TDC -- Top Dead Center -- Timing Pin ???
- Thread starter H. L. Chauvin
- Start date
Purdy Swoft
Well-known member
Yo Bill, All of mine sez Chick ah lunk ah- chick ah lunka- chick ah lunka with the spark fully retarded. I guess mine has a southern accent. I spose the ones on the left coast have their own accent. Never thought about that afore. Wonder iffen you moved back to Oklahoma it would develope a hokie pokie okie sound?
Chuck Sea/Tac
Well-known member
George, were these made by Borg Warner, or some other company?
Mike V. Florida
Well-known member
Great tutorial for "I've tried everything but it still won't run right".
BILL WILLIAMSON
Well-known member
Purdy, you're FUNNY! You just made my day!!
Why's your first Chick ah lunka ah CAPITALIZED? Does it have higher compression? And where's your #4 chick ah lunka ah? Maybe that distributor body's jumpin' spark out the top, to the #3 GOLD spark plug strap??In OKLAHOMA, Chief used to say, that they said, "CADILLAC AH-CADILLAC AH-CADILLAC AH-CADILLAC AH" We NEVER saw a CADILLAC, WE JIST HURD about them!
NO! I'm NOT gonna' do a research trip to OKLAHOMA, to hear how they sound like there!
Bill W.H. L. Chauvin
Well-known member
In response to Mr. rollingsculpture in his reply #6 & to Mr. Ron W. in reply #21, about finding TDC, there were many vehicle manuals written in the past about how to find "exact" TDC for timing engines.
Some manuals indicate using the dial caliper I mentioned & used, & some indicate using a piston stop plate fixture whereby both function similarly.
If one is interested, one can read details about TDC & see illustrations on how to find "exact" Model A TDC with a degree wheel & a piston stop plate on page 1-39 of Volume II of "Model A Ford Mechanics Handbook" by Mr. Les Andrews.
What happens is when an engine crankshaft is slowly rotated CW the piston first reaches a high point BTDC & moves no higher; however, the crank still turns a few "CW degrees" before the piston begins to descend; "and" when the crank is slowly rotated CCW the piston again first reaches a high point ATDC & moves no higher; however, the crank still turns a few "CCW degrees" before the piston begins to descend.
As one can witness, the few "CW degrees" measured on a degree wheel are usually equal to the "CCW degrees" measured on a degree wheel & that the exact TDC occurs at a mid-point between the BTDC degree reading & the ATDC degree reading.
Hope this helps.
Some manuals indicate using the dial caliper I mentioned & used, & some indicate using a piston stop plate fixture whereby both function similarly.
If one is interested, one can read details about TDC & see illustrations on how to find "exact" Model A TDC with a degree wheel & a piston stop plate on page 1-39 of Volume II of "Model A Ford Mechanics Handbook" by Mr. Les Andrews.
What happens is when an engine crankshaft is slowly rotated CW the piston first reaches a high point BTDC & moves no higher; however, the crank still turns a few "CW degrees" before the piston begins to descend; "and" when the crank is slowly rotated CCW the piston again first reaches a high point ATDC & moves no higher; however, the crank still turns a few "CCW degrees" before the piston begins to descend.
As one can witness, the few "CW degrees" measured on a degree wheel are usually equal to the "CCW degrees" measured on a degree wheel & that the exact TDC occurs at a mid-point between the BTDC degree reading & the ATDC degree reading.
Hope this helps.
Last edited:
George Miller
Well-known member
Not sure who made them, but I found they were off when building engines back then. I always check the gears against a nos gear. The ones I have used in the last few years seem to be good. If you have a old one, I would check it before use.
Purdy Swoft
Well-known member
Purdy, you're FUNNY! You just made my day!!
In OKLAHOMA, Chief used to say, that they said, "CADILLAC AH-CADILLAC AH-CADILLAC AH-CADILLAC AH" We NEVER saw a CADILLAC, WE JIST HURD about them!
NO! I'm NOT gonna' do a research trip to OKLAHOMA, to hear how they sound like there!
Yo Bill, Most of my A models have higher compression. Don't know why I capitalized the first C or left off the last chick ah lunk ah. Somtimes I mess up with my typin and spellin. I did once have the number three jumping through the cap body to the number four on the coupe. It didn't effect anything untill higher rpm. When I finally found the problem, I blamed it on the cap. I think that the real problem was that the plug wire strap was too short and actually layed right on the cap and burned through to the number four lead inside the cap. I'm just gussing that being as they cadillac in Texas, Oklahoma is right above Texas so thats why they also cadillac there. I know an old mechanic that would say push the spark up and listen to it A model.
BILL WILLIAMSON
Well-known member
Were they really off, George? All the crank gears I've seen, the mark is even with the R/H edge of the crankshaft key. It's just a center punch mark, behind the slinger. The dimple on the cam gear is ON a tooth, the corresponding dot on the crank gear is in the BOTTOM of a tooth knotch, thus it has to be 1/2 tooth off, or the width of the key. It's like the MALE/FEMALE thing!
Gregg always had trouble comprehending the MALE/FEMALE pipe fitting thing, until Chief made a simple gesture with his fingers!!
"AAH! I got it"!!Bill W.
George Miller
Well-known member
Were they really off, George? All the crank gears I've seen, the mark is even with the R/H edge of the crankshaft key. It's just a center punch mark, behind the slinger. The dimple on the cam gear is ON a tooth, the corresponding dot on the crank gear is in the BOTTOM of a tooth knotch, thus it has to be 1/2 tooth off, or the width of the key. It's like the MALE/FEMALE thing!
Gregg always had trouble comprehending the MALE/FEMALE pipe fitting thing, until Chief made a simple gesture with his fingers!!
Bill W.
Yes the key way was located 1/2 a tooth off. I think most people never check things like that. But it changes your valve timing and top dead center of the crank, if you use the pin.