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Discussion Starter #1
My engine has just been rebuilt and im trying to start it for the first time. The timing seems way off and will not start just an occasional POP :eek:!! Im very weak in this area. I located tdc on number one but my distributor is facing number 3?? Can someone give me a detailed description on how to correct this.
THANK YOU
GREGG
 

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If #1 is at TDC on the compression stroke, the rotor should point to #1 at about 2 o'clock. It is possible in many engines to put the distributor in 180 degrees off. Try pulling the distributor out an inch and turning the rotor until it falls into the slot in the correct place. The bottom of the shaft is slotted, so it can fit in only two ways, correct or 180 degrees off. If this doesn't work, the oil pump may be 180 degrees off. If that is the case, the easiest, if not purest, solution is to move the wires on the distributor cap so the correct plug fires at the correct time.
 

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You sure its at TDC on the compression stroke?
It can be at the top of the exhaust stroke and still have the marks line up, but the end result is the dizzy will appear to be 180 degrees out.

If you can't determine if its on compression stroke, pull the cam cover.
The intake and exhaust cam lobes should point outward.

What model year are we talking about anyway?
If it's an 82~89, click the diagnostics link in my signature block to get some good info and pix on setting up that particular ignition.
 

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You really need to start at square one with the timing.
Pull off the cam cover and rotate the motor clockwise (looking at the front of it ) until the lobes of both cams are pointing towards the outside of the car. There are marks on the cams and the front caps which should line up when you are at top dead center on the crank. Check the timing pointer on the crank pully to see that it lines up with the 'P' mark on the pulley.
Now look at your dist. rotor and see where it is pointing. This should be #1 plug. If not you can move #1 wire there and change the others to their right place. 1342 clockwise rotation.
The slot on the bottom of the dist. is offset so it will only go in one way, but check to see that the dist. is all of the way into the front cover and the drive is seated properly.
 
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Gregg,

Sometimes these seasoned Alfisti can make it seem so easy and straight forward.

It is.

However, those of use that don't have the experience often don't understand the simple step by step nature due to not having experienced it before. I haven't retimed an engine, but am very interested to learn to do so.

Who did the rebuild?

My suggestion is to post your location in the top right (by editing your personal information) and adding your model vehicle with your signature. This helps us all understand the nature of the topic being discussed.

Perhaps someone in your area will come lend you hand and teach you something. Truly detailed discriptions are found in manuals. After reading one (or more) manuals and studying you vehicle, a friend with experience can help you fill the holes in your understanding - in probably an hour or two.

Hoping you get it timed to your liking,

Don
 

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If it has just the occasionall pop then you probably have the plugs wired incorrectly. Depending on the model, Alfa has the distributor fixed so you cannot tamper with it (can't loosen the clamp on the bottom of the distributor to twist the distributor while it is in place). Leave it that way until all else fails. Follow the proceedures above to get # 1 on TDC and then check the gear mesh of the distributof to get the distributor rotor pointing at a contact inside the dist. cap. That will be your # 1 plug wire and then follow the plug wires in the direction of rotation of the rotor (clockwise) using a fireing order of 1342. That should get it to fire up enough to assess the situation. If it does not run well, try lifting trhe distributor and moving the gear mesh one tooth in either direction and assess the improvement or lack there of. Take your time and don't get frustrated. You are almost there and the results will be worth it.

It would help if you stated the year of your engine and the type of injection/carberation and the manafacturer of your ignition system.

Robert Hill in Memphis, TN
 

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Unless later models are different and have a helical gear (latest alfa I've owned was a 78) , then the dog gear on the distributor is offset slotted and only goes in one way--no moving one tooth. If so, then follow above setup instructions from 105 guy. Don't know about later model engines but earlier distributors have a hold down clamp and the distributor shaft will spin wherever you want it when the clamp is loose so you can adjust the timing by loosening the clamp and rotating the distributor. Of course all of this depends on the rotor being at #1 when you're on the compression stoke of #1
 

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The later Bosh equipped models have the distributor clamp fixed and then secured with a headless bolt, so there is No loosening the clamp and twisting the body of the distributor in the clamp, unless you cut the headless bolt off and replace it with a nut and bolt you can loosen and then do the twist. And come to think about it, fivesay is correct unless you access the oil pump and turn it's drive shaft one tooth in either direction, not easliy accomplished with the oil pan already in place. In a case like that then if the distributor drive (oil pump drive shaft) is incorrectly positioned, then cutting the headless bolt and replacing it with one you can manipulate would be the most practical solution (if the oil pump drive shaft is improperly aligned during reassembly of a rebuilt engine). On the Bosch equipped engines they set the timing right on the mark at the factory and then "seal" the distributor as described above and "seal" the idle adjustment screw by placing a plug in the hole the screw is in, to keep owners and shade tree mechanics from disturbing the factory settings. Of course you can overcome anything with a hack saw and a hammer, even factory "sealed" settings to the timing and idle.

Robert
 

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You can't set the timing on a L-jet by turning the dizzy. (likely Motronic either, but I don't have proof in front of me, so won't persue that)

Yes, you can cut the shear bolt and move the body, but it has no effect on actual timing other than to screw it up for the ICU.

The tick mark on the edge of the dizzy body has to be aligned with the tick mark on the rotor to allow the ICU to allow timing advance and retard over the full range based on its mapping and what info it gets from the flywheel sensors and manifold vacuum sensor.

