Hi friends. I'm running out of ideas after a couple weeks of doing everything I can think of to get this old girl running again.

A little background: Car ran when it went into storage in 2007. I'm the 2nd owner, it's a numbers matching car so I'm going back original, or as close as is reasonable. I pulled off the Edelbrock Performer intake and Q-jet carb (from a 75 Vette, and was running on this car in 2007) and replaced it with the original intake and a factory rebuilt correct number carb I bought many years ago. Before doing anything, since the engine was not rotated for years, I squirted some oil in each cylinder, manually rotated the engine several turns, then used the starter with plugs out to crank around and lube up everything. Of course lubed up the rocker arms, lifters, etc. since the intake and rocker covers were off. Oil change, filled up the filter with oil first, etc. New repro engine wiring harness, replaced plug wires with original repros from LL. New coil, new points and condenser, new plugs, new dist cap and rotor. New fuel pump. New harmonic damper, and verified that the timing mark was in the same place as the old one.

After unsuccessful cranking, I've done a lot of troubleshooting by systematically testing, verifying and eliminating pretty much everything I can think of. Several times. My experience is that problems like these are usually a simple thing, overlooked or missed so I go back to basics and start from zero. Fuel, spark, air...

I've verified that I have fresh fuel through the carb, (accelerator pump squirts fuel, and plugs are wet with fuel) power to the coil and through to the distributor, spark by grounding a spark plug and watching it fire. I've used the white papers kindly supplied by Lars to reinstall and set up the distributor and timing. I found my dist drive gear reversed, but fixed that. Verified TDC with a look at the valves on #1 and verified that the piston is at TDC with a pencil in the spark plug hole. (Many times.) I've rung out the spark plug wires with a multimeter to verify they are all correct. Verified firing order. My distributor and firing tab are in exactly the same position as shown in the pix in Lars' distributor paper. Meter says that points open at exactly the correct time.

Thinking that the oil I squirted in the cylinders may have fouled the plugs, I've sprayed a little ether into the carb, with no success. Plugs are very wet with fuel, but have changed them out, too.

I've blocked open the choke to address the flooding, and done the 'hold the accelerator to the floor while cranking' routine to clear a flooded engine.

What have I missed?

My next step/idea I guess is to swap out the carb. It's a 'factory rebuilt, correct number' Q-jet carb that has not run on the car, and I have a second factory rebuilt 'functional replacement' Q-jet carb that I bought years ago from Ecklers. ( I know the prevailing opinions on 'factory rebuilt carbs. I collected these over a couple of decades, and you don't know what you don't know...until you know it.) Spark plugs and inside the intake is wet with fuel, which is probably from the fact that it won't start, but could be carb-related. Maybe. Thinking that since I have a spare, changing it out should eliminate another possible cause?

Open to ideas, and thanks for the help!

 

You have fuel, spark and air, do you have compression?

 

If it will not light off with ether, and plugs are wet then clearly it's not a fuel issue as much as ignition issue. Plugs are not firing, or not firing right at all.

I suggest getting a spark tester and verify they are firing.

 

Agree if no fire on ether sounds like ignition.
Points ignition?
Verify voltage to coil in start position (12v) and in run position (9v).
Verify spark and spark color under pressure with an inline spark tester.
Ether, to verify ignition is good.
Give it a good squirt too.
Check coil ohms.
Try known good coil.
Fresh plugs.
That should rule out ignition issues.
Only then carb.

 

Hello,
Might the distributor be 180 degrees off???
Regards...

 

Thanks Alan. I've checked #1 TDC with rocker covers off, both valves closed, TDC using a pencil in the cylinder. Lines up with timing mark on damper, too, (so 50/50 chance even if I'm on the wrong stroke.) Used the whistle in the spark plug hole gizmo, too. Several times. So, I don't think so.

