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Discussion Starter #1
My "rebuilt" engine (2 Liter + Spica) seems to be burning too rich. Smells like gas a bit and plugs were all black... I went for a 400 mile trip and here are the plugs.
Is there a problem ?
Why are #1-4 brown and 2-3 black-sooty ?
What should I do ?
Local french alfa people (know nothing about SPICA) seem to say that I should keep the SPICA running rich. it functions better than way .... ??
 

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Well, you'll (almost) never burn up a piston or valve with a rich engine.

That aside, 2 & 3 certainly do look more than a bit fat.

Are they gapped properly?
Is the valve lash set correctly, or at least equally across all 4 cylinders?

And, just at a reach, do you happen to have the vac lines on #1 and #4 for brake and crank ventilation? (this would explain why those two are leaner than the others as thre airflow is slightly different)

The closeup of #3 shows something goofy going on at the electrode, or is that a bunny turd that got stuck there? (might just need new plugs :shrug: )
 

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Discussion Starter #3
Rich and unbalanced

Yes there is a weird thing growing on spark 3 ... I did put new ones in place of course.

As for valve lash I have no clue.. I did not do the job....

For the vac lines here is a picture. i think all is right. I took off the oil crank vent thingy since the picture....

I am worried about the uneven burning....

Also how yellow or black should my plugs be.. Should I aim for having them all brown with no soot at all ?
 

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do you have the org air box?
if so I would start there.
also a plug with a bigger electrode will hold up better with rich mix.
the tiny electrode work fine in a computer controled car where the mix is perfect. but in a car with where the mix is not so good they tend to get too dirty to work right.

you might try swaping injectors as see if it followes that. if not I would say the spica might be out some. and other then sending it to wes I would just run it that way.

but the rich guys could be leaky injectors. if so it is easy to find used injectors.
 

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All of the plugs should be that nice brown color. The SPICA does NOT have to run rich to run right. If your mechanic is telling you that, find a new one. If you are in a place that doesn't have experience with SPICA buy Wes Ingrams book and follow it as the one true light. There is a reason he is considered the guru of SPICA!
In my experience the bosch plugs start turning that color if you are burning oil. This is usually from the valve seals. I think that the factory ones are made of paper mache or something:mad:
If the oil consumption has picked up, this might be the case. However, before I went chasing that rainbow, I would get a hold of a manometer or other airflow gauge and make sure that the SPICA is all pulling the same amount of air.
Next, try a different type of plug. I have had good experience with the NGK BP7ES, but everybody has a favorite.
If the problem still persists, you will probably reach a point where you will have to decide how far you want to go......
Good Luck:)
 

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Discussion Starter #6
Rich

No I dont have the original box.. PO changed that years ago.
I do have Wes's book. Read it about 5 times ! I actualy visited him in WA last year. Great setup he has...
I will try following the book to a T but I need to get better organized (protractor etc...) to do it right....
SPICA was done by Wes years ago. My polish workers took engine apart last year. I visited them once to find Spica gas hoses not in place and loads of dust on engine and Spica... I question wether job was done right/cleanly... who knows. Might be something else. I will try changing injectors around. I assume the injector is just the last fitting on the engine block (?)

As far as the oil consumpion, engine was redone. It leaks a bit of oil and was low when I first took it out. Dont think it has eaten any additional oil since.. Will check.
Manometer.. ? not sure where to get a hold of one but will try asking a friend who works for a tool company. Whould i try that at a specific RPM ?
 

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Manometers are only to be used at idle!!! If you rev the engine at all the mercury will be sucked out of the tubes and you will be very sad:(
Most motorcycle shops have these, or you could use an airflow meter like a Unisyn (IAP has them) or even better, a motometer ( http://www.racetep.com/weberX.html#websynch). Although $45 is a bunch to shell out for a tool you will use once, there is no better way to be SURE that airflow is even.
 

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Sorry for the double post. I was reading the reply and it occured to me that I haven't asked if the car has sat for an extended period? If so, the seals may have dried or "acquired" flat spots. Sometimes it is good to put some marvel mystery oil in the crankcase and about a teaspoon in the cylinder via the sparkplug well (after the removal of the plug of course) to help condition the seals and gaskets after an extended period of inactivity:)

Also, if the rebuild was not sanitary or done with care, the car could easily be burning oil. However, as I said earlier the oil consumption should be one of the last causes to be investigated after all others are ruled out.

Be methodical and look at each system. Have you checked the plug wire resistance to make sure they are all the same? Checked the cap for pits in the #2-3 terminals? Plug gap? Done a compression test? (If you have any doubt about the rebuild that would be a good place to start) I also agree that the stock airbox is the way to go if you still have it. You are losing power and economy with the lack of a cold air snorkel (even if it sounds good).

Hope this helps!
 

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... I will try changing injectors around. I assume the injector is just the last fitting on the engine block (?)
No, it's not. Remove the hard line at the union I've pointed to in the picture. If you need some injectors, I can probably scrounge some up for you. I can't promise they'll work, though. :eek:

Many years ago, I took the ones from my Alfetta to a VW guy for cleaning. You may just go ahead and do that anyway.
 

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Good responses in this post, could add, unless you are running an electronic ignition system, you should use a conventional plug as previously stated, I recommend the Bosch Super-Copper Core, over here they are cheap. One test: get the car all warmed up on a drive and then disconnect the breather hose coming from the valve cover over to/at the oil seperator with the car running and rev it up, see what comes out of the hose, you're looking for excessive blow-by. Have you cleaned the oil seperator? It designed to funnel blow-by oil back to the crankcase but after thirty plus year it could be full of gunk and malfunctioning, remember at the bottom of the oil seperator is a tube that vents to the airbox, check out the inside of the airbox. Also I'd check to make sure all the exhaust manifold nut a totally snug tight, say they were not tight on the 2-3 branch exhaust manifold, it would diminsh the breathing for the combustion process. I'd say the brown color on your plugs is correct and indicates a good mixture. Too lean can kill a motor fast, too rich will kill it slowly. Wes says the injectors rarely fail, but who knows?
 
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