318 Timing Chain Question.

-
dkamp

dkamp

Active Member
Joined
Jan 14, 2023
Messages
43
Reaction score
12
Location
Terre Haute, IN.
Help Please..........
I had my engine at TDC for Cyl #1 and just removed the Timing Chain and gears. Both the Markings were at 12 o'clock.
I did a Boo Boo, Huh? it should have been TDC on #6 I think?????
What should I do to fix this situation? (FYI, Engin is In the truck and it Very hard to get to the front from the Top, Bottom cannot be done because this is a customized 1946 with a 1986 318 Engine).
Option 1: Put chain back on and find a way to roll it one rev?
Option 2: When I put it together put both at 12 like the Old came off?
Option 3: ?
 
I think they should be "dot to dot" crank at 12 cam at 6. You could put it back the way it was and spin it and see if it lines up dot to dot. Crank will turn 2 times for every 1 turn of the cam.
 
I assume only way to crank it over would be by using the Crank Bolt?
If I hook up Battery and use the starter it pretty Unpredictable on how much it would turn over. I do have the Plugs out.
Crank bolt would be best.
About how many revs would that be?
 
I would go with your option 1, put the chain back on and turn the crank 1 rev by hand with the crank bolt, then check the cam and crank dots are lined up crank at 12, cam at 6 o clock .
 
If both dots were at 12 O'clock, you did it right. That's TDC for #1.
 
Last edited:
Dartswinger70 said:
I think they should be "dot to dot" crank at 12 cam at 6. You could put it back the way it was and spin it and see if it lines up dot to dot. Crank will turn 2 times for every 1 turn of the cam.
Click to expand...
Dot to dot is timed up on #6, not #1.
 
dkamp said:
Help Please..........
I had my engine at TDC for Cyl #1 and just removed the Timing Chain and gears. Both the Markings were at 12 o'clock.
I did a Boo Boo, Huh? it should have been TDC on #6 I think?????
What should I do to fix this situation? (FYI, Engin is In the truck and it Very hard to get to the front from the Top, Bottom cannot be done because this is a customized 1946 with a 1986 318 Engine).
Option 1: Put chain back on and find a way to roll it one rev?
Option 2: When I put it together put both at 12 like the Old came off?
Option 3: ?
Click to expand...
I have done a couple timing chains pretty recently. My understanding is dots lined up both in 12:00 position is correct for TDC on #1. Dots lined up dot to dot at 12 and 6 will have cylinder #6 at TDC.
 
I'm leaning toward leaving on TDC #1. then be careful to get it right with Dots on 12 and 12.
Use a straight edge to verify. It would have to be a tooth off to get it wrong.
I will have an issue that I'm doing it from high above looking down, and cannot get a front view. I guess I could use my iPhone and take a Picture to confirm/compare.
Opinions?
 
dkamp said:
I'm leaning toward leaving on TDC #1. then be careful to get it right with Dots on 12 and 12.
Use a straight edge to verify. It would have to be a tooth off to get it wrong.
I will have an issue that I'm doing it from high above looking down, and cannot get a front view. I guess I could use my iPhone and take a Picture to confirm/compare.
Opinions?
Click to expand...
Well, what most people do is time it dot to dot for the ease if installation, then turn the crank ONE revolution and you're on #1 TDC. But, if you didn't pull the distributor, you can time it dot to dot and you'll be fine. It's all relative to exactly WHAT you're doing and you've not disclosed that yet.
 
If at TDC #1, One rev would be at #6 TDC and the Dots together at 12, and 6, Right?.
From that position there is really no need to go back to #1 at TDC. I have not removed my Distributor.
 
dkamp said:
If at TDC #1, One rev would be at #6 TDC and the Dots together at 12, and 6, Right?.
From that position there is really no need to go back to #1 at TDC. I have not removed my Distributor.
Click to expand...
Correct. I believe you have a grasp on it.
 
For every one revolution of the crank the cam goes 1/2 turn. Turn the crank one revolution and the marks will be correct. If both valves are closed intake just closing that would be firing stroke . Install the distributor with rotor pointing to No.#1. No need the take the chain off. As long as the dots were 6 or 12 respectively you did nothing wrong except possibly distributor rotor location changing 180 degrees
 
Oh, fer Chrissake, people-
Just put the new gears and chain on in the exact orientation that you pulled the old ones off. If the dots were both at 12:00, and you haven't moved anything; then put the new one in with both dots at 12:00. Button it up, time it in case the ignition was a bit off due to old chain slop, and you're done.
 
