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Discussion Starter #1 (Edited)
Been away from this board for a couple years as life got in the way. Got divorced, moved, put the car in the garage, kids out of the house etc. I'm back.
Hi everybody!

A couple years ago I put a rebuilt distributor and Pertronix ignition in the car, as well as replaced my ailing TA with a Shankle Sure Start. The car hasn't run right since, and I'm about to go nuts.

Symptoms:
Car blurbles excessively on deceleration, misses and backfires on acceleration, misses and puffs on light acceleration.

FACTS
Old smog pump and stuff is long gone. I have a '74 two piece header, and a stock '77 SPICA.
The car does not have a TA.
It has a Shankle Sure Start with a 27mm projection.
SPICA TA adjuster screw is set so the gap is just over zero. (Reference Locknut was moved by a PO, but I have it adjusted to show six threads on either side of the nut and mount.)

Long arm adjusted for .019 gap.

The car has new NGK BPR7ES plugs.
Pertronix Ignition
Rebuilt diz from Centerline
Timing is adjusted correctly
Recent plug wires
Strong Bosch blue ignition coil
Good compression - 150 to 160

SPICA is adjusted correctly and by the book, with the likely exception of the fuel/air mixture via the cold start solenoid which I can't seem to get right. I'm not completely confident about the reference screw or the TA adjuster screw setting.

This is bizarre, because the car ran better/great with the points and condensors, and a bad TA!

I replaced the plugs twice this month because initially, I was running so rich they fouled and turned black. Plugs are currently tan/white after running around the neighborhood trying to get the mix right.

What am I doing worng?
 

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Try one at a time: a different distributor, and a different TA. The old saw says 90% of fuel problems are in fact ignition. Sometimes proves to be true, sometimes not. If that's all you changed, I'd start with those two just from a troubleshooting perspective.

Andrew
 

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Discussion Starter #3 (Edited)
The distributor is freshly rebuilt from Centerline, and and advances flawlessly. Not sure what else it should do, as it has a solid state ignitor.

The car does not have a TA, as I stated in the OP. It has a Shankle Sure Start.
Thanks for the comment about the ignition system. I will double check it.

EDIT: I guess I could try putting the old diz back in, if I can find it...
 

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"SPICA is adjusted correctly and by the book, with the likely exception of the fuel/air mixture via the cold start solenoid which I can't seem to get right." The "running" mixture is adjusted via the fuel shut-off solenoid, not the cold start solenoid. The cold start solenoid is adjustable, but only effects the enrichment when cranking. Sometimes the cold start plunger can get stuck and cause way rich mixture. A quick way to test cold start solenoid adjustment is to energize it while the engine is at FOT at about a 900rpm idle. When energized, it should drop idle speed, but not stall engine immediately. Burbling on decel can be caused by a faulty micro switch, maladjusted short or long rods, or inoperative fuel shut-off solenoid. Easy test for micro switch operation with a test light. Remove fuel shut-off solenoid and energize to test. Several threads here on adjusting the fuel mixture at the fsos. I just lean em out until they wont rev-up or run, then slowly add more fuel. Then do plug checks. If the car wasn't run for years, have you checked for rusty tank, clogged fuel filter, fuel pressure?
 

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My own experience with Sure Starts is they don't hold settings; they slip. Not a lot of experience, but what I had was not good. Like the TA, they default towards rich. So maybe that's your richness?
Andrew

Now in thinking about it, I wonder if I'm right re the way Sure Starts are sprung, and what the relaxed position is. I don't have on handy to look at.
 

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I'm pretty new to SPICA but the formula sounds to be pointing to a stuck micro-switch which then translates into the dire news that the pump has got to come out. I do know SPICA systems are very touchy when allowed to sit for long periods of time. Mine was like that. I think your ignition solutions have pretty much been exhausted. I have a feeling Wes will confirm this.
 

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I don't know.. Might be .. I was just looking at Wes's manual and he said it had to come out. Page 8 of the salmon colored book I have.
 

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(I hope I'm remembering this correctly)

In the late 1970's, I had a '71 Spider with a Shankle Sure Start and the car had this same problem. I brought the car to the mechanic (he was a well-known senior mechanic from Alfa Romeo, Inc. in Englewood Cliffs, who had retired and started his own shop), who showed me that at full "lean" position, the Sure Start plunger did not extend as far as the plunger of a hot TA, thus the car always ran rich.

We fixed the problem by re-installing a good TA, and then re adjusting the fuel cut-off solenoid and other mechanical adjustments.
 

