Mysta2 Posted May 23, 2019 Report Share Posted May 23, 2019 I have a '79 620 truck that I can't get started. L20B (I assume) with an edlebrock intake and a Webber carb (all installed by the PO) It started a week or so ago in the middle of the night in the garage and ran for a while. This was a test after fixing some of the ignition switch wiring. Now, without any changes it will not start. I can switch the ignition on, and can hear the fuel pump running. It cranks nice and strong but doesn't even try to start. Spraying starting fluid in the carb does nothing (usually it helps with a hard start after a long sit) So this suggests to my mind that the issue is electrical rather than fuel. I'm on my own in the garage so I don't have anyone to test things in the engine bay as I crank it. I did notice that the distributer was loose so I placed it in generally the middle of the slot and tightened it down a bit. New development as of last night: I pulled the plugs and found them to be very black and wet. I cleaned them all and put them back in and it seems to have tried to start. It shook a lot but didn't catch. Then after that first burst, it was back to cranking with no effort to start. I went down to Oreilieys and bought new plugs, put them in and same thing: one shaky almost start, followed by cranking but nothing. Is there a location to best set the distributer to get the thing running in order to set it? Other ideas on next steps? Quote Link to comment
Crashtd420 Posted May 23, 2019 Report Share Posted May 23, 2019 So since you have no help are able to verify spark or it an assumption? You can make a connection between the spade terminal on the starter and the battery positive with some wire and a push button..... even just touch the wires together and it will start cranking..... Obviously turn the ignition key to the on position and crank the motor with the external button to see if you get spark.... There could be a few reasons why it wont start..... Ignition switch, or even the ignition module with the distributor could be bad.... Distributor should be close enough where you have it.... maybe try advancing it a bit and see if that helps too.. 1 Quote Link to comment
Stoffregen Motorsports Posted May 23, 2019 Report Share Posted May 23, 2019 Looks rather crusty. Has it been sitting for a while? Bad gas is my first thought. Plugged or gummed up carb. Have you looked down into the carb while you're working the throttle? Does it squirt gas? It could also be victim of very worn rings. That would foul the plugs and cause enough leakdown in compression that it would have a hard time starting. Try leaning into the throttle as you try to start it. Not wide open, but gradually increasing the throttle. Also, try running a wire directly from the battery to the coil and then try starting it. If this helps, your ignition system is weak. Without knowing the history, it could be a million things. Improper cam timing or ignition timing, etc. 1 Quote Link to comment
Crashtd420 Posted May 23, 2019 Report Share Posted May 23, 2019 Is this a new project? Has it ever ran for you? 1 Quote Link to comment
banzai510(hainz) Posted May 23, 2019 Report Share Posted May 23, 2019 (edited) adjust the dist maybe it will fire off. wet plugs could mean its flooding out like a float issue on the carb. I notice on your weber you have 2 fuel hoses going to it. I never seen this hooked up like that before. Maybe Stoffregen knows more about how that works, I return line? I would adjust the valves and see where your dist rotor is pointing at TDC (crank zero) and see how far off you are. If you have spark and gas it should fire off if compression is good Edited May 24, 2019 by banzai510(hainz) Quote Link to comment
