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Discussion Starter #1
hello guys im new at this so bare with me.i have a 74 gtv wich im trying to install a bosch distrib. i also have the bosch blue coil can anybody help me with step by step thanks very much. Ben ALFA FOREVER
 

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I don't know the details of your model or the Bosch distributor to give you exact step-by-step instructions. but here goes anyway.

If the distributor has points, set the point gap, position the engine so the #1 piston is at TDC on compression (keeping in mind the piston goes to TDC twice during a complete 4 cycle sequence). Note the position of the slot down inside where the drive end of the distributor fits. The end of the distributor shaft has a matching piece that fits into that slot. The slot is slightly off-center so the drive should only fit one way. Insert the distributor so the key fits into the slot. You may need to wiggle the rotor shaft around a bit until it fits properly. The base of the distributor should now be all the way into the engine block. If it is not the key is not fully seated into the slot.

Now you can statically time the distributor. Usually there is a specification for X number of degrees before TDC. Carefully turn the engine so the crank is at that position. Now turn the distributor body until the points are just beginning to open (which is where it would trigger the coil to discharge and produce the spark). You can use a 12V test light or an ohm meter to see exactly when the points begin to open. Once you have the distributor in the right position, tighten the clamping bolt.

Now make note where the rotor is aimed. That section inside the distributor cap is for the #1 spark plug wire. The remaining wires are attached in the correct firing order. 4 cylinder engines are usually 1-3-4-2. The Alfa rotor turns clockwise (when viewed from above) so install the rest of the wire following that firing order.

More exact timing is done with a strobe light. Again there are specifications for where the spark should occur, usually expressed as X degrees BTDC @ a certain rpm.

If you have a distributor with electronic ignition then the basics are the same but I do know off hand how to statically time it.
 

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Here is my process:

1) Remove the cam cover.
2) Rotate the motor to TDC. The cam lobes on #1 will point to the outside and the timing marks will line up with the marks on the back of the cam caps.
3) Verify that the timing mark on the crank is showing TDC as well. Replace the cam cover.
4) Notice that the key on the bottom of the dizzy is offset. That will allow the dizzy to only lock into one location.
5) Loosen the dizzy locking bracket so that you it can rotate.
6) Remove the distributor cap and rotate the rotor so that the key on the bottom lines up approximately with the slot in the bottom of the distributor hole.
7) Make sure you have the proper O-ring installed in the the groove of the front cover base NOT on the dizzy shaft. Lube the shaft with some grease or at least some engine oil.
8) Install the dizzy in its hole. When it bottoms out rotate the rotor until the key drops into the slot. Push the dizzy down in the rest of the way until it is seated to the front cover. Make sure it is nice and locked in place.
9) Note the position of the rotor. It is going to point to the #1 plug wire.
10) Remove all the plug wires and install the cap remembering which is going to be #1. Rotate the dizzy in either direction to get the position. Don't get too worked up about it though - just approximately.
11) Decide which plug wire is #1 and install it. Now finish with the rest. Firing order is 1-3-4-2.
13) Connect the coil wire from the center pole to the center position of the coil.
14a) If this is an electronic distributor there should be two wires coming out. Black to the negative side of the coil, red to positive. There should also be an ignition wire (green or green/black coming from the wiring harness of the car) - this goes to the positive side.
14b) If this is a points and condenser style, then there will be only a black wire - that goes to the negative. There should also be an ignition wire (green or green/black coming from the wiring harness of the car) - this goes to the positive side.
15) If Everything is set up properly then you should be able to start the car. Rotate the distributor in either direction to get it to start and hold an idle. CCW is advancing the spark.
16) Now it is time to get out the timing light. Notice that there are a number of marks on the crank pulley. An inch or so from TDC is a mark called "M". This is the maximum advance position. Make sure you can see it (Perhaps highlight it with whiteout).
17) Start the motor and with an assistant on the throttle and distributor and you on the timing light rev the motor. You will see the "M" mark begin to approach the timing mark. It should reach the mark at no more than 5,000 rpm. Rotate the distributor to make it happen.
18) When you are there, allow the motor to drop back to idle. If you are not idling properly you will need to adjust the fuel system. The important position of the dizzy is the high speed advance NOT the idle position.
19) Tighten the dizzy clamp and verify that it is tight.

That's it!

Good luck...
 

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Discussion Starter #4
guys thank you very much you have been very helpful .i will do that tonite hopefully i can get it to start .will keep you posted. ciao.Ben. i also was talking with papajam and he mentioned the o ring at bottom of distrib.again guys THANK YOU for all your help.
 

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To this excellent advice, I will add one admonition. The distributor only fits properly one way. You will know it's in properly when it feels really solid. Once you know the difference in feel you'll instantly know when it's right. The problem is that to a newbie the "wrong" way feels right because it will sorta fit you don't know the difference. It is, therefore, very easy to put the distributor in 180 degrees out of time which will leave you confused because you'll think you did it right. (Ask me how I know this. :) )

If you'll look at the distributor you'll notice that the drive key is slightly offset as is the slot in the oil pump driver shaft. These have to be in alignment. If you get it wrong don't worry: I've seen professionals make the same mistake.
 

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Good point Jim. Also, I amended step (7). I originally said to install the O-ring on the shaft of the distributor. WRONG (thanks papajam for setting me straight)! It should be installed in the groove of the front cover base. Lube up the dizzy shaft first and check that there aren't any burrs at the bottom to hang up on the seal. It should provide some resistance when installing at first but once you get past the seal it will glide down to the key slot. Then as Jim suggests, rotate the rotor until it drops in nice and solid.
 

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I wish I had a dollar for everyone who has inadvertanly tried to start an Alfa they had 180 out, I'd definitly have to give myself a couple.
If you get lazy and don't want to pull off the cam cover you can pull #'s 1 and 4 plugs, when at TDC you will see one of them with the vlaves slightly open, that means it's firing on the other cylinder and the rotor should be pointing to that cylinder.
 
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