Engine won’t start - no obvious reason

[aquifer]

The engine is a 74, stock 1600 dp with a stock 34 pict 3 carburetor and a stock SVDA distributor.

A sudden problem arose after previously running fine. The engine turns over but will not start. Cranks, but no fire, no sputter. I have spark, fuel, compression. Here are more details that might help:

The car hadn’t ran in a while and had bad gas. I drained the gas, took the carb apart and cleaned it up - fuel inlet valve was sticking. Engine fired right up and I drove it around a little bit. Pulled in the garage, shut it off. Next day it fired right up, ran for maybe 3 seconds, and died just like the key had been turned off. No noises, no sputter, just died. Would not restart. I thought of the float valve again, but fuel squirts in from the accelerator pump. Plus, I dumped a bit of gas down the carb just to be sure. It’s not a fuel problem.

The distributor had electronic ignition, but everything inside it was filthy and the pertronix module was loose. I figured that was the problem so I removed the distributor and disassembled it to clean it up. I had another distributor, an SVDA but not exactly the same model number, which has points & condenser. I installed it in the meantime just to get it running. No dice. Still won’t start.

Long story short, as each troubleshooting step failed, I’ve checked for spark, replaced the coil, points, condenser, and spark plugs. The plugs were fouled from the old gas so I thought I was on to something. No dice. Still won’t start.

Once in a while it will backfire while cranking. So I static timed it, good enough that it should start. But nope. It does still backfire though once in a while, so I haven’t ruled out timing. But the rockers are fine, valve gaps are fine.

I must be missing something obvious. Since it wouldn’t start before all the troubleshooting began, and it still won’t start, what am I missing? I’m not a novice, this seems pretty simple to me, but I’m out of ideas.

Any advice, no matter how unlikely, would be appreciated! Thanks
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Parts needed:
Front & rear NOS or used OEM door panels for a '67 in the original Gazelle color (dark tan/light brown).
Also looking for used white headliner pieces, both perforated and non-perforated.

[Max Welton]

Maybe flooded?

Max
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1967 Type-3 Fastback
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[baldessariclan]

Sounds like probably as ignition / timing issue to me, since you are getting an occasional backfire. I'd first double-check on your points condition and gap, and then attempt to static time again. Maybe vary the timing point a little bit at a time from the initial static timed location, until it starts firing more consistently -- doesn't take very much movement for timing to be off enough where it won't fire at all!
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1971 Standard Beetle — fairly stock / driver

baldessariclan -- often in error, never in doubt...

[bsairhead]

If the first distributor was a 009 your probably 90 degrees off.

[OldSchoolVW's]

[baldessariclan]

[aquifer]

Thanks for the suggestions. Brand new points, plugs, condenser, so I don’t think it’s that, but I’m intrigued by the timing idea. Both distributors are SVDA but not the same model numbers. They appear to be identical to me. The vacuum canister is facing the rear which it was on the other one too. I know that’s not definitive for timing, but I think they generally face the rear, so I think the timing is reasonably close. Yet there’s still a backfire once in a while.

Still, the coincidence that both distributors result in the same no-start problem is not very likely. I’m thinking about the backfire. Something isn’t quite right here. I’m going to examine the plug wires more carefully. I got spark when I checked them the first time though. Hmm….

I appreciate all suggestions.
_________________
Parts needed:
Front & rear NOS or used OEM door panels for a '67 in the original Gazelle color (dark tan/light brown).
Also looking for used white headliner pieces, both perforated and non-perforated.

[bsairhead]

I would re eyeball my wires.

[aquifer]

Something I just thought of:

I’m either at TDC of 1 or 3. The rotor is pointing “southwest” which is the plug wire going to #1 so I assumed it’s TDC of #1. But is southwest where #1 should fire? Maybe this distributor is different, and the problem with the other one was truly a coincidence? Maybe the rotor shaft is off 180 degrees and the engine is at TDC of #3 even though the rotor is pointing to #1 wire. I’m grasping at straws here.
_________________
Parts needed:
Front & rear NOS or used OEM door panels for a '67 in the original Gazelle color (dark tan/light brown).
Also looking for used white headliner pieces, both perforated and non-perforated.