Draker Posted May 23, 2019 Report Share Posted May 23, 2019 I second the timing. Make sure this is set correctly. You could be 180 degrees out on the distributor, which would wet the plugs and stumble a bit. Or the oil pump spindle could be a tooth off which would cause your distributor to be way off. If I was to place a bet on anything wrong with it, it's probably the dizzy if off because of the oil pump drive spindle. Set the crank at TDC, take the valve cover off, look at the timing mark there. Then pop the dizzy out (DO NOT DISCONNECT THE SPARK PLUG WIRES), look down the hole. Look at this post for reference: On 2/21/2018 at 6:52 AM, datzenmike said: Set TDC using the timing scale and the notch on the crank pulley. You MUST only turn in a clockwise direction to set this. If you overshoot the mark back well up and re-try. May take a half dozen tries but you cannot back up to set TDC, only turn in a clockwise direction. This will keep all the chain slack on the passenger side and make the cam timing check accurate. Once TDC is set.... 1/ The V notch in the cam sprocket should be just under the line on the cam thrust plate behind it and just a tad to the right of it looking at it from the front. Cam number does not matter as long as you get this. L16s are set at #1 at the factory. L20B and Z series are set #2. 2/ Now check your distributor timing. Should be like this... If timing the distributor requires turning to extremes maybe you have the wrong pedestal or see if the adjustment plate can be flipped upside down. In some cases this is what has happened, however you can drop the oil pump and re-position the drive spindle to (say) 11:35 and this moves the distributor rotor under one of the wires under the cap. Hopefully #1 but if not... this wire now becomes the #1 and the others follow counter clockwise 3, 4,and 2. . Quote Link to comment
datzenmike Posted May 24, 2019 Report Share Posted May 24, 2019 Ignition switch problems... start here. Pull coil wire off and hold or place near a ground and turn engine over with the starter. Got spark. If not start right there..... Crank with the starter for 5 seconds then quickly look down the carburetor. Is it dripping? Yes? carb is flooding so fix this. 1 Quote Link to comment
Mysta2 Posted June 11, 2019 Author Report Share Posted June 11, 2019 Carb does not seem to be dripping after 5 seconds of cranking. I had my son try and start it from inside the truck and I confirmed spark at the center dist wire. In the original post I stated that it was running a week before the post. I’m not sure what you’re asking when you ask if I’ve ever had it running. That being said though I have never had it running with any consistency or driven it more than up and down the street, so if you mean that then no. update: I got it running and although it smoked a lot, it did idle alright for 5-10 minutes before it started to run a bit rough and then I shut it off. Quote Link to comment
thisismatt Posted June 11, 2019 Report Share Posted June 11, 2019 Fuel pressure regulator on that electric pump? Quote Link to comment
Mysta2 Posted June 11, 2019 Author Report Share Posted June 11, 2019 27 minutes ago, thisismatt said: Fuel pressure regulator on that electric pump? Not that I can think of at the moment. The fuel pump is original as far as I can tell, sure looks it at least. Quote Link to comment
datzenmike Posted June 11, 2019 Report Share Posted June 11, 2019 Only the '79 with air conditioning had the electric fuel pump, and it was located on the outside of the rear right frame just forward of the rear tire. All others had the mechanical pump on the front right side of the head. Webers are sensitive to too much fuel pressure so 3 PSI or just under is probably best. If it was running well but suddenly started having problems then this narrows down the possabilities, this is much different from never having run properly where anything could be wrong. Quote Link to comment
banzai510(hainz) Posted June 11, 2019 Report Share Posted June 11, 2019 float sinking causing to much fuel but once running might be ok as its using fuel. I'm not a 79 expert so it might have a electric pump hopefully stock. if WAS RUNNING BEFORE THEN I THINK IT WOULD BE THE FLOAT SINKING OR THE NEEDLE VALVE DIRTY and not closing fully thus causing a overflow condition Quote Link to comment
datzenmike Posted June 11, 2019 Report Share Posted June 11, 2019 2 hours ago, datzenmike said: Only the '79 with air conditioning had the electric fuel pump, and it was located on the outside of the rear right frame just forward of the rear tire. All others had the mechanical pump on the front right side of the head. Webers are sensitive to too much fuel pressure so 3 PSI or just under is probably best. Pump stands upright and bolted to side of frame, looks like can of beer. Is this what you have? Other than stock is always suspect... may be too high a pressure. The stock pump is self regulated to about 3 - 3 1/2 PSI Quote Link to comment
