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no fuel to carb 79/350josh_h31 12-24-2006, 05:24 PM no fuel geting to carb.new fuel pump. any ideas?? josh_h31 12-24-2006, 05:31 PM new fuel pump, still no gas to carb any clues? MT-2500 12-24-2006, 05:55 PM new fuel pump, still no gas to carb any clues? Not much info to go on there. Gas in tank? I would put some gas in to make sure.:grinyes: Will it pump gas to carb? How long have you cranked engine? Is the fuel pump rod moving? Will engine start with a little gas prime in carb? Hook a hose on fuel pump inlet and run other end in a gas can and see if it pumps. For a fuel tank or fuel line check. Have you looked the gas line from tank to fuel pump over for bad hose or line? And if all else fails blow air back threw the fuel inlet line but remove gas cap so you do not blow up tank.. Some of the the sock in the tank stops up. Enough air pressure you can unstop it or blow it off. silicon212 12-24-2006, 05:56 PM Is there gas in the tank? I know this might seem obvious, but it does happen and we have to cover all bases. The fuel system on these cars is simple and straightforward. If there's fuel in the tank, and you're sure the new pump you have is good (failures out of the box are not unheard of), then there are a couple of places to look. One is the sock on the bottom of the pickup tube in the tank - requires tank removal, and another more readily checkable thing is the pushrod for the fuel pump in the engine. This rod mates with an eccentric on the camshaft on one end, your fuel pump rocker arm on the other end. Due to the presence of this pushrod, which can easily drop down rendering reinstallation of the fuel pump difficult at best, there is a specific method of fuel pump R&R. There is a bolt at the front of the engine, which is a part of a 4-bolt front engine mount provision (two bolts at the front of the engine, facing forward, above the oil pan rails on each side of the engine, 4 total). Three of these holes are empty, one of them will have a bolt in it. If your car has a smog pump, then both passenger bolt holes will be used to mount the bracket and the pump will have to be removed. This will be the upper bolt on the passenger side of the engine. What you do, BEFORE you remove the two bolts that hold the pump on, is to remove this bolt (which is about 3/4" long if memory serves), then thread a 1.5" long 3/8 16TPI bolt into it until the bolt bottoms - but DO NOT FORCE IT TIGHT! You only want to snug the bolt, that's all. This bolt has bottomed on the fuel pump pushrod and will hold it in place and prevent it from dropping. Remove the old fuel pump, after removing the fuel input and output lines of course. Check that the rocker hasn't become damaged and if the pump is good, reinstall it or if it is bad, replace it. Don't forget to remove the long bolt and reinstall the original short bolt before you start the engine! If you don't put a bolt back, you will have a hellacious oil leak. *If the pushrod does drop, you will need to remove the two bolts that hold the plate on the block, and then remove the plate taking care not to let the pushrod drop out. Reposition the pushrod; then using a new gasket (with the old one scraped off), hold the pushrod up and snug that bolt, then put the plate back on (with the two bolts at the bottom of the plate only FINGER TIGHT at this point). Once you get the fuel pump installed and its bolts tight, you may tighten these two bolts to about 5 ft. lbs only (not much more than hand tight, think of the valve cover bolts* josh_h31 12-24-2006, 06:00 PM sorry,yes it will start with fuel in carb,not sure how to check the rod? cranked till bat almost dead josh_h31 12-24-2006, 06:17 PM Is there gas in the tank? I know this might seem obvious, but it does happen and we have to cover all bases. The fuel system on these cars is simple and straightforward. If there's fuel in the tank, and you're sure the new pump you have is good (failures out of the box are not unheard of), then there are a couple of places to look. One is the sock on the bottom of the pickup tube in the tank - requires tank removal, and another more readily checkable thing is the pushrod for the fuel pump in the engine. This rod mates with an eccentric on the camshaft on one end, your fuel pump rocker arm on the other end. Due to the presence of this pushrod, which can easily drop down rendering reinstallation of the fuel pump difficult at best, there is a specific method of fuel pump R&R. There is a bolt at the front of the engine, which is a part of a 4-bolt front engine mount provision (two bolts at the front of the engine, facing forward, above the oil pan rails on each side of the engine, 4 total). Three of these holes are empty, one of them will have a bolt in it. If your car has a smog pump, then both passenger bolt holes will be used to mount the bracket and the pump will have to be removed. This will be the upper bolt on the passenger side of the engine. What you do, BEFORE you remove the two bolts that hold the pump on, is to remove this bolt (which is about 3/4" long if memory serves), then thread a 1.5" long 3/8 16TPI bolt into it until the bolt bottoms - but DO NOT FORCE IT TIGHT! You only want to snug the bolt, that's all. This bolt has bottomed on the fuel pump pushrod and will hold it in place and prevent it from dropping. Remove the old fuel pump, after removing the fuel input and output lines of course. Check that the rocker hasn't become damaged and if the pump is good, reinstall it or if it is bad, replace it. Don't forget to remove the long bolt and reinstall the original short bolt before you start the engine! If you don't put a bolt back, you will have a hellacious oil leak. *If the pushrod does drop, you will need to remove the two bolts that hold the plate on the block, and then remove the plate taking care not to let the pushrod drop out. Reposition the pushrod; then using a new gasket (with the old one scraped off), hold the pushrod up and snug that bolt, then put the plate back on (with the two bolts at the bottom of the plate only FINGER TIGHT at this point). Once you get the fuel pump installed and its bolts tight, you may tighten these two bolts to about 5 ft. lbs only (not much more than hand tight, think of the valve cover bolts* thanks will give that a go. MT-2500 12-24-2006, 06:39 PM sorry,yes it will start with fuel in carb,not sure how to check the rod? cranked till bat almost dead The rod is what works the fuel pump arm. If you are not careful installing the fuel pump you can miss the rod and break your fuel pump arm. A quick check is to loosen the fuel pump mounting bolts up a couple of turns and see if the fuel pump is rocking when cranking. If no movement. Did you not feed the rod on top of fuel pump arm when you installed it? Blue Bowtie 12-25-2006, 07:49 AM And, FWIW, if you suspect the pickup strainer (sock filter) in the tank is clogged, I've had moderate success removing the fuel tank cap and blowing backward through the fuel supply line with compressed air to clear the sock filter. bobss396 12-27-2006, 10:02 PM Try the air hose thing first. Next, physically go over every inch of the flue lines from the tank to the fuel pump. I had a rotted out rubber gas hose on an older Impala that was high up under the body (on a wagon) that was sucking about 99% air instead of gas. The steel lines along the frame are prone to rusting out too, might be worth a look too. Bob vBulletin®, Copyright ©2009, Jelsoft Enterprises Ltd.
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