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#1
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Hard starting SOB...
Trying to figure out why my father's car is so cold blooded. It literally will not start unless I squirt starter fluid into the carburetor. Once running, it runs great. The engine is a freshly rebuilt 400, rebuilt to stock 72' specs. Carburetor was redone by Ken @ everyday performance. He did the Qjet on my 72' Monte Carlo, it was great right out of the box.
I am going to try to reverify the base timing. But, I am also thinking that the choke could be an issue. Any suggestions are appreciated. TIA
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1972 Chevelle SS 2dr hardtop 454 LS5 4 spd - "Pure Stock" 1969 Chevelle 2dr hardtop L72/M20 - my "retirement" project. 1968 Chevelle 2dr hardtop 6.0/80E - pro tour-ish 1972 Monte Carlo turbo 6.0/TH400 2001 Silverado RCSS LQ4/80E swapped, cam, headers, FBO. 1972 E lCamino SS AFR headed 454/TH400 - the old man's project |
#2
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probably a choke issue. the choke should be pretty much closed on startup. you'll also need to ensure your accelerator pump is working.
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1979 Firebird Trans Am 301/4spd (Now 428) 1977 Firebird Formula 400/Auto 2007 Grand Prix GXP 5.3L |
#3
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WHAT CAR???
1. IS THERE FUEL IN THE FLOAT BOWL WHEN YOU CRANK THE ENGINE? Common for the float bowl to be empty, so the engine has to crank long enough for the fuel pump to supply fuel to the carb before it starts. 2. What is cranking compression? 3. How much voltage at the coil during cranking? 4. Does the choke shut fully? 5. Points ignition? Is the condenser in good condition? |
#4
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Most likely the choke operation is the problem, It should be completely closed with slight tension on it when completely cold. If not, you'll be pumping the accelerator 10 times to get it to start cold and constantly feathering the gas to keep it running for the first few minutes.
Another problem could be the bowl plugs leaking and emptying the fuel bowl overnight, and having nothing in the fuel bowl upon start up would also necessitate getting fuel/ether into the intake tract. Q Jets are notorious for this problem and removing the carb soon after driving and keeping it level and upright will allow you to lift it up overhead to see if in fact the bowl plugs are leaking fuel. The odd shaped hole between the primaries is where you'll see fuel seeping. If the problem is after a few days of sitting the deathanol laced fuel will evaporate also leaving the float bowl empty. |
#5
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Yup, leaking well plugs would be my guess..
On carbs with this condition, i like to spin the engine 3 or 4 revolutions before working the pedal. Then pump the pedal several times, then crank some more. This gives the fuel pump a chance to fill the float bowl before setting the choke. What ever happened to those hi density foam pads that came in the carb kits that would sandwich between the base and body under the bowl? Guess they went away with the leather accelerator pumps.
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Bull Nose Formula-461, 6x-4, Q-jet, HEI, TH400, 8.5 3.08, superslowjunk Last edited by Blued and Painted; 10-20-2016 at 06:32 PM. |
#6
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How come when a car has a problem its a SOB
But when the car preforms well, it's a She Guess i need some automotive gender diversity training.
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Bull Nose Formula-461, 6x-4, Q-jet, HEI, TH400, 8.5 3.08, superslowjunk Last edited by Blued and Painted; 10-20-2016 at 06:48 PM. |
#7
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Or simply fuel evaporation, potentially from excess heat of an over-active exhaust crossover in the intake manifold.
We called 'em the "Tomco Tampon"; NAPA used to sell them individually--although I can't instantly find a part number. |
#8
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Those foam pads were a complete POS, and never did anything to help that issue.
We also see a good many of these carburetors leak at the front plugs as well. The only real cure for leaking bottom plugs is to remove them and install screw in plugs coated with Marine Tex or Devcon....IMHO. Fuel leaves the carburetor in three ways, evaporation, drains back, and at the bottom plugs. At best after a hot shut-down it the bowl will be pretty much dried up in about a week. Even so the fuel pump should have fuel back in the bowl after a few cranks of the starter. If it takes many cranking cycles and the engine is still hard to start check pump shot and make sure the choke flap is tightly shut, one of these will be the issue......Cliff
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#9
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Oh, my side hurts while rolling in the floor.
