I will put a longer stiffer hose on but i temporarily fixed it. Car started right up this morning after installing the check valve fuel filter yesterday. I'll check it again after it sits over the weekend.
Took it out today. Still cranks a LONG time before it starts. I'm thinking the plugs are probably leaking on the bottom.
I think the factory recommends removing the carb, putting it up on level blocks overnight with paper towels underneath and checking periodically. If there is no dripping it's not the plugs.
There is still the Fuel Evaporation problem which is a large part of the symptoms of the extended cranking !
Leaking bottom plugs are somewhat rare on 1969 and later carburetors and nearly non-existent on most built from about 1975 and up. Even so, ALWAYS leak test the plugs BEFORE making repairs. Dabbing any type of epoxy over them is about as effective as cutting your arm off and putting a bandaide on it! Leaking rear plugs that can't be sealed by gently re-swaging the material around them should be removed and the casting tapped for screw in plugs coated with Marine Tex. Front plugs provide a DIRECT fuel path into the intake and are easy to diagnose. You will see vapor coming out of the carb after a hot shut-down, and the engine will act flooded after sitting for a few minutes. Almost ALL poor start issues are related to the accl pump. ALL fuel bowls will be low or empty after sitting few days, that's just the piss-water fuel we have to deal with these days. Think about it like this. IF I handed you a completely/correctly rebuilt carb and it's bone dry, your engine should roar to life the moment fuel returns to the fuel bowl provided you are pumping the throttle and the accl pump is putting fuel into the intake. IF you can't get it to fire up after several cranking cycles the accl pump is junk and/or you have a fuel delivery issue where fuel isn't returning to the carb. I wouldn't put much faith in any Youtube videos, resident "experts", guru's and others who tell you that a no-start condition after sitting a few days is a BOTTOM PLUG issue, that is nothing more than old, inaccurate, outdated regurgitated information. It's almost always an accl pump issue as these new "cheap" blue seals swell up in modern fuel and stick so tight in the bore the well under them doesn't fill well when you are pumping the throttle. Yes, the Q-jet doesn't use a feed check ball system to a swollen accl pump seal causes difficult or no-starts after the vehicle has sat several days........FWIW...... Below is a recent pic of three pump seals. The top seal was in a NAPA (Walker) kit for early carburetors that didn't use a garter spring under the seal. The second pic is the "blue" seal that shows up on modern garter spring style pumps, the bottom seal my lifetime warrantied part. These seals were soaked in E-10 fuel for a couple of days........
Thanks so much for replying Cliff. Yes bowl was dry again when I took it off this morning. Put fuel down vent tube and no leaks from plugs so far as you suggested. Replaced fuel pump but not accelerator pump yet. Accelerator pump squirts hard almost like new when fuel is in bowl but should definitely be replaced after 50 years. I'm thinking fuel delivery to bowl might still be the problem on long cranking? Also as long as carburetor is off I could drill out the idle circuit holes about 0.040"?
After sitting all day there's not a drop of fuel leaking. So I tried pushing the accelerator pump manually. First pump only a slight squirt. Second and following pumps very strong squirts. So it seems my bowl is drying up after a day or two and then I have a fuel delivery issue where fuel isn't returning to the carb while cranking. Filter with or without check valve doesn't make any difference.
What are "idle circuit holes" and why would you want to drill out anything in the idle circuit in the first place?.....
I posted pictures 4 posts back. I thought it might help my idle. Earlier posts by others suggest it may be a good idea. I believe the correct terminology is idle air bypass. My 350 has higher compression now with the silvolite pistons and the cam is the 284-88h.
Do you have full control with the idle mixture screws when it's at idle speed? Do you have "nozzle drip" at idle speed. Modifications to the idle system are done as a "recipe" and only when they engine choices that were made have the carb coming up short on fuel delivery. The carburetor for sure needs a complete/correct rebuild with good parts. I'd start there and see how things are working before you get the drill bits out.........
The idle screw adjustments do not change my vacuum or rpms so I just put them 2.5 turns out. Seems like it is barely running on the idle circuit. I was thinking 0.040" holes wouldn't hurt but if you think i should wait till after the rebuild next year i will.
The fuel hose needs to be shorter, not longer. Think about it.. Also, give the metal line that goes through the frame a little tweak downward. Holley carbs don't seem to be as afflicted with fuel disappearing as QJets. Maybe removing the little wire hanger on the needle along with installing a windowless seat would help. The needle wouldn't be pulled out of the seat as fuel evaporates and the float drops, opening the drain. Cliff?
This fuel just doesn't stick around very long. I've filled the fuel bowl of a Q-jet on the bench and it's pretty much down to nothing in 24 hours. It would disappear quicker after a hot shut-down and speeded up even more during the hot summer months. Even with that said that even IF I handed you a bone dry carburetor it shouldn't take long for fuel to fill the bowl and the engine roar to life. If you find yourself going to many cycles of cranking and still no pump shot to get the engine to light off you either have a bad accl pump (most likely cause IMHO) or a fuel delivery to the carburetor issue (have seen plenty of those as well).........
Thanks. Yes I checked fuel delivery by loosening line at the carb. Plenty of pressure and flow and immediate delivery when cranking. And then checked accelerator pump stream and it seemed great. Then I tried to start the car feathering the pedal. Lots of cranking then fuel started coming out the vents on top of carburetor. I flooded it. Then depressed pedal fully to clear and she started right up. Maybe I'll check if choke is closing enough next outing. Thanks so much for everyones help!
Hmmm, if you have a bad accelerator pump causing long crank times after sitting for several days, I would expect corresponding complaints of hesitation during acceleration and hard hot restart.
"Hmmm, if you have a bad accelerator pump causing long crank times after sitting for several days, I would expect corresponding complaints of hesitation during acceleration and hard hot restart." What is happening with these new "blue" pump seals is that they swell up and get tight in the pump bore. After sitting a while the pump bore does NOT refill when the pump upstrokes as the pump often sticks or just doesn't let fuel get past it, so you get poor pump shot on a restart. After you finally get the engine running and have "worked" the pump some they often work OK till the next shut-down, sitting for a while and drying up cycle. The seal will eventually stick so hard in the bore that the seal fails, and on the early pumps it comes off and gets all wrapped up on the return spring under the pump. I see this ALL THE TIME with these cheap/soft blue pump seals but it typically goes on deaf ears. Unless you can't see for chit there are pics above showing three seals soaked in E-10 for a couple of hours while I put on a class for some young mechanics last week. At the very beginning of the class on day one I removed the blue and black seals from pumps showing up in an Echlin and Walker kit and threw one of my seals in a small stainless steel bowl. I poured fresh 93 octane E-10 in enough to cover them. About 3 hours into the class we removed them for inspection and some pics. Here is a more dramatic example after 5 minutes in carb cleaner which speeds up the process considerably. The other pic is a carb that came in here 3 days after the owner rebuilt it with an on-line rebuild kit. He didn't want to buy any parts, just wanted me to take a look at it to see what he did wrong. I told him before he made the two hour drive down here that the pump seal had failed, but he told me very quickly that he'd been using NAPA kits since Moby Dick was a minnow and never had any issues with them.......
