it, only needing minr idle adjustments.

this may be just an exercise in futility, but before I crawl underneath the car and go thru the trouble of installing an electric fuel pump, I am going to install the brand new pump that I got using the info found out here for the Ford cross-over part. Now it does appear to be a bit smaller and may not perform well trying to feed those twin 4bbls under high RPMs, but it should suffice for around the driveway. I just want to see it will hold the gas in the line as it is supposed rather than letting the gas seep out as it is doing now. If that works then I will look to rebuilding the old pump. If it does not work then I guess I will have no choice but to go with the electric one.

so does it sound like those two cylenders eventually "kick in" as the engine warms up? could they be getting fould by oil, say by defective valve seals when sitting, then cleaning off as the engine runs?