TDC- How do i find it?

[Blue68Camaro]

So i am finally ready to install my Distributer so how do i go about finding TDC.
I dont have any special tools and there is no timing marks so other than that what are some ways to do this?

[cepx111]

Assuming this engine is in the car I would take the #1 spark plug out and have someone bump engine over very slowly ( this can be tricky) a remote bump starter button works allot better.
Stick your finger in the spark plug hole when you start to feel compression your on the #1 cylinder's compression stroke, when the piston is all the way up ( some people use a long skinny screwdriver to determine this) the piston will be at TDC for #1 cylinder. Then you can drop your dist in making sure the rotor button lines up with the # 1 plug wire on the cap when the dist is all the way down.
If the engine is out of the car on a stand, I'd just do same procedure except using a crankshaft turning tool or a socket on the damper bolt.
When you do determine TDC make a mark on your balancer if there isnt one already and line up the pointer on the timing cover. It will come in handy later when you put a timing light on the engine.
Hope this helps, Charles

[Tod74]

If all you want to do is put in the distributor do what was posted above...but if you want to find true top dead center then The only right way to do it is with a degree wheel and piston stop. Degree wheels don't cost that much...but probably difficult to use in the car. You could possibly try some of that timing tape on the balancer to sort of use it like a degree wheel. Put the piston stop in the plug hole ,rotate the engine BY HAND!! until it hits the stop, make a note as to where your timing pointer is at on your degree wheel or balancer marked with the timing tape, rotate it back the other direction until it hits the stop, note the location on the degree wheel again...remove the stop and exactly half way betwween those two points will be true top dead center.

I hope I didn't screw that up too bad. :? Someone Correct me if I explained that wrong.

[signsbyesa]

and just incase like my first time, i thought i had tdc and installed the
distributor and the car backfired a storm turns out i had to pull
the distributor and install it 180 degrees and it worked great, and
i realy thought it was at tdc with the first piston up but it was wrong
so that might help, i can do it with my eyes closed now :D

[Tod74]

and just incase like my first time, i thought i had tdc and installed the
distributor and the car backfired a storm turns out i had to pull
the distributor and install it 180 degrees and it worked great, and
i realy thought it was at tdc with the first piston up but it was wrong
so that might help, i can do it with my eyes closed now :D

It was at TDC......of the exhaust stroke. That's why cepx111 told him to put his finger over the hole,so he would feel the compression.

[Blue68Camaro]

Thanks guys!

[signsbyesa]

finger over hole, by this time you can hear the air coming out, and'
your timing marks are lined up 8)

[thetanman101]

If your TDC mark doesn't alingn with the 0 degree mark on the balancer, do you align for 36 degrees counting from your TDC mark and just ignore the original numbers on the balancer?

-Tanner

[Tod74]

If your TDC mark doesn't alingn with the 0 degree mark on the balancer, do you align for 36 degrees counting from your TDC mark and just ignore the original numbers on the balancer?

-Tanner

You can buy an adjustable pointer.

[Blue68Camaro]

OK check this out, i turned the motor over and walla i looked at the balencer and i do see timing marks. Can i use them? Where should the mark be to be at TDC to set the distributer in. At 0 or at 36??.
I have those blasted agnle plugs and cant seem to really tell when the piston is at the top. Can i use those marks to re-install the distributer?

[Tod74]

If your distributer is locked out then yeah,set it to 36 or 38 or whatever...but if it's not locked out, As long as it is close to TDC on the compression stroke you'll be able to get it started..just get it running then set the timing to 34-38 or whatever you want with all advance in.If your distributer isn't locked out and you install it 36 deg BTDC , when you start it and the centrifical advance and or vacume advance comes in you will have way too much timing.
If for some reason you can't get a finger on the spark plug hole to tell when it's on the compression stro ke,just watch the rocker arms.

