[goats]

Gents,

As reported previously we ended up getting all major oil leaks fixed, steering box seal done per Roadtrip's write-up (except that I could only withdraw the shaft rod up about 2 inches, more than enough to swap the rock hard seal out). Spica gap is 0.019 ; long rod in; short rod in, manometer readings are really close on all 4 sides (about an inch of mercury delta between the two pairs), etc. Mixture seems good, perhaps a smidgen rich but that's OK by me on a fresh motor -- its not rich enough that I can smell it.

Car is stock 74 GTV refreshed with rings and rod bearings due to a leaky Spica a few years ago. Cams are 10548's, set to about 105 ish degrees. Valve clearances are also good at a hair less than 20 thou. SPica is Wes Ingram HP pump that he knew I was running stock pistons and euro cams. Distributor timing is set to about 4 degrees advanced from stock mark. I get close with M mark at 5K RPM but doesn't quite make it there. Dwell gap set right on the button with feeler gauge.

Car dies when coming to a stop. Its dangerous and annoying to have to do the complete key turn off, and turn on, when the light is green in front of me and I have SoCal motorists on my tail. I can not get much out of the idle adjustment screw (new O-ring installed). Idle just seems low and hence, car dies at stopsigns and stoplights.

Second, there is a momentary miss under hard accel. It misses two beats on the way up (like a missing spark on one rev) then goes great.

Seeking advice about setting timing (should I advance it some more?) -- seems to help the idle speed and levels it out ; what other suggestions to get the idle up and stable?

Thanks ! Car is beginning to take shape and hopefully can be a daily driver (once I get this idle thing solved - its really dangerous to have that where I live)

 

[MCain]

I believe you have a SPICA issue. Have you gone through Wes Ingram's manual? Good stuff on fuel pressure and further adjustments.

I recently re attached the fuel pressure warning light the P.O. disconnected, working through diagnosis of fuel pressure problems, or not. (Bad sensor)

Good luck, Spica is wonderful when dialed in.

 

[goats]

Yes, followed Wes' manual to the letter

Indeed I did and set the mixture using a gas analyzer. The gap is right at 0.019" and everything seems kosher. Fuel pressure light works great, filters have been replaced, etc etc.

 

[Alfajay]

Distributor timing is set to about 4 degrees advanced from stock mark. I get close with M mark at 5K RPM but doesn't quite make it there. ...Seeking advice about setting timing (should I advance it some more?) -- seems to help the idle speed and levels it out ; what other suggestions to get the idle up and stable?

I'm a little confused about where your timing is now. The first sentence above says it is "about 4 degrees advanced from stock mark", but the second sentence says it "get close with M mark at 5K RPM but doesn't quite make it there".

I'm guessing you're saying that at idle it is 4 degrees advanced from the "F" mark on the pulley, but at 5,000 rpm it is still short of the "M" mark.

You have my permission to try advancing it some more. Alfa was pretty conservative in its high rpm advance settings, especially on mid 1970's cars, when it was struggling to meet emissions standards. So advancing it a few degrees past the "M" mark should not be that radical. As long as it doesn't knock, and as long as it starts OK, you should be fine. And hopefully this will solve your stalling problem.

I can't comment on your spica settings - I'm a Weber kind of a guy for exactly the reasons this thread is about.

 

[goats]

Jay close. Its a little bit advanced (long or late, beyond mark) from P (idle timing) and a little retarded (short or early, not quite reaching) from M at 5K rpm. Starting is tough for sure.

 

[144]

1. Make sure you don't have any vacuum leaks from the brake booster hose.
2. Disconnect the Fuel Cutoff Solenoid to make sure a badly adjusted microswitch isn't at fault.
3. Has the relay crank and Idle/WOT screws been set with the factory tool?
4. Have you confirmed that all four little idle air hoses are clear?
5. Have you tried removing the idle rubber o-ring altogether?
6. Have you timed the injection pump to TDC -70 deg on the power stroke of the #4 cylinder?
7. If you hold the throttle slightly open with your foot, does that make it idle?

 

[goats]

Thanks John

1. Pretty sure no vacuum leaks but will re-confirm tonight
2. Will try this
3. Yes
4. Yes
5. No; trying to decide if its timing related vs air flow related
6. Yes for certain
7. Yes but it raises obviously the RPM -- idle seems to settle in after everything is warm around 650 rpm.....

 

[Alfajay]

Starting is tough for sure.

Hmm. But is starting tough because the ignition is advanced too far, or just because it's a Spica? If the former, it will crank slowly, as the advanced spark occasionally fires and pushes the crankshaft backwards. If the latter, it will crank quickly, but just not catch.

If your starting problem is related to Spica, advancing it a bit more may not aggravate starting and may improve the idle speed.

 

[144]

1. Is the stalling problem only evident with the engine at full operating temp, during warm-up, or both? 650 rpm hot idle is within spec. That's what my car idles at.

