Ok I'm reaching the end of my rope here so here goes.... I've got a 71 Riviera with 455 BBB, engine has been rebuilt top to bottom, and the only change from stock is a TA 212 cam. Ran fine at the end of the last season, vacuum advance on the distributor quit working right before I put it up. Had a bright idea to just switch my distributor from the stock one to one of those fancy MSD R2R distributors, Blaster Coil and wires. Installed everything and the engine would crank, but no start. After running the gambit on my side, I called MSD and they concluded I had a bad unit, they shipped me another one and I had the same issue. So I finally ripped all the MSD stuff out except the Blaster coil, put the stock distributor back in, turned the key and it fired right up. So I shipped all the stuff back and went to buy a vacuum advance module from the local parts store, replaced it with the distributor still in the car, and now it wont start again. I replaced the coil, wires, cap and rotor, negative battery cable, and still nothing. It will crank all day long, but it wont even sputter. Tried ether and nothing. Reset dwell and distributor advance, still nothing. The timing light will still flash, even if the inductor is way back at 8, so I have to imagine I'm getting good spark. I'm running out of ideas. Any help would be super appreciated. Thanks in advance! (Timing joke)
Do you have a voltmeter? If so get a helper, set it for D.C. Volts and check how much voltage you read on the + terminal of the coil when cranking and report back with that info. My guess is that you have very weak spark, like just enough to kick on a timing light but not light off a charge in the cylinders.
I'm reading 10 volts DC when cranking. And the points passed the tests you linked to Larry. 5.5 when closed with key on. And 10 volts when cranking.
Does your solenoid on the starter have a wire on each of the small terminals? You should have a full 12 volts from the batter when cranking which means you should have 2 wires on the + terminal of the coil. One wire from the resistance wire that provides 9 volts or so when the engine is running and the key is off the Crank postion, and then a full 12 volts applied to the coil when Cranking by means of passing 12 volts thru the starter solenoid and back up to the coil. You need a full 12.volts with a points system to cold start the motor! Also needed for a cold start is to have the choke closed up all the way, once the motor starts then it should pull open to the tune of 1/8 to 3/16" for high idle to happen.
Just a thought, You may have fuel fouled your plugs while trying to start with the faulty distributor. Has happened to me and several friends
The last thing you did was replace the vacuum advance, and then it wouldn't start. I would start there. They can be a bear to install as far as screw access. Is it possible you broke the wire from the distributor to the negative side of the coil. Do a continuity check between the negative side of the coil and the points. Make sure the wires attaching to the points do not touch the base plate. Recheck point gap. You are missing something if it doesn't even try to fire. At this point, I think you may need a fresh set of eyes on this.
Ok so I pulled the distributor and put it on a well lit bench and took a look at everything. I pulled it all the way apart, checked the wiring and, reassembled. The only physical issue I noticed with the distributor is that the shaft can move up and down very slightly, and when it moves down it binds when I spin it. I have to assume that's not normal. The big surprise however is that when I put the points back on and tightened everything down, there was a quarter inch gap between the points, which doesnt make any sense because I never changed the settings. I was unable to adjust them enough to make them touch. So I went and purchased a new set and they fit perfectly. I have them adjusted properly via the service manual for an initial setting. And it still wont fire. At this point the entire ignition system has been replaced. I switched to thinking it could be a fuel issue, I took the carb to a local guy that rebuilt it for me last year. He put it on his tester and ran fuel through it and it works perfectly. So I reinstalled it and I'm getting fuel, and still nothing. Even if I use ether I dont get a sputter. I'm at a loss. I've had my dad look at it, because he has a whole lifetime of experience with this and he's stumped too.
If you pull the coil wire out of the cap and position it near a ground, are you seeing a spark when you crank it? If so, then check that the rotor is pointing at number one with the piston at TDC compression. Maybe the timing chain slipped?
Yeah I'm definitely getting spark from the coil wire. I dont know how bright/strong its supposed to look, but I put the inductor for the timing light on cylinder 8 as far from the distributor as I can and the spark still sets off the timing light. The issue I have now is that I reset the distributor to TDC when I reinstalled it, so if the timing slipped, would there be any way to test it short of pulling the cover?
Yes. Used a plug in cylinder one until the pressure popped the plug out. Moved it to TDC and the timing mark on the balancer lines up with the 0 degree mark on the timing cover.
I'm fresh out of ideas. If you have spark and fuel, and the spark is occurring on the compression stroke, it should at least try to start. How old is the timing chain? Is it original?
No it's new, rebuilt the engine last year. I really am stumped. I appreciate all the advice and help. If I manage to get this figured out I will be sure to keep everyone informed.
Yes you can. might have to pull a valve cover. Tdc on timing should be compression on #1 cylinder . watching the valves as you hand crank motor helps determine when intake valve begins to open and a cork or finger over #1 spark plug hole pops when compression starts. These simple tests help rule out a jumped chain. Timing light tells you the same. First Verify rotor at #1 at tdc. Based on your description that it ran last season My guess is you could be up to 180 degrees out on distributor timing and rotor position will tell you this . with all the distributor changes my money is on you lost timing by a tooth or two. Its pretty easy to be one tooth off multiply that by dizzy change outs and you have a headache. Been there done that. Back to basics.
The only thing I can tell you is when checking for the compression stroke, it's important to bump the starter a little at a time. If you run the starter until the plug pops out, you can easily over run TDC, and if you continue to turn the crank CW until the mark lines up, you'll be 180* out. That's all I can think of right now.