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Bull Nose Formula-461, 6x-4, Q-jet, HEI, TH400, 8.5 3.08, superslowjunk |
#10
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Quote:
The new stuff is a joke. Not even a good sponge. It's like they shrink when gas(?) or what ever it is gets on them. Clay
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All the federales say,they could've had him any day They only let him slip away, out of kindness...I suppose Poncho & Lefty |
#11
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Clay, you are correct, and I have had to remove thousands of them with a pocket knife installed from kits decades ago. In not one single instance did any of those foam pads seal up the bottom plugs for very long.
Just about as bad is dabbing JB Weld over them, it gets soft and peels right off with a little help from my knife. Even when it looks like the JB Weld has stuck well, it fails an air pressure leak test 100 percent of the time....FWIW....Cliff
__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#12
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"In not one single instance did any of those foam pads seal up the bottom plugs for very long."
--Anything to get it past that 12/12 warranty Im well versed in q-jets but i would definitely send that operation out to some one with experience and is set up with the proper tools and equipment.
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Bull Nose Formula-461, 6x-4, Q-jet, HEI, TH400, 8.5 3.08, superslowjunk Last edited by Blued and Painted; 10-21-2016 at 04:00 PM. |
#13
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I had hard cranking issues with my 66 327 Corvette. My fuel pump went out on a road trip and I replaced it with the correct one it has started on the first turn of the key ever since. Makes me think it was weak at cranking RPMs.
Last edited by supercar; 10-23-2016 at 11:16 AM. Reason: spelling |
#14
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Cliff, have you ever used the green Loctite made for sealing porosity on those well plugs? Just curious if that is a way to seal the plugs without removing them. I used it on a few Q-jet rebuilds, but never saw them again, so not sure how well it worked. Maybe the fact that I never heard back from them is an indication that it might have worked. I would place a puddle of it on the plugs, and let it sit for a while to seep into any possible leaking spots, then wipe off excess after a 1/2 hour or so.
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Paul Carter Carter Cryogenics www.cartercryo.com 520-409-7236 Koerner Racing Engines You killed it, We build it! 520-294-5758 64 GTO, under re-construction, 412 CID, also under construction. 87 S-10 Pickup, 321,000 miles 99Monte Carlo, 293,000 miles 86 Bronco, 218,000 miles |
#15
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On Chevys with fuel issues many times I found fuel pump push rod bent!
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
#16
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"Cliff, have you ever used the green Loctite made for sealing porosity on those well plugs?"
No. I've seen a number of attempts to seal bottom plugs, and nothing is going to work permanently aside from removing them and installing screw in plugs coated with Devcon or Marine Tex. It amazes me to this day how good some of the sealing jobs look, but 100 percent of the time if the plugs are leaking they dabbed on glue fails a leak test with compressed air. Most leaks that cause running issues and difficult hot restarts are the front plugs, not the rear ones. The rear ones are encased in the lower gasket, where the front plugs leak gas directly into the intake. Front plugs are also much smaller and very difficult to get the material around them clean enough to hold any type of epoxy anyhow. We drill those plugs out here, and tap the casting for screw in plugs, it is a permanent repair and to date we've never got one back that leaked......Cliff
__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#17
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Quote:
Crank it for 5-10 seconds, then see if you get a pump shot. If not then replace the fuel pump.
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1969 Lemans vert, matador red, 462 CI, 3.07 12-bolt posi 1974 455 TA, admiralty blue/red interior HPP "cover car" - sold "The best way to show a car is to drive it" |
#18
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im gonna say a little bit about what we found with my friend's California sourced chevy nova...ran and drove fine..if it sat more than a couple of days, you could not get it started without pouring gas down the carb. after that, ran fine. well to spare you all the swear words and labor, come to find out it was the rubber fuel lines were dry rotted---not enough to leak; but enough to suck air at the top cracks that the fuel pump couldn't prime. we replaced the rubber lines at the tank and up at the fuel pump. car started every time after that.
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#19
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Yes, that's a big issue also, fuel pumps suck in air much easier than fuel given the choice!
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
#20
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Quote:
__________________
1972 Chevelle SS 2dr hardtop 454 LS5 4 spd - "Pure Stock" 1969 Chevelle 2dr hardtop L72/M20 - my "retirement" project. 1968 Chevelle 2dr hardtop 6.0/80E - pro tour-ish 1972 Monte Carlo turbo 6.0/TH400 2001 Silverado RCSS LQ4/80E swapped, cam, headers, FBO. 1972 E lCamino SS AFR headed 454/TH400 - the old man's project |
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