I just replaced my valve covers and was working on my engine and got the thing started earlier and when I came out later it wouldnt start back up. I put some gas in the tank and carb, tried different spark plug rotations but cant seem to figure out why it gets right on the verge of starting up but never does.
Can anyone key me into some things to look for?
yogibare143
10-16-2008, 01:17 AM
Sounds like a bad Ballast Resistor. If truck starts and dies as soon as you let key off start position.
Mark
bherder
10-16-2008, 09:04 AM
You may also have moved/jiggled around some wiring while changing your valve covers, might want to check that all the connections around the area you were working around.
But as Mark says, sounds like a ballast. You can check by running a jumper wire from the + side of the coil to the + side of the battery. If it starts and stays running, your ballast is bad. (Don't leave your truck running for any length of time with a jumper, or you might ruin your coil)
1972-D100
10-16-2008, 09:09 AM
Are you getting a spark at all? test the voltage on the hot side of your coil with the key in the run position. A coil going out will also give you the same effect as a bad Ballast Resistor, works great when you are applying full voltage in the start position, but dies when only getting the half voltage in the run position.
Fnix
10-16-2008, 09:33 AM
Is replacing the ballast something a Novice DIY could do? They seem pretty cheap to me. Worth the shot. I'll jumper cable it and see.
1972-D100
10-16-2008, 09:37 AM
Yep, just to be on the safe side disconnect the neg bat cable, take both plugs off the resistor, be careful not to break the plastic plugs, remove the screw from the middle of the resistor. Replace in reverse.
Fnix
10-16-2008, 07:56 PM
If I wanna put some gas in the carb, how much and where at into the carb? Just the throat?
Chump
10-17-2008, 01:24 AM
Check near the back side of the passenger valve cover for a 6 or 8 position connector. Those can get loose, corroded or have broken wires.
bigdogscott
10-17-2008, 09:58 AM
if you put gas in carb just put alittle bit & if u have a 4 bbl put in front part of carb,2 bbl pour a litte bit in both parts of carb,pump gas pedel 1 time & try to start truck.
1972-D100
10-17-2008, 10:01 AM
Make sure to keep your hands away from the carb when you try to fire it, if your timing is a little too advanced it will cause a a flame to shot out the carb!
Fnix
10-17-2008, 11:13 AM
It started just enough to backfire once then just does the cranking over and not starting again.
Cant really tell if electrical or fuel pump problem. My engine only had about a gallon of gas when this all started. But I put some more in since.
1972-D100
10-17-2008, 11:34 AM
Try cracking the fuel inlet line on the carb and then have someone crack the motor, if you get gas then it is most likely an electrical issue... You may have gotten air in the lines before you added more fuel. If you crack the line and no fuel comes out just air you will need to bleed the line until all the air comes out.
1972-D100
10-17-2008, 11:36 AM
Also just a thought, did you move the distributor at all?
Fnix
10-17-2008, 11:42 AM
Also just a thought, did you move the distributor at all?
I just messed with the sparkplugs on it. Didnt move it to my knowledge because it started up and ran fine then didnt start 3 hours later after nothing was touched.
BTW, is the choke valve supposed to be %100 closed when the engine is off?
1972-D100
10-17-2008, 12:31 PM
I just messed with the sparkplugs on it. Didnt move it to my knowledge because it started up and ran fine then didnt start 3 hours later after nothing was touched.
BTW, is the choke valve supposed to be %100 closed when the engine is off?
It is an electric choke correct? I always use the manual type, but I think (could be wrong) when the power is off it goes to the closed position. Does it stay in that position with the key in the run position? Did you crack the line and check for fuel?
Speed Dragon
10-17-2008, 05:57 PM
Hmm, sounds like it could jumped time. Turn it over (by hand) to TDC on the compression stroke of #1 (take the plug out, and the comp stroke will be pushing air out of the hole), and see where the rotor is pointing. If it's not some what close to the #1 plug wire terminal, the timing chain may have jumped.
Otherwise, it could be a bad pickup in the dizzy as well. Or a engine ground that didn't get hooked back up or got broken. Pull the coil wire and hold it over the coil tower and see if you have spark from the coil to the coil wire. If so, check to see if you have it from the coil wire to the cap.
Fnix
10-18-2008, 03:22 PM
I tried the fuel inlet line trick and the jumper cable to ballast resistor. I think I'll have a friend of mine diagnose it for me. I have alot of old wires, wouldnt hurt to probably have them all redone neatly in the end. :cool:
fins2fuselage
10-18-2008, 09:10 PM
Fnix,
Do you have the firing order arranged 1-8-4-3-6-5-7-2? Just curious . . .
Jeff
Fnix
10-18-2008, 10:03 PM
Fnix,
Do you have the firing order arranged 1-8-4-3-6-5-7-2? Just curious . . .
Jeff
Yeppers
fins2fuselage
10-18-2008, 10:16 PM
Fnix,
Is the ignition module adequately grounded to the firewall?
Also, did the engine ground strap(s) to the firewall get re-installed when you replaced the valve covers? Since the ignition module is grounded to the body, the body can't be isolated from the engine.
Jeff
Fnix
10-20-2008, 06:35 PM
Ok got it running.
Main problem was an advanced timing and lots of gas in the cylinders + spark plugs that were about 10 years to old. So I had the timing fixed, new distributor cap and new plugs put on. Runs better then before now.
yogibare143
10-20-2008, 10:34 PM
Glad You got it going! Sometimes the little things will get you.
