: distributor question



quins90lac
10-06-11, 03:41 AM
where is the top dead center on a 4.5 distributor. i got to wires figured out but i think i jumped a few teeth in one detection or another so im going to put it at TDC and go from there. i have a FSM but all it say is position the rotor between the #1 &#8. if this don't work it going to the mechanic to figure out whats wrong.

ehall
10-06-11, 10:41 AM
TDC refers to the #1 cylinder being at the top of the compression stroke

Not sure I understand exactly what you're asking

quins90lac
10-06-11, 03:25 PM
like you looking down at the top of the distributor with out the cap on where dose the rotor need to point for TDC on the distributor.

ehall
10-06-11, 10:49 PM
On mine, the square block for the coil wires on the side of the distributor cap points between the throttle body and the EGR

http://www.eric-a-hall.com/gallery/albums/cadillac-4-9-swap/4_9_TBI_Installed.sized.jpg

quins90lac
10-07-11, 12:22 AM
im talking about in the procedure to reset TDC if its lost . in the FSM its page 6d4-5 section D of the procedure.

daniel58
10-07-11, 04:11 AM
With the harmonic balancer at the TDC mark the rotor should point to #1 in the distributor cap. It will turn a bit when you install the distributor so you have to allow for that so its pointing to #1 when seated.

dennis93coupe
10-07-11, 01:26 PM
Here's what I would do...
1. Remove #1 spark plug
2. Place your finger over #1 spark plug hole and turn crankshaft in the correct rotation slowly until compression is felt. (this will indicate if you are on the compression stroke for #1)
3. Align timing mark on pulley to ")" on engine timing indicator.
4. Turn rotor to point between #1 and #8 location on you distributor cap.
5. If you can't get the rotor to align between #1 and #8 and drop in, pull the distributor out and turn the oil pump shaft about 10-15 degrees. Distributor should drop in and rotor should point close to #1.

FREDFLYPOGGER
09-21-14, 06:27 PM
hi
tried starting the car today but no luck. I decided to follow the service manual and removedthe distributor, routed the spark plug wires according to service manual.Inserted finger in cylinder one, slowly turned over motor. Felt compression stroke.It says then to align timing mark on pulley to 0.I am not sure if they mean remove pulley then align or try aligning while cranking motor.That can't been done since when I find top dead center the 0 timing mark is way off. I tried installing the distributor anyway when I felt compression stroke. I installed distributor like Service manual states and put rotor between 1&8 cylinder on the cap. I tried starting but it just back fired.I tried rotating distributor but no luck.Any help would be appreciated.
thanks

carnut
09-21-14, 09:07 PM
Why duplicate threads??

limo1
01-03-15, 08:41 PM
You want that rotor arm pointing at the #1 spark plug post when the coil fires so at around 20-30BTDC if the rotor is not set correctly coil will fire when positioned between #1 and 8 and could jump to wrong plug.. Once the motor starts need to turn that dist to get the 10 degrees on timing light and hope backfiring goes away. ECM bypassed.
After set pull cap look at flywheel mark at 10BTDC where is the rotor pointed is it coming into the #1 contact or going away from it when turning the motor slowly.it should be on back side of contact.
advance can add another 30 degrees extra so still need the rotor looking at the 1 plug terminal not 8.
So set the rotor when installing a few degrees before #1 plug on the dist cap maybe one dist tooth backward.
Double check your firing order?? any dist cap tracking marks inside clean cap and rotor.

carnut
01-03-15, 10:21 PM
limo1 you're wasting your time on 2 month old threads! Whatever help he needed he must have gotten somewhere else.

themachinist
01-04-15, 01:12 AM
these threads can generate traffic from search engines such as google. the reason i started my account is because of threads i found by searching. by answering old threads you could be helping someone that is simply searching the forum or the internet. the forum is a repository of information and it doesnt harm anyone to add to it.

cadillac_al
01-05-15, 06:01 PM
If anybody is removing their distributor in the future, line up the rotor with something so you can put it back in the easy way, the same way it came out. I always point them at the firewall but these 4.x's are at an odd angle so I may be inclined to point it at something else.