Stoffregen Motorsports Posted June 11, 2019 Report Share Posted June 11, 2019 I have had more problems with needle and seat valves sticking in the past year than ever before. This new gas has some corrosive shit in it and just obliterates the rubber hoses, and that debris gets stuck in the needle valve. Or the fuel sits too long and calcifies into hard crust. Or, and this just happened the other day, the fuel corrodes the steel fuel filter which are common in many cars/ trucks. Two new fuel filters on my CJ5 turned rusty inside of 6 months. The rust chunks broke off and got stuck in the needle valve. I replaced them both with OEM Toyota plastic filters. DGV's are ok to about 4 psi. Quote Link to comment
banzai510(hainz) Posted June 11, 2019 Report Share Posted June 11, 2019 where the gas line goes into the carb tap it abit and maybe if dirty it will unlodge. Quote Link to comment
Mysta2 Posted June 11, 2019 Author Report Share Posted June 11, 2019 (edited) Yeah, I'm fairly certain it's original: (maybe more like a can of RedBull) I've broken it down a bit (long time ago) to make sure it's clean inside and it seems to work well. Edited June 11, 2019 by Mysta2 Quote Link to comment
banzai510(hainz) Posted June 13, 2019 Report Share Posted June 13, 2019 change out that filter Quote Link to comment
Mysta2 Posted June 13, 2019 Author Report Share Posted June 13, 2019 There are two filters in line. That one and another in the engine bay. That photo's a year old and I'm not sure that's the filter that's still on it as I have changed them both. I may go ahead and swap them both again for the hell of it though on the chance that it might help. That 90 degree one was a pain to find. Quote Link to comment
Stoffregen Motorsports Posted June 13, 2019 Report Share Posted June 13, 2019 Beck Arnley - p/n - 0438002 Wix - p/n - 33053 Quote Link to comment
banzai510(hainz) Posted June 13, 2019 Report Share Posted June 13, 2019 that 90 deg one is a common part. Fram makes them also. my 510 521 is the same. Rockauto has them also. I got to change mine out every 2 years 521. the truck tanks are exposed and water runs into the fuel neck and into tank causes rust and dirt to get in. from the wheelwell down the tube under the clamp. I had a carb idle jet plugged . clean out and within a minute plugged up again!!!!!!!!! Quote Link to comment
Mysta2 Posted July 16, 2019 Author Report Share Posted July 16, 2019 (edited) Update: She's a runner now... I didn't really do anything to address this actual problem short of just kind of "working through it". Starts on starter fluid now, and idles well (as far as I can tell) but it does smoke a hell of a lot. Video (if this works) Try this video: https://photos.app.goo.gl/RScpBSj9uF7CP9UZA Edited July 17, 2019 by Mysta2 Quote Link to comment
banzai510(hainz) Posted July 16, 2019 Report Share Posted July 16, 2019 pumping the gas pedals before start should be like using starter fluid 1 Quote Link to comment
datzenmike Posted July 16, 2019 Report Share Posted July 16, 2019 This. Pumping works the accelerator pump and squirts gas into the intake. Make sure the choke flap closes after the first pump. 1 Quote Link to comment
Mysta2 Posted July 17, 2019 Author Report Share Posted July 17, 2019 What would cause the choke flap to close? The choke is setup currently as manual. Would the accelerator pump only spray fuel with the electric pump running? Or should it do it all the time? I can't see any spray in either condition: Video: https://photos.app.goo.gl/YihNz24xb5BqrLJq6 Are these video links working? I put them into a shared Google album. Quote Link to comment
datzenmike Posted July 17, 2019 Report Share Posted July 17, 2019 With a manual choke the linkage pulls the choke closed when you pull the lever. The accelerator pump draws fuel from the fuel bowl in the carb and squirts it into the primary barrel to compensate for the lean condition during the transition from idle to low speeds. As long as the fuel bowl has gas in it, the accelerator squirts gas as you step down on the gas pedal. The electric fuel pump merely delivers gas to the carburetor. If the pump is off the carburetor would eventually go dry if you pump the accelerator pump enough times. Enough times to do this would thoroughly flood the engine. Quote Link to comment
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