Trouble starting '71; have fuel, spark, engine cranks

[johnnyb]

Thanks Visionaut and Hans,  I think I see your point about the mark on the dizzy housing.  I definitely appreciate all the advice, it's the first car I've worked on with points, and I've never removed a distributor until this week, so I don't mind being called out on my work!  

 

    I've got a bunch of items to double-check or adjust from this post.  I'm off of work this week while my kids are on school break, but also in the middle of remodeling my master bath.  I was hoping to get the car running well enough to bomb around town, trips to the hardware store, etc.  I'm sneaking in working on the car when I have breaks from the remodeling, but I'll report back what I've done.  

 

    Thanks! 

    John

[eviction_party]

On 2/20/2023 at 9:11 AM, johnnyb said:

On a related note, are you Ian?  I think I recognize your car from your avatar.  My (now 8 year old) son and I may have met you at the Los Gatos Neue Klasse & Kaffe back in June.  I had just taken my steering box and tie rods off my car the night before, and so I didn't bring mine to that meet.  I finally brought it to the January meet with my older son, but didn't see you at that one.  Glad to see another San Jose '02!

haha, good memory! I think I do remember meeting you then. There’s quite a few 02s in San Jose. 
 

Interesting to think about why your points might’ve closed up so quickly. Points gap decreases over time from the cam follower wearing down, but that usually (conveniently!) coincides with oil changes. The other thing that can decrease the points gap is corrosion/buildup on the contact points themselves from arcing caused by a bad condenser — this has happened to me. 

PM me, maybe I can stop by sometime and lend a few spare parts

[johnnyb]

I've been going through the suggestions in this thread, and one of the suggestions was to check the carb's float setting.  Since my Weber 32/36 has plastic floats, my setting should be 35mm with the floats closed, but I'm finding conflicting information about the floats open setting.  Pierce Manifolds says it should be 51mm (see attached image), but the bowl in the carburetor is only 47mm deep!  I have a photocopied chapter (7) of a Weber carburetor manual that says the stroke (difference between the two float positions) should be 11mm.  If 35mm is the floats closed position, this means my open position should be 46mm.  This is just shy of the bottom of the float bowl.  

    Should it make sense that the floats open position should be this close to the bottom of the bowl, and which should I use?  From Tom's pictures of his homemade float adjustment gages (brass floats) in this thread, it looks like he's using the 11mm (0.433") method. 

 

[cda951]

Did you ever re-check dwell or re-set the ignition timing? My read of the situation is that the no-start occurred after adjusting the point gap, though I might have missed something. Adjusting dwell affects ignition timing, but adjusting ignition timing does not affect dwell.

 

It could be that your point-gap adjustment affected the timing enough to cause a no-start, even if there is actual spark at the plugs. Though I will say that in this case you will often get pops and attempts to fire . . . . 

Edited February 24, 2023 by cda951

[johnnyb]

I've checked the static timing (twice!), and am pretty certain it's set up correctly now.  With the camshaft line indicating TDC for the #1 piston, and the line next to OT in the bellhousing viewport, the rotor points at the lead to the #1 spark plug. I connected my test light from ground to the negative lead on the coil primary, and rotated the distributor so the light shines just as the rotor is aligning with the #1 plug wire.  

 

   I did notice my points gap was at 0.022" tonight, so I set it back to 0.016".  I'm guessing it opened up when I tightened the screw after adjusting it last time.  This time I checked it again afterwards, so I'm hoping this did the trick and it will start.  Unfortuntately, it's now after midnight, so I'll wait until morning to fire it up.  

 

   I've jumpered out the (in my case superfluous) bypass resistor by connecting both ring lug wires together with a bolt and several wraps of electrical tape.  If I understand this correctly, it will give me more voltage to the coil AFTER starting, but won't have any impact to the voltage while the starter is engaged (since the starter solenoid takes the bypass resistor out of the equation while starting). 

 

   I've checked (and adjusted) my carb float settings- I actually only ended up changing the open position from 37mm to 46mm.  I'm not sure what this will do- I'm ordering a book on Weber tuning, as the carb is still a mystery to me.  Perhaps I shouldn't have changed it, but it bothered me that it didn't match any of the correct settings I've come across for this carb.  

 

   The one thing that was suggested that I haven't looked into is vacuum leaks, as I'm not sure how to go about that yet.  I've done some reading on the FAQ, but haven't tried anything yet (bypassing the brake booster/check valve, smoke testing).  

 

   Wish my luck starting it up tomorrow!  Thanks to everyone for the suggestions and advice! 

 

    John B.

[Hans]

Resetting gap means having to reset timing.

Are you measuring float level with top vertical? With or without gasket?