[thetanman101]

If your TDC mark doesn't alingn with the 0 degree mark on the balancer, do you align for 36 degrees counting from your TDC mark and just ignore the original numbers on the balancer?

-Tanner

You can buy an adjustable pointer.

That's not what I'm asking. Let's say TDC on mine is at the 10 degree mark on my balancer. I want my motor running at 35 degrees total. Would I add 35 degrees to my 10 degree TDC mark and set it at the 45 degree mark on balancer?

-Tanner

[Blue68Camaro]

Can i have my thread back? :) I dont even know who is responding to who and i dont know what locked out means. I would like to know what the pointer should point at when i am at TDC? At 0 or at 36? or ?

[Tod74]

Can i have my thread back? :) I dont even know who is responding to who and i dont know what locked out means. I would like to know what the pointer should point at when i am at TDC? At 0 or at 36? or ?

locked out means you are running full advance all the time.

http://www.classiccarauto.com/impala/how_to/install_distributor.shtml
http://www.type2.com/library/electrip/timex.htm

[Blue68Camaro]

OK so lets say i have my engine at TDC and i drop the distributer in all the way, cant i just put on the cap and install the wires starting from where the rotor tab is at as number one and install the wires with the firing order?

[Tod74]

OK so lets say i have my engine at TDC and i drop the distributer in all the way, cant i just put on the cap and install the wires starting from where the rotor tab is at as number one and install the wires with the firing order?


Yes

[Blue68Camaro]

Thank you, i will give it a shot.

Tom

[Blue68Camaro]

Couple more questions. I have the motor at TDC (I think). The little needle is at 0 on the balencer and i think its on the compression stroke ( I felt a woosh of air at the number 1 spark plug). But now i dont know where to start the firing order. The distributer can be turned and i can easily have number one be at two different spots. How do i know which one is the true number one? Also which way does the engine turn on the rotor?

I am sorry to not know all this stuff, i knew it once but at 37 and 20 years out of the muscle car hobby i have long forgotten this stuff.

I am just trying to avoid putting this car back together and having to redo stuff. If i can do it right the first time it might limit what goes wrong (something always does) at the end.

[davis419b]

Either one will work as long as you put #1 plug wire in the cap directly above where the rotor is pointing. Just make sure you are able to move the distributor both ways so you will be able to set the timing Continue placing the plug wires on going clockwise as per the firing order usualy 18436572 unless you have a 7/4 swap cam which will swap those 2 numbers in the firing order.

[Tod74]

The company my dad works for (GAPCO INC) makes a thing called "Whistle Dic" that goes in the spark plug hole and whistles as the piston comes on compression stroke. Great for when you work alone.

http://www.gapcoproducts.com/

[topsportsman1]

Hey Tod
By any chance you wouldn't have 8 of them in your back pocket would ya? I'd like to have 8 of them for when I'm bored this winter,maybe I could get my engine to whistle a top 40 tune and get rich over the winter,just some thing to think about :P

[cepx111]

Yes you can do it that way but,
I like to get the the rotor pointing about 4 o'clock for number 1, using the firewall as 12 o'clock, with the rotor shaft turning clock wise.
That would be about where the factory would put it.
Always seems to make it easier routing the wires with that configuration.
goodluck, Charles

[cepx111]

Having a distributor "LOCKED OUT" simply means you have all your advance in it (say like 38 degrees) at an idle. There is no vacuum advance or centrifugal advance at all, they are "LOCKED OUT" or disabled mechanically.
< The reason behind it is that in a full race motor like in dragracing you dont want to wait for a advance curve to come into to play, you want instant throttle response and imediate engine excelleration since 99 percent of the time your at WOT anyway. There is no need for a distributor with a advance curve like in a street machine where your on and off the throttle contionously or at part throttle cruising around,
so you lock out all the advance mechanisims, and just set your distributor at full advance. Usually used in conjunction with some sort of start retard or by seperating the cranking and ignition circuit to help ease starting difficulties in a fully advance engine.
Cp