Spitfire want start and I'm stumped.

I have a 72 spitfire that was running great, now I cannot get it to start and I am baffled as to why. It has fuel spark and compression. Nothing was changed between starting and not starting, but in the process of attempting a diagnosis I have gone through several things. The carb has been cleaned and rebuilt, new points and gap set. New coil, bypassed the ballast resistor and powered straight from the battery (to rule out any bad wires). 120 psi on all the cylinders. Tested spark at every plug. The static timing looks good, all the valve lash are within spec. Even with starting fluid the best I can get is one "puff" out of it but won't run for even a second.

Out of ideas where to look next. Any thoughts would be appreciated.

For best results, give us a timeline... Was the carb rebuilt as a result of the no-start? Plug wires in correct order?

The order in which things were done could help, but given that it didn't start, and now it's got a freshly rebuilt carburetor and other changes... There are now more differences between running and its current state than there were between running and the first no-start...

120 psi sounds low to me. That was peak pressure after cranking with the throttle wide open? Not that I expect it suddenly dropped a bunch of compression while it was parked one night, but marginal things stack up...

Everything listed was changed because it would not start. Points first, checked spark, everything looked OK but didn't work. Thought maybe it was a fuel issue. Has fresh gas. Plugs were wet so maybe it was flooding, set carb to spec, no go. Got a rebuild kit, pulled it off and rebuilt it. Still didn't work. Thought maybe the spark was too weak, bought a new coil. Still didn't work. Check compression, reads peak 120+/- 3psi on all cylinders, but it's not running so cold motor and stock single tiny carb throat it needs to pull through. Adjusted valves because I was running out of ideas... There were a lot of variables that were checked, but the only thing that has been significantly changed is the carb. When checking the ignition everything is within spec and I can pull the plugs and see them spark. I would hope that even if the carb is terribly out of tune, I could use some starting fluid and get something to happen.

I have done all of these things before as routine maintenance, independently of this no start event, so I'm not without experience. But I do feel like I'm blind right now because I can't get any improvement on my situation.

Ignition 180* out of time?

Muffler plugged? Have you put brand new plugs in? Is the oil over full, gassy smelling? Has the car set for a long time?

If you haven't got it started in 10 min you never will.

I'll take the Spitwad off your hands when you are ready to give up.

Can't have you banging your head on old British junk!

Be sure the gas tank is full so I can make it home!

Checked for good grounds?

Linky

Ignition condenser? They've been known to fail without warning.

I'm going to double check the ignition timing with a rod in the cylinder and not the marks on the front of the motor. I will clean the grounds and then I'll pull and check the condenser. The plugs are new and the gap was checked. No gas smell in the oil. Car was sitting for a week between last running and driving then not starting. Thanks everyone.

I have heard of rotor buttons failing also but you have a good hot spark. Curiouser and...

Do your points spark? Sounds like a points or condenser issue to me.

My money is on condenser

Also check out the coil wire when installed properly. May be grounding out.

Also, is the coil still getting power in run, or only in crank?

Dashpot stuck?

TR7 wrote: then I'll pull and check the condenser.

Not sure how you would check it. Just replace it. In fact, you mentioned in your first post you replaced the points with a new set. Usually a condenser is included. Did you replace it at that time?

Noticed you said plugs were wet, bad distributor cap? New rotor and wires?

The problem is now that you've thrown a bunch of stuff at it, you'll never know what the original issue is. Start at the beginning, using fluid to bypass the fuel system. Get it running on that before proceeding.

Now that you've had the wires off, the first thing I'd check is the order. 1-3-4-2 counterclockwise.

I'll repeat, counter clockwise.

In reply to MDJeepGuy:

And #1 at TDC of the compression stroke (both valves closed), not the exhaust stroke (180 out).

I can't remember but won't a bad condenser result in no spark?

How old is the gas? Granted the fluid should have at least made it start.

Wet plugs obviously mean the plugs are not firing when they should. So the first place I'd be looking are the things that cause this; old gas, valve timing is out (chain jumped a tooth), dwell etc.

I think 'TR7' is MIA

Ignition timing is set, coil has power while cranking, and I have tried wiring the positive directly to the battery keeping the ground on the distributor. It's not 180 out and the firing order is correct. It's getting spark at the points. Dashpot isn't stuck, moves freely. Gas is fresh, I have also drained the float bowl and tried running on only starter fluid. Didn't check cam timing yet. Points have been gapped, but I've never checked dwell on a non-running motor, I will have to look that up. A new points/cap/rotor/condenser/wire set is on order so when they come in I will give those a shot. Will also try to get some video to post here, maybe that will help.

The only thing I can think of is the timing might have "jumped" somehow. You're getting spark, but it's happening at the wrong time for the engine to actually fire. Pull the valve cover and make sure the #1 valves are closed at the TDC mark.

It is a timing chain motor, entirely possible the cam timing jumped if the chain is loose. How many degrees can you turn the crank back and forth without moving the distributor rotor? Shouldn't be more than a few degrees. Since you've messed with the distributor you'll need to pull the cover and check the timing marks to see if it jumped.

The replacement rotors we were getting for a while were dodgy (and may still be). I'd pull all of the plugs and make certain each one is sparking. If so, then I'd suspect ignition timing. In addition to the cam, the distributor advance may be off. Check the vacuum unit (if still there) and the advance springs/weights. An advance spring may have broken or slipped off it's post, or the weights may be stuck.

Another thing to look at, you can have spark at the plugs and have that spark be weak enough the engine won't start, I've had that one kick my ass before. Spark at the plug should be blue/white (not yellow) and you should be able to stick a screwdriver in the plug boot and draw sparks at least 1/4" long.