[johnnyb]

@Hans- I follow what you're saying about having to reset timing, but that has to be done when the engine is running, and I haven't been able to get it going, so for now, I've only set the static timing.  As for the floats, I am measuring it with the carb top pointed vertically so the floats are hanging (and the 35mm position set when the float tab is touching, but not pushing in the ball).  I'm doing this with the gasket installed per the Pierce manifold guidance (I've heard conflicting info on whether this should be the case or not).  

 

So an update: This morning the car started right up (after a couple of seconds of cranking to refill the carb bowl).  It ran a bit rough, but this was expected since it was set for static timing.  However, the engine died before I could get around to the distributor to try advancing it.  I tried to start it again, but no joy- it just cranks.  I pulled the carb top off to see how the level in the bowl was, and it looked about the same as it did when I started this thread (it should- I kept the same 35mm float position).  Opening the choke and throttle valves, I see some puddling up of fuel in the intake manifold under the carburetor.  So we pulled the spark plugs, and all four of them are wet, with the plug gap bridged by fuel drops.  

 

    I don't have experience adjusting carbs, so I'm purchasing a book from Pierce Manifolds, and figured I'm due for new gaskets at least, if not a full rebuild kit.  I was also planning to order the jets per the C.D.iesel precription.  Here's my current setup: 

• Primary 
  • idle 55
  • main 140
  • air correction 155
• Secondary 
  • idle 50
  • main 135
  • air correction 160

   In the meantime, I've found this thread , which is at least partially copied from this setup guide.   I'll try to start working through these. 

 

   Also attaching some fun photos for your viewing pleasure. 

 

    Thanks, 

    John B

[johnnyb]

I forgot to mention- I pulled the vacuum pod off the dizzy, and it does move when I suck on the hose.  It works also now that I've reinstalled it on the dizzy, so I guess it was just binding a bit.  I still have the vacuum on the manifold plugged while I'm running static timing. 

 

    Thanks, 

    John

[eviction_party]

50 minutes ago, johnnyb said:

Opening the choke and throttle valves, I see some puddling up of fuel in the intake manifold under the carburetor.  So we pulled the spark plugs, and all four of them are wet, with the plug gap bridged by fuel drops.

 

This sounds like a needle valve that isn't sealing. If you haven't cleaned the carb, there could be some junk in there preventing a seal, or the seat is worn and needs replacing. Easy fix to try!

Edited February 24, 2023 by eviction_party

[Son of Marty]

How soon are you pushing the choke in/off?

[adawil2002]

Why are those wires on top of the coil electrical taped?

 

I had a similar issue with my 1968 1600. Fuel, air spark were all there & the car still wouldn't start.
Turned out one of the wires from the coil had gotten pinched & was grounding, shorting the spark.

$75 to have my mechanic diagnose & fix.

[visionaut]

6 minutes ago, adawil2002 said:

Why are those wires on top of the coil electrical taped?

 

11 hours ago, johnnyb said:

I've jumpered out the (in my case superfluous) bypass resistor by connecting both ring lug wires together with a bolt and several wraps of electrical tape.

 

[johnnyb]

2 hours ago, Son of Marty said:

How soon are you pushing the choke in/off?

Today I never pushed it in, I left the choke closed (knob pulled out).  It didn't stay running for more than 10 seconds or so.  Normally, I'd leave it choked for a minute or so (less when it's warm out), then progressively push it in until the water temperature comes up.  I've never had a manual choke before, so feel free to tell me I'm doing it wrong.  

[Hans]

Changing the point gap changes the timing. Can't say by how much 022 to 016, or whether thats your problem. Were the plugs dry before you tried this time? Maybe flooded? Were the #1 valves closed at your TDC?

[johnnyb]

I've been busy with work and home projects, but got some time to play with the 02 tonight.  Replaced the plastic floats with new brass ones in the Weber, replaced the needle vale and gasket between the two halves, measured valve clearances (all around 0.008" clearance- not compressing the valves when piston is at TDC), and got the car to fire right up tonight!  I immediately pushed the choke in just a bit (previously I would wait until the engine was warmer), then took the car for a warmup drive.  I measured the dwell at 55 degrees, stopped the engine and decreased the points gap (to 0.012").  With no choke, and a bit of throttle, the car restarted, and I measured the dwell at 57 degrees.  With the timing light, I can see the "Z" and the BB in the bellhousing hole.  

 

Now, the bad news.  Compression measures 95-110 across all four cylinders.  I'm pretty sure I've read that below 110 you should be considering a rebuild.  Sigh...  hopefully I can push that out a bit, even as is, I enjoy running around town in this car!  

 

   Thank you all for your advice and suggestions.  I don't know that I believe I found a single root cause, but I now know how to adjust timing (I still need to play with measuring the advance with the Innova timing light), and have a basic understanding of the various jets and adjustments on the Weber. (including how to use the manual choke).  What a fun little car. 

 

    -John

Edited March 4, 2023 by johnnyb