[T3] up and Running!

Jim Adney jadney at vwtype3.org
Wed Sep 30 07:33:30 PDT 2020

On 29 Sep 2020 at 20:36, Keith Park wrote:

> Another strange anomaly too.  I switched off the Mark 10 to see if
> there was a difference that might indicate an ignition issue, that
> really didn't change things much. But when I switched it back on, it
> didn't want to start, until I switched if off again. and once running
> if I switched to the electronic ignition it would die.. 

I like having the switch on the Mark 10B, because it allows me to switch back 
and forth effortlessly, even while the engine is running. Unfortunately, that 
feature is also the Mark 10B's weakness, as the switch contacts tend to 
oxidize over time and stop conducting well. I find that I need to "exercise" the 
switch a few times to get good contact. I had trouble with this on the way 
back from the AZ Invasion, but finally I just exercised it a few times every 
time we filled up with gas. After doing that, I had no more problems.  

> Once it cooled down completely I started it up and switched over to the
> Mark 10 and ir kept running.   !!??

You exercised the switch contacts and cleaned them up. That's probably all 
it needed after sitting while you rebuilt the engine.

> Ive left it on the kettering system for now to eliminate any involvement
> of the Mark 10 with the original missing issue but Im starting to wonder
> If I have a sticky injector?  I did have a leaker when I put it all back
> together as it sat 3 months and that didn't surprise me (and it did seal
> back up again)
> But how common is a KNOWN sticky injector, one that sticks SHUT?

Even if the pintle moves, the injector passages could be blocked by dried 

> The problem seems to get better the more that I drive it or the warmer
> the engine gets. I do have the mixture tweaked just a bit richer and
> after driving it last night And having it run perfectly even after some
> missing earlier in the day I set the mixture back closer to the set
> point and it was missing again this morning.  Drat! 

I'd add some SeaFoam to the gas, then drive the car and let it clean up the 
system. Don't worry too much about getting your tuning just right until 
everything is completely clean and free-flowing. Otherwise, you'll just be 
chasing your tail for nothing. For now, try to keep it slightly on the rich side, 
but lean, on light load, should not be a problem.

Check your ignition HV parts for problems. Check the SP connectors and 
inspect the cap, inside and out. Stick with genuine Bosch parts. A continuing 
miss could be an open SP connector, a tracked cap or coil nose, or a rotor 
that is arcing thru to the dist shaft.

Yeah, it's nice to be able to pull and replace a Type 4 pushrod tube without 
taking much apart.

Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA

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