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78 620, L20B foreign matter in combustion chamber.


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#321 racerx

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Posted Yesterday, 05:47 PM

U don't need the book, put the dist back w wires and lift it up, then see where the rotor is pointing.

#322 wayno

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Posted Yesterday, 06:03 PM

It doesn't matter where the rotor is pointed as long as it is pointing directly at a plug wire post on the cap and you have some adjustment room to time it, that post will be number one spark plug wire, and the firing order is 1, 3, 4, 2 counter clockwise.

Normally #1 is at 3:30ish standing on the drivers side looking at the distributor rotor, yours appears to be close to that, it has to point directly at a post on the cap and still have enough adjustment to time the engine properly.

 

The engine has to be at TDC, if it is not at TDC you are just guessing and that will catch up with you sooner or later. likely sooner.


 

 


#323 racerx

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Posted Yesterday, 08:02 PM

If things are not lined up, won't his timing mark on the pulley be off?

#324 datzenmike

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Posted Yesterday, 08:37 PM

Was this engine running? If all you've done is set to TDC and removed the head it will still run when done.


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#325 Atikin9000

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Posted Yesterday, 11:17 PM

Was this engine running? If all you've done is set to TDC and removed the head it will still run when done.


It was running and just like you said I just pulled the head off.

Also the pulley mark is at 0

#326 distributorguy

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Posted Today, 05:29 AM

Common mistake.  The ignition doesn't fire at 0.  It fires at between 10-40 BTDC,  



#327 datzenmike

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Posted Today, 06:16 AM

The point is that it was running like this, so nothing has been changed and it will start and run as before.


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#328 distributorguy

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Posted Today, 06:47 AM

...which may not be correct.  Its worth checking.  



#329 racerx

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Posted Today, 07:46 AM

A car could be running before but things may not have been aligned and was just enough to run. Since the head is off, good to check if everything is buttoned up.

#330 datzenmike

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Posted Today, 07:54 AM

There's no correct way just the way most set theirs up. 180 out isn't 'correct' but works perfectly. There are 40 possible positions with 4 working perfectly at 90 degree increments and possible a tooth on either side that still allows timing adjustment. This can be done to turn the module away from exhaust heat or spin the vacuum advance around or to move the distributor to get adjustment on one of 6 ? different timing plates.  I have a modified Z24 timing plate on my '79 matchbox.  


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#331 wayno

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Posted Today, 09:48 AM

Are we not talking about setup here now, how to set it up so it starts without valves hitting pistons and such.

If the block is at TDC(there is no 180 out on the crank when setting it up), and the cam gear notch is where it is on the plate then this part is good.

His rotor is close in the photo he took of it, if it points directly at a spark plug wire post, that is number 1 spark plug wire as long as he has timing adjustment room like I have in the photo below.

DSCN7426.jpg

If the bolt is not in the middle and the rotor is not pointing directly at a post on the distributor then some adjustments will need to be made to the dist/oil pump drive shaft.


 

 


#332 racerx

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Posted Today, 09:51 AM

True, maybe I'm just ocd.