[Cusser]

Go back to basics

Spray some aerosol starting fluid into the air cleaner or carburetor throat, try to start, do this a few times. If it runs for a few seconds then quits out, you have a fuel delivery issue, start there. If it won't run at all when you do this, then it's a spark issue, work on that. This is a common first test to help isolate the problem. This is practically an ALWAYS: isolate whether spark or fuel.
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[aquifer]

Ok I found the problem. The two distributors are 180 degrees off from each other. I put it at TDC and popped open the valve covers. Even though the rotor was pointing southwest at the wire going to #1, it was #3 that was at TDC. So I switched the wires and bingo! Fired right up.

I suspect that someone installed the cog on the other distributor wrong and just made the plug wires match. After I switched the wires, TDC of #1 now faces northeast which is probably the correct way. So I truly did have a coincidence here. The problem with the first distributor was that the pertronix was loose, and the plug wires caused this one to be wrong.

I also have a bad plug wire going to #1 so I’ll get a new set. Anyway, mystery solved! Thanks for the ideas, everything helps to narrow down the problem. I needed to dwell more on the backfire and timing, which was the problem.
_________________
Parts needed:
Front & rear NOS or used OEM door panels for a '67 in the original Gazelle color (dark tan/light brown).
Also looking for used white headliner pieces, both perforated and non-perforated.

[bsairhead]

Glad to here you figured it out. Yes the dog can be 180 out. You now know to note the rotor direction from the first distributor matches the next. As long as you have room to time it 'the can' and your plug wires reach it makes no difference. Unless it's an old unit with the #3 mentally challenged.

[ashman40]

Just a follow up for anyone reading this for tips on fixing their own problem.

When you are considering the removal of your distributor and adding a different one in its place... before you remove the old (working?) distributor, manually rotate the crank pulley until the rotor is pointing to the post on the cap where the #1 plug wire is connected. The TDC (or timing) mark on the crank pulley should be close to the case split. You now know your rotor is pointing to the #1 post on the cap and your crank+cam is at the end of the compression stroke for cylinder #1.
Now remove the distributor and install the new one. Making sure the cog at the bottom of the distributor mates properly with the gear down in the case. It only fits one way. Rotate the distributor body until the #1 post notch on the rim of the body is below the rotor tip. Now this notch represents where the #1 plug wire belongs.
Note where the rotor is pointing. This is where the #1 plug wire MUST be placed... even if you disagree. The engine was ready to ignite cylinder #1 when you removed the old distributor and you didn't rotate the crank so it is STILL expecting the distributor to deliver a spark to #1 spark plug. As the one installing the distributor YOU need to make sure to install the wires so the rotor delivers a spark to the #1 spark plug. The remaining wires are installed around the cap in the 1-4-3-2 CW firing order.

If you forgot to manually position the engine at the end of the compression stroke for #1 cylinder you can determine where this is by watching the #1 rocker arms as you rotate the crank pulley CW. Watch the #1 intake valve open and close. Once fully closed you will be at the end of the intake stroke. Rotate the crank CW another 180deg until the timing/TDC mark lines up with the case split. Now you are at the end of the compression stroke for #1.
I'm assuming you did something similar to determine you were at #1 TDC even if the rotor was pointing in the wrong direction?
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AshMan40
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'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!}

[bsairhead]

If the distributor drive is not installed by the book, 'i would say correctly' but it matters not. The can may not allow the lining up of the rotor with the motor on cylinder one compression to the notch on the distributor body. It does not matter. What matters is the rotor position to a cap wire. And of course "zunfolge"1432

[tasb]

SVDA vacuum canisters will/should have a three digit number on the pull arm. This became necessary because at that time all the canisters looked the same and a part number allowed us to tell them apart.
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Roads Scholar
1957 Kombi low mileage 36 hp governor equipped M 178 Slow Drag Winner 2014, 2015, 2018

1965 hardtop Deluxe Microbus owned since 1990 M 620 factory 12 v 1500cc

1961 (October)Single Cab- Road Trip Workhorse

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[aquifer]

[Cusser]

[heimlich]

Using TDC is the best way to set up your distributor. You should not make any assumptions about the drive gearing being installed the correct way.
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[baldessariclan]

[bsairhead]

SW or NE neither. About 20 minutes past the hour looking down if the front of the car was at 12 oclock. So SE.