TDC identification

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SVO2SCJ

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Looking at a 1972 351C balancer LIKE THIS.....it goes ATC 10 Then 6 hashmarks and O (zero). So from comparison it looks like you are a about 12 Degrees BELOW in that photo.

Either sand it clean so you can see better, or use my info back up and LOOK AT THE DISTRIBUTOR ROTOR (in relationship to number one). We don't know IF your distributor has been clocked before, IF you have removed already SO this needs to be done correctly.

Hopefully you haven't pulled the distributor yet....so you have put at TDC, confirm number one on the cap and install new distributor. Don't be afraid to call 5178617630

Mark

 

Fabrice

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if you install a new dist and have rotated the engine(or have not looked at where the dist pointer pointed before remove it), keep in mind, it will pass the 0 mark twice for a full cycle.

So you must be sure the 0, correspond on the compression stroke of cyl #1. An easy and quick way to find out is when just before btc, close cyl#1 plug hole with your finger. If you feel pressure, at 0, its TDC, if not, you need rotate the engine another 360 degrees.

Insert the dist gently and in last bits, use the pointer to turn the dist axle a bit so it finds its way into the cam gears.

With your strobo light ready (all plugs removed), crank the engine and check timing, +-10deg so it can start.

Then using firing order 13726548 ccw, put your plugs backs and set the wires. Check vacuum lines/or block them and try start..

 

Andy 351C

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[url=https://ibb.co/nHuFMR][img]https://preview.ibb.co/mjKh1R/IMG_5067.jpg[/img][/url]
Thanks guys for responding. I haven’t removed the distributor yet. I don’t have anyone to help me crank the engine unfortunately, but the rotor is pointing to the number one spark plug wire on the distributor cap, also I checked with a straw and the piston seams to be in the highest position when sticking the straw in the the number one spark plug hole. I Think it would be best to clean the balancer better and get a better picture. I guess I was hoping someone would recognize the orientation right off the bat. Thanks again for your help.

 

libram

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can clearly see in the image you're at TDC, I can count ten hash marks to the mark that reads 10 ATC

 

deford1

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Thanks guys for responding. I haven’t removed the distributor yet. I don’t have anyone to help me crank the engine unfortunately, but the rotor is pointing to the number one spark plug wire on the distributor cap, also I checked with a straw and the piston seams to be in the highest position when sticking the straw in the the number one spark plug hole. I Think it would be best to clean the balancer better and get a better picture. I guess I was hoping someone would recognize the orientation right off the bat. Thanks again for your help.

You can purchase a bump start from your local parts house fairly cheap. It's like having a second set of hands.

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Andy 351C

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[url=https://ibb.co/nHuFMR][img]https://preview.ibb.co/mjKh1R/IMG_5067.jpg[/img][/url]
Thanks, I counted the ten hash marks as well and was fairly confident, but not certain I was at TDC. Still going to clean it up a bit more. I will definitely invest in a remote starter, great advice. Found one at summit racing for $12. There is about 3/8” - 1/2” of rotational play turning my rotor, so I’m thinking the gears my be worn, plus I can’t start the engine anymore. So I’m trying to get things perfect. Upgrading to a pertronix electronic distributor.

 

jeff8877

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Andy,

Take a piece of steel wool or sand paper to the balancer and get off the surface crap. Then take a piece of chalk and rub it on, then wipe off lightly with rag. The white chalk will fill in the grooves and you will be able to read.

 
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Thanks, I counted the ten hash marks as well and was fairly confident, but not certain I was at TDC. Still going to clean it up a bit more. I will definitely invest in a remote starter, great advice. Found one at summit racing for $12. There is about 3/8” - 1/2” of rotational play turning my rotor, so I’m thinking the gears my be worn, plus I can’t start the engine anymore. So I’m trying to get things perfect. Upgrading to a pertronix electronic distributor.
 Just my opinion based on what I've learned from my own experience with timing, but I wouldn't waste my money on a Pertronix distributor. My local auto parts store has dropped that line because of too many issues with them. Not to say there have not been improvements since, but I think I would lean toward a reman Motorcraft or Cardone Select new Ford (style) dizzy with a Pertronix Ignitor II module and matching coil. DO NOT be tempted to go with an Ignitor III in a Ford. Unless Pertronix have redesigned the mechanical "bearing" between the two plates, you will have timing problems. I have posted on my experience many times on this. In my case Pertronix took it back and replaced the III with a II and coil and after learning how to rebuild and recurve the distributor to run 16* of initial mechanical timing, I couldn't be happier. I think the problem with most timing on 351C's is they were set retarded at 6* for emissions reasons, when in fact they need much more initial. HO engines were set at 16*.