However, the darn thing won't crank, so it's either fuel (nope...verified I've got plenty) or spark (nope...verified by grounding a plug but I'll go get a tester) or timing. The distributor is in exactly the same orientation as in the pix in Lars' paper, so its either correct or 180 out.

I did find the dist drive gear out by 180 degrees, but corrected that. But, even if it was done years ago to correct distributor position to clear ignition shielding (aftermarket cam) then it should be close enough that rotating the distributor in place should get close enough to crank.

I may just pull the distributor and walk it around 180 degrees just to rule it out. It's going to be one of those dumb face-palm things when I find it. Just got to do the work...

 

Instead of distributor lined up with #1 at 0 degrees on damper line it up with 12 BTDC. No engine will run with timing at 0 degrees.

 

Sorry I wasn't exact. I set crank at 10 degrees BTDC then indexed the distributor.

 

Well, this is weird. When I disconnect the (+) wire from the coil and run it through a multimeter (to engine ground) I get 10.3V while cranking and 12.6V in run position. That's the opposite of what I expected.

So I checked the starter solenoid connections. "R" terminal is the cloth covered 'yellowish' wire from the coil. Purple wire goes to the "S" terminal. Red wire is connected to the same terminal as the (+) battery cable. Ground cable from the starter housing to the engine, and the black ground wire in the harness is connected to the bellhousing. All as factory and correct according to Doc's laminated schematic drawings.

My engine wiring harness is a new LL repro, (actually the whole car has new harnesses, including the battery cables.) At the coil (+) I have a cloth covered wire from the starter solenoid and a black wire from the fuse block that the schematics say is a resistance wire. If I understand correctly, the black wire should be from the fuse block to provide 9V run voltage and the yellow fabric insulated wire from the solenoid should provide 12V or so while cranking. But, my measured voltages seem to be the opposite. But I don't understand how.

FWIW, I get 12.7V directly across the battery with no load. Maybe the voltage drop is due to the starter being engaged while measuring?

 

Did you do anything to adjust the valves when you put the new intake on? If so are you sure you didn't put in too much preload? A simple compression test will make this known.

You said you got spark on #1, get the tester and check at least 4 or 5 of them. If they are sparking I wouldn't worry too much about your starter or distributor connections.

Don't change out the carb until you know it's not working. Even with a bad, gummed up carb the engine should fire off or at least try to with the ether and fuel that you've tried. Hell, even without a carb on there at all it should ignite fuel in the combustion chambers.

 

Thanks. Did not adjust the valves. I'll pick up the tester tomorrow. Good advice.

The run voltage being higher than the crank voltage is puzzling. I've done a little reading and a possible cause could be a bad starter solenoid. The solenoid should close a contact on start and supply full battery voltage to the coil. Since the crank voltage measures lower than run voltage it looks like it's not sending full voltage. If I don't get spark when I do the test you suggest, this may be the cause.

I do recall changing out the solenoid several years ago and do not remember if the car ran after that. Maybe I got a bad one and never knew. (I was in the middle of changing out every wire, relay, switch, etc. in the car since I HATE chasing electrical problems. It would suck if I did this to myself....)

Again, thanks to all for the advice and guidance. Much appreciated.

 

Sounds like a voltage problem to me.
Suggest unhook both ends of the resistance wire and verify it has resistance with an ohm-meter. Not sure of the spec tho....

All new wire harness....hmmmm. do you have the large engine block ground wire from block to frame around the pass side motor mount?
The points in the distrib actually ground to the distrib, thru the engine block, thru that big ground wire, & back to the neg batt cable.
You could also check the distrib ground with a ohm-meter.

Starter grounds thru there also. Does the starter spin the engine quickly?

You can verify proper spark timing with the spark tool also.(Cam/distributor/phasing/etc)
Set crank to 12*. (Rotor points to #1 wire) Ignition ON. Engine OFF. Move / rotate distrib back -n- forth a inch or so... that should trigger a #1 spark, when you get back to the right 12* setting where it should go off.
(You are just moving the housing...vs the engine).