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Hi there, a couple of idea's. Are your min and max stops set correctly? Since you know your reference screw on the rear of the injection pump has been messed with, I would look at the picture in this thread and see how it compares. Maybe adjust it, but that's kind of the holy grail of "do not touch" things. From there it really sounds like everything needs to get reset to nominal. .019" with long rod disconnected and dummy actuator or sure start installed, adjusting long rod so it doesn't affect the .019", adjust short rod so the throttle plates are just barely closed. Then with a warm car set your running mixture with the fuel cutoff solenoid, I like the 2500 rpm method. After that you can set/test your cold start solenoid and test your microswitch/fuel cutoff solenoid operation.
If you are using a dummy actuator to set .019" make sure that when you put the sure start in that you are indeed back to .019", with the long rod disconnected.

Cheers,
 

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Discussion Starter #12
[email protected]

(I hope I'm remembering this correctly)

In the late 1970's, I had a '71 Spider with a Shankle Sure Start and the car had this same problem. I brought the car to the mechanic (he was a well-known senior mechanic from Alfa Romeo, Inc. in Englewood Cliffs, who had retired and started his own shop), who showed me that at full "lean" position, the Sure Start plunger did not extend as far as the plunger of a hot TA, thus the car always ran rich.

We fixed the problem by re-installing a good TA, and then re adjusting the fuel cut-off solenoid and other mechanical adjustments.
That seems worth looking at, as the car has never run properly with the Shankle installed. I made a dummy TA a while back. I will install it and see what happens.

Looks like rebuilt TA's are $385 with a $75 core fee. Ugh.

"I brought the car to the mechanic... who showed me that at full "lean" position, the Sure Start plunger did not extend as far as the plunger of a hot TA, thus the car always ran rich." I think the Sure Start extension deficit can be accommodated by adjusting the TA screw inside the SPICA. If it does not extend the full depth, seems the TA screw can be brought up to make the difference.
 

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Discussion Starter #13
My own experience with Sure Starts is they don't hold settings; they slip. Not a lot of experience, but what I had was not good. Like the TA, they default towards rich. So maybe that's your richness?
Andrew

Now in thinking about it, I wonder if I'm right re the way Sure Starts are sprung, and what the relaxed position is. I don't have on handy to look at.
The relaxed position on the Sure Start is fully extended. So if it slips, it's set to the engine fully warm position.
 

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Discussion Starter #14 (Edited)
Try one at a time: a different distributor, and a different TA. The old saw says 90% of fuel problems are in fact ignition. Sometimes proves to be true, sometimes not. If that's all you changed, I'd start with those two just from a troubleshooting perspective.

Andrew
Andrew wins with his general diagnosis! "The old saw says 90% of fuel problems are in fact ignition."

My distributor rotor is crashing into the distributor cap. Apparently the rotor is too high - so it is scraping the bottom of the electrodes in the cap. It's not wobbling, it's simply riding too high.

I guess I have the wrong rotor or cap...

The cap is firmly seated and secured to the plate of the diz. The cap seats firmly. There's no excessive play in the shaft.

This is a rebuilt diz that I bought from Centerline couple years ago. The car hasn't run right since I installed it.

What the heck?
 

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Here are the culprits. Rotor is hitting Cap from below.

I don't know why.
maybe mismatched rotor and cap?
or, rebuild back then wasn't so hot and there is play in the shaft?

(you say it never ran right since you got the rebuilt dizzy from centerline.....I'd have thrown it back at them, but now its too late)

there is also this (though yours is not a plex)
https://www.alfabb.com/bb/forums/electrical-chassis-lighting/194269-marelli-plex-rotor-interference-alert.html
 

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Are you sure that the rotor is oriented correctly and is fully seated on the advance weights?

CSS. For info, it anyone is unsure about the adjustment of the CSS, it should be about a quarter inch from the pump casting to the bottom of the CSS.

Microswitch. LOL. Good luck changing a microswitch in-situ.
The microswitch can easily be tested with an ordinary test light connected between the wire to the FCS and ground. Run the engine up to about 3000 rpm and snap the throttle closed. The light should come on, then go off as the engine decels through 1600-1300 rpm and recovers to idle.

Relay crank. If you need to check the relay crank, PM me and I can loan you the jig to check it and set it if necessary.
 

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Discussion Starter #20
Crap.
I was wrong about the distributor cap and rotor colliding. I measured the pieces with a micrometer and there is plenty of space between the top of the rotor and the cap.

Reinstalled, checked timing and the engine still runs like crap above 3500 rpm. It sounds ragged, and when I use my timing gun, the mark on the crank jumps all over the place once the revs get up.

Timing advances normally up to 3500ish, but then starts jumping around all jittery.

Plugs are new.
Wires are six years old but have less than 5k on them.
Same with the cap and rotor.
Diz is rebuilt.
Ignition system is Pertronix.
Coil is Bosch Blue and recent.
Spark is strong.
 
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