Moving the tick mark away from the rotor by turning the body not only doesn't have an actual effect, it also restricts the amount the ICU can advance or retard the timing as the dizzy on L-jet is literally nothing more than a switchbox that fires X plug when the ICU activates the coil.

Useable advance and retard range is literally a function of how broad the blade on the rotor is and it's alignment in the dizzy body.
ICU tells the coil to fire, and if the rotor isn't useably aligned with a cap terminal, fire doesn't take place.
Move the blade, or use a points type rotor in there (EFI rotor has a much broader tip) and you've literally cut the available range by the amount the body was moved or the rotor is narrower. (x2 even, because of the half rotation speed of the dizzy rotation)
 

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All of this which goes to prove - when rebuilding an Alfa engine you MUST get the oil pump drive shaft is it's proper alignment (the offset slot in the top which the distributor keys into) in relation to TDC on the # 1 compression stroke. If you don't, then it is repostion the oil pump drive shaft in it's proper position by removing and replacing the pump (oil pan off) no matter how inconvenient it may be. If you have Bosch FI and ignition, there will be no salvaging the situation by monkeying around with the distributor position. Apparently on a Bosch system, the only fuction of the distributor is to point the firing impuse toward the correct spark plug - Period.

All and all, a very interesting and informative discussion. Thank You to Darren for putting all this in proper context.

Now if gav will just satisfy all our curiousity and tell us how it all worked out!

Robert
 

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... the dog gear on the distributor is offset slotted and only goes in one way....
If the dizzy or other parts are a bit worn, it IS possible to put it in 180 degrees out. It barely fits if this happens, but it feels like a perfect tight fit. Only, a few thousand revs later the oil pump drive shaft that powers the dizzy will snap off.

I learned this the way of all really good learning - I was stranded in a not-so-nice part of San Jose at 11:00 pm, and AAA was really not interested in coming, at least not without a LOT of yelling and begging.

Robert
 

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Noticed that there aren't any "Sticky" Threads in the Engine rebuilding forum.
As well, this topic could fall under electrical...

Assuming a stock engine, it is my understanding that there are numerous similarites across Alfa powerplants. Could this ignition topic start on a more basic level and build detailed information in a more structured setting on the BB..?

Perhaps added to exisiting sticky threads?
 

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My engine has just been rebuilt and im trying to start it for the first time. The timing seems way off and will not start just an occasional POP :eek:!! Im very weak in this area. I located tdc on number one but my distributor is facing number 3?? Can someone give me a detailed description on how to correct this.
THANK YOU
GREGG
If the rotor is pointing at #3 when #1 cylinder is placed at TDC then your oil pump was installed with the distributor drive dog 90 degrees off of where it should have been. The only practical solution now, assuming you don't want to take the engine half apart, is to rotate the plug wires on the distributor cap clockwise one position.

If this is a breaker point ignition then, with #1 at TDC use an ohmeter between the primary wire from coil to distributor and ground and adjust the distributor to a position where the points first open and continuity is broken. That will be close enough to get started then use a timing light to do the final adjustment. On a SPICA injected engine that is supposed to be 5 degrees after TDC but with premium fuel you should be able to run it right about TDC or possibly a few degrees advanced.
 

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If the rotor is pointing at #3 when #1 cylinder is placed at TDC then your oil pump was installed with the distributor drive dog 90 degrees off of where it should have been. The only practical solution now, assuming you don't want to take the engine half apart, is to rotate the plug wires on the distributor cap clockwise one position.

If this is a breaker point ignition then, with #1 at TDC use an ohmeter between the primary wire from coil to distributor and ground and adjust the distributor to a position where the points first open and continuity is broken. That will be close enough to get started then use a timing light to do the final adjustment. On a SPICA injected engine that is supposed to be 5 degrees after TDC but with premium fuel you should be able to run it right about TDC or possibly a few degrees advanced.
I didn't read the original post carefully enough. Without thinking, I assumed it was 180 degrees off. You say it's pointing at #3, so, in fact, it is only 90 degrees off and this is the correct advice. Thanks kcabpilot from an N2S-5 pilot.
 

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Discussion Starter #16
Hey guys sorry i took so long to get back girlfriend made me go do the 4th with her family AUGG?!? So this is the deal. I had a friend come help me and we figured that the oil pump was installed 90 off. I took the pan off and no way was that getting moved without removing the sump. Sooo we rotated the bottom clamp on the distributer (I dont now what its really called im at work dont have my book) and and made a "new number one and then replaced wires in correct fire order and down the road she went.
Thank you for everyones input
 

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Discussion Starter #17
I have an 81 spider with webers and a Marellieplex ignition
 

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Discussion Starter #18
Just updating my profile wanted to see how it looks
 

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Discussion Starter #20
This site is truly awesome! Very well organized and stuffed with great info. Every time i log in i always find an interesting read.The folks that have replied to my questions have been terrific. I found the site a few years ago but never used it. I just became a subscriber and yes its totaly worth it. The car has been in storage from 04-09. I purchased a house and didnt have the money or time for it. The last two years I tore into it with new motor top paint tires rims new interior. I just drove it today for the first time about 50 miles. Im taking it to my mechenic friend and hes going to set up the webers and then back to paint shop for glazing. Ill try to get some pics up it is really coming together. I really miss driving it.
 
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