Oldmanmopar said:
For every one revolution of the crank the cam goes 1/2 turn. Turn the crank one revolution and the marks will be correct. If both valves are closed intake just closing that would be firing stroke . Install the distributor with rotor pointing to No.#1. No need the take the chain off. As long as the dots were 6 or 12 respectively you did nothing wrong except possibly distributor rotor location changing 180 degrees
Click to expand...
THIS THIS THIS THIS THIS THIS

So far as I know Mopars and Chevs are timed no6 when "dot to dot" and no1 when 12 and 12
 
Geez some of you need to take a Zanax....the feller said he cant see it from below because its a 46 custom something so, id figure do to dot would be easier to see even with a mirror. The distributor isn't out of the car so non issue there. he could either line it back up 12 and 12 the way it came apart OR dot to dot the distributor would turn with the cam on lineup p and the thing would start wouldn't even need to check timing etc. Only thing OP has to worry about is being a tooth off either way from not being able to see it straight on if that's the case... hey sorry I replied first wont happen again. To anyone else I say buy a book...it would be quicker to go to the bench look at it instead of asking on a forum :)
 
Last edited:
If you hold the chain and sprockets in your hand by the upper sprocket. Align the marks 6 on the top sprocket and 12 on the bottom sprocket . Let it hang. You can turn them any way you want to get them to go on. As long as you don't jump a tooth top or bottom it will be in time . You may have to turn the crank to get the keyways in the right spots to go on but the timing chain will be in time.
 
Last edited:
Dartswinger70 said:
Geez some of you need to take a Zanax....the feller said he cant see it from below because its a 46 custom something so, id figure do to dot would be easier to see even with a mirror. The distributor isn't out of the car so non issue there. he could either line it back up 12 and 12 the way it came apart OR dot to dot the distributor would turn with the cam on lineup p and the thing would start wouldn't even need to check timing etc. Only thing OP has to worry about is being a tooth off either way from not being able to see it straight on if that's the case... hey sorry I replied first wont happen again. To anyone else I say buy a book...it would be quicker to go to the bench look at it instead of asking on a forum :)
Click to expand...
WTF? How did we know what he was doing from his original post? If he was building an engine, he would need to stab the distributor, right. Right? RIGHT? That's why I told him the correct by the book way to do it. He also did not include WHAT it was in in the original post. DID HE? All I wanted to do was to make DAMN SURE he knew what was going on. We've already come to the conclusion all he is doing is a timing chain replacement and he never messed with the distributor, so dot to dot is fine. Or DID YOU MISS THAT in your quest at smartassary?
 
RustyRatRod said:
WTF? How did we know what he was doing from his original post? If he was building an engine, he would need to stab the distributor, right. Right? RIGHT? That's why I told him the correct by the book way to do it. He also did not include WHAT it was in in the original post. DID HE? All I wanted to do was to make DAMN SURE he knew what was going on. We've already come to the conclusion all he is doing is a timing chain replacement and he never messed with the distributor, so dot to dot is fine. Or DID YOU MISS THAT in your quest at smartassary?
Click to expand...
Go get-em Tiger.
 
Dot at 12 O'clock camshaft
Dot at 12 O'clock crankshaft

Number one up on TDC compression stroke.

Rotor in distributor pointing to #1 plug wire in cap.

Make sure there is gas in the carb, and fire that bad boy up.

Screenshot_20210721-163435_Gallery.jpg

Fuel pump Eccentric Hanging lower left.

Screenshot_20210603-092743_Gallery.jpg


Pointing to fire on #1.

☆☆☆☆☆
 
George Jets said:
Dot at 12 O'clock camshaft
Dot at 12 O'clock crankshaft

Number one up on TDC compression stroke.

Rotor in distributor pointing to #1 plug wire in cap.

Make sure there is gas in the carb, and fire that bad boy up.

View attachment 1716042331
Fuel pump Eccentric Hanging lower left.

View attachment 1716042327

Pointing to fire on #1.

☆☆☆☆☆
Click to expand...
Except that is a HELL of a lot harder to (see) line up when you are hanging from ankle straps from the rafters, fighting a greasy engine pit of some van/ truck/ etc
 
Oldmanmopar said:
If you hold the chain and sprockets in your hand by the upper sprocket. Align the marks 6 on the top sprocket and 12 on the bottom sprocket . Let it hang. You can turn them any way you want to get them to go on. As long as you don't jump a tooth top or bottom it will be in time . You may have to turn the crank to get the keyways in the right spots to go on but the timing chain will be in time.
Click to expand...
BEEN THERE!!! And there is NOTHING stopping a guy from rolling the thing over 1 turn of the crank or 2 and rechecking them if any question.
 
You must log in or register to reply here.
-

Back
Top