2. Is the injection pump a 74 model? Did you shim the T/A to put it back spec for cold running, assuming it's a 29/31mm extension T/A?

3. Does starting fluid greatly aid initial firing of the engine?

4. How many turns-in is the FCS set at? Is it at least 9 1/2? What color are the spark plugs? Almost sounds like it could be too-lean. When you rev it statically, is there just a slight hesitation, or does it sound "fluffy" when goosed? Any detonation when under high load accel?

 

[goats]

mostly warm

John it is mostly when its warm. Cold start always takes a few tries ; I let the fuel pump run while I attach the seat belt, then turn over, it catches and dies, key off-to-start again, it catches, idles rough and sometimes dies and sometines settles into a nice idle, third time key off-to-start always idles nice.

SPICA is A 74 255 by Wes

Yes TA is shimmed to 29 mm.

Never tried starting fluid

I think I am definitely close to 9 1/2 turns. Set mixture with an exhaust gas analyzer per Wes' manual. Getting on the go pedal it seems to pull pretty well but maybe not as sharp as it could be.

Where would you set iginition timing? Straight up stock with idle at ?5? ATDC ('F" mark?) and let 5K "M " mark fall where it may? or other way around?

Thanks bob

 

[144]

I set my engine at TDC. I do have a Petronix on it. Best thing since sliced bread. I highly recommend it. Points were a major PIA, exhibiting erratic reliability with weather changes.

I assume you've looked inside the distributor cap for evidence of cracks and carbon tracks?

T/A should be shimmed to 27mm at 175F. If shimmed to 29mm, your cold running enrichment will be a bit lean (injection pump thinks engine is warmer than it really is).

My rule of thumb . . . a 31mm extension T/A is shimmed with two washers (about 4mm total thickness) and with a 29mm extension T/A, I use one washer (about 2mm).

 

[goats]

Plugs in Order -- 4 - 2 -- 3 -- 1

2 is far richer than any of the others...... hmmmm

Sorry about the crap photos. I think you can see the color (I hope)

 

[Alfajay]

Where would you set iginition timing? Straight up stock with idle at ?5? ATDC ('F" mark?) and let 5K "M " mark fall where it may? or other way around?

I'd do it the other way around. That is, set it to fire on the "M" mark at 5K rpm, and let the advance at idle fall where it may. Unless this leads to the sort of cranking during starting I described in post #8 you should be fine.

 

[144]

The electrodes look kinda white? I think that might indicate more of a lean mixture.

BTW, Bob, got the base back today. Thanks.

 

[ljayr]

2 is far richer than any of the others...... hmmmm

Plugs 1 & 4 are lean. I would agree plug 2 is rich.

When is the last time you had the injectors cleaned and rebuilt?

 

[Stooie]

Goats:

I'm confused by your post #5.

F is the idle timing mark, about 6 degrees After TDC
P is TDC
M is the 5,000 rpm timing mark, about 33 degrees before TDC

The total centrifugal advance (from F to P) should be 39 degrees.

If you have advanced your idle timing so it approaches P, your timing at 5,000 rpm should be advancing beyond the M mark. If it's not, the first place I'd look is to make sure your centrifugal advance is working properly.

Separate from that I would definitely do the experiment of removing the o-ring in the idle circuit and see if that affects idle speed.

Good luck and don't give up. A well sorted SPICA system is wonderful.

 

[jrichter]

First I wondered if your cold start solenoid was stuck and the fuel cut of was turned lean to compensate but when you showed the spark plugs I don't think that is your issue.

I would definitely have the injectors out and clean them.

I did this a while ago and posted a few pictures of it for reference.

http://www.alfabb.com/bb/forums/carburetors-fuel-injection-air-intake/197613-spica-fuel-injectors.html



Bit OT:
Does anyone know the function of the solid washer with the VERY small hole in it? It can be seen in the last image of my old post. Is all fuel going through that hole?


I second Bob. A well sorted spica is a joy to drive.

/Jens

 

[ljayr]

Does anyone know the function of the solid washer with the VERY small hole in it? It can be seen in the last image of my old post. Is all fuel going through that hole?

Typically when a small orifice is used in fuel injection systems it is meant to eliminate or reduce pulsations in the system.

 

[goats]

Making some progress

I think the mixture was set about 1 turn too lean on the solenoid. Everything else checked out OK -- for now!

I do have a spare set of injectors and an ultrasonic cleaner, but no real good way to test them other than do maintenance then put em back in to see if OK -- I have a PM out to a local member (the gentleman who did that referenced write up) to see if he has his test fixture still---

stay 'tuned' for more as it progresses! HA!
bob

 

[Stooie]

Bob:

You might check with an independent shop that works on Mercedes diesels; they may be able to check your injectors.

Good luck!