Four Carbs, all loading fuel at bottom of intake

[70bigblockdodge]

That's great compression test. Is the choke on when you are having these problems? The vapor is not really a problem but the liquid fuel is a little concerning. Those Eddy carbs don't have a pull off, they just use a bypass valve in the choke plate so they can tend to run rich during warm up. I would make sure the choke thermostat is warming up with key on. You may need to adjust thermostat so it comes off faster. Should say rich and lean. Rotate it toward lean so it can come off earlier. Get it solidly warmed up and then make adjustments.

 

[sprice]

That's great compression test. Is the choke on when you are having these problems? The vapor is not really a problem but the liquid fuel is a little concerning. Those Eddy carbs don't have a pull off, they just use a bypass valve in the choke plate so they can tend to run rich during warm up. I would make sure the choke thermostat is warming up with key on. You may need to adjust thermostat so it comes off faster. Should say rich and lean. Rotate it toward lean so it can come off earlier. Get it solidly warmed up and then make adjustments.

Yes, its working properly. Thanks.

 

[CBODY67]

Also reading last night about this running better with pvc hose off and came across this DF-17 adjustable PCV valve. I am pretty sure no vacuum at idle at the pcv when it was connected and running at idle. Thought they were all the same, if it rattles- you’re good, if no rattle - replace or clean. If I find the answer, will post back. Thanks and Happy holidays to all.

There IS flow through the pcv valve at hot base idle. This is a part of the fuel curve in the carb, too. The manifold vacuum pulls the valve "up" (against spring pressure) so that all air goes through drilled orifices in the valve plunger in that mode. With decreased vacuum levels, the spring lets the plunger move more toward "open", then closing fully when manifold vacuum goes away or greatly decreases (i.e., WOT).

In many cases, the flow through the pcv valve is either "the same" or "close enough" to allow one valve to go many places, especially as the particular vehicles age and "factory OEM' performance is not a big concern, by observation. The ONE difference I know about, in the small block Chevy realm of things, is the pcv for later 1970s L82 engines, which have a purple dye on the metal part of the valve. Allegedly more flow than the normal valve, which is supposed to allow more idle air for the wilder L82 cam. I also suspect that in relation to "cfm" rating, it might be more like a 10% increase (if that much). When starting in the approx 1.4cfm range, would not really be much at all. BTAIM

The other reality is that an OEM-spec Chrysler valve should be what you're using, I suspect. Whether NOS or replacement stock.

Just some thoughts,
CBODY67

 

[sprice]

I got everything back together. It started without priming with a dry carb, choke on, pvc hose off, port open. This surprised me because I have had to prime with the pedal before. Cleaned the plugs so tip is close to new in color. Would not idle down below 1000 but ran smooth. Idle screw adjustment did show some difference. Passenger side would stall the engine, driver would lower engine speed. Vacuum was 20 Hg at this idle spot, higher than the 15-16 prior. Didn't have the timing light hooked up, however was not moved however from where it was before disassembly. Removed a plug after about three - five minutes running and it came out same color as went in, so that's very encouraging. Exhaust fumes seemed normal. Tried moving my finger to half and then three quarter closed on the pcv port with some noticeable change. At completely closed, it stalled out. I' m thinking this is where the fine tuning needs to be studied.

 

[sprice]

UPDATE: Seems the issue was the fuel pressure guage was defective showing a lower pressure than it should be. Reduced the pressure at the regulator to its lowest pressure setting and I can set the idle screws as it should be. The exhaust is bearable and the plugs are correct color after a run. Was ordered as a stock fuel pump (Carter). Perhaps something funny inside. Anyway seems like we are good now. Thanks to all.

 

[1970FuryConv]

Good Work!

 

[fury fan]

Older thread, but man, what a good read!

Lots of 1-part-at-a-time swapping, a teardown to basics (the timing chain), correction of a problem, a confusing manufacturer's instruction sheet, and then ultimately a faulty diagnostic tool (the fuel pressure gauge) WITH a faulty fuel pump. Doesn't get much tougher than this!

And we blew away that old adage of 'most carb problems are found in the ignition'.

This thread is definitely being saved for my future reference.