I'm not sure what you have engine wise, but there is a lot more to getting timing right than meets the eye. I learned the hard expensive way, which is why I tend to be a bit hard on others. All I'm saying is be careful, do your homework, ask a load of questions from the much more experienced guys here before you dive in and start pulling that distributor out.

Again just from my timing wows, the reman. Motorcraft I bought was built for an initial of 6* as the limit slot was called an 15L, which equates to 30 degrees on the crank. If you want to run 14-16 degrees of initial, the max mechanical advance is 34-36 degrees, which means you only need 20 degrees on the crank or an 10L limit slot. I actually stripped my distributor and welded the slot and recut it to give me the required advance,. That slot width is .410". If yours has an 13L slot, you might get away with using a small piece of 3/16" nylon tube slipped over the post, which will do much the same thing and far simpler.

Hope that didn't scare you too much, but it is very important to get it right and I'm afraid a lot of these so-called drop-in aftermarket distributors are far from plug-n-play.

I'm posting a picture of a cam showing a 15L slot and a Cardone Select that I did as a back-up so you can see the limit slot. Next is springs and tension to get the curve just right, but that for later maybe.

EDIT: I didn't mention that my 351 C 4V with only 10:1 pistons still had a lot of spark rattle on 91 octane fuel before I corrected the amount of mechanical advance. I also only put in about 6* of vacuum advance. I ditched the dual vac canister as the retard side (rear tube) is not needed. It pulls up to 6K now with no rattle.

 
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SVO2SCJ

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What do you mean "I can't start my motor anymore?!" Are you saying "car won't start" .....so you FIGURED you would replace the distributor?

When I first read this I assumed you had a running car and just wanted to get away from the points etc etc. BEFORE you start throwing parts at the car, what did you do to confirm spark/fuel? Has this been a running car, complete AS IN put in key and turn to start? (A little more info, even PHOTOS or video of engine condition will go a long way to SEEING what you have)

Mark

P.S. Sorry about using a 1972 balancer in my counting of hash marks - 72 seems to use 2 each where as the 73 is every degree

 

Andy 351C

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That is a ton of information to absorb and I can’t tell you guys how much I appreciate the help. It is not the original motor and very well may be a 1972 motor. The previous owner said the heads were from a 1972 and it has square top pistons for a bit more compression. The car ran excellent when I bought it with plenty of power. I drove it 150 miles to get it home and the performance slowly declined to the point now where it won’t start. Started dieseling real bad and I had to shut the car off in drive or it would never stop. It started knocking bad on acceleration like the timing was way off. I took it to a mechanic and he gave me a list of things to upgrade including the distributor and coil. He wanted to pull the heads off and investigate burnt valves, but I didn’t want to throw that kind of money at it yet. The owner said the engine only has 17,000 miles since it was rebuilt. I’m replacing things that I feel comfortable with and that was recommended to me by the mechanic.

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That is a ton of information to absorb and I can’t tell you guys how much I appreciate the help. It is not the original motor and very well may be a 1972 motor. The previous owner said the heads were from a 1972 and it has square top pistons for a bit more compression. The car ran excellent when I bought it with plenty of power. I drove it 150 miles to get it home and the performance slowly declined to the point now where it won’t start. Started dieseling real bad and I had to shut the car off in drive or it would never stop. It started knocking bad on acceleration like the timing was way off. I took it to a mechanic and he gave me a list of things to upgrade including the distributor and coil. He wanted to pull the heads off and investigate burnt valves, but I didn’t want to throw that kind of money at it yet. The owner said the engine only has 17,000 miles since it was rebuilt. I’m replacing things that I feel comfortable with and that was recommended to me by the mechanic.

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 Andy, not saying the guy you got it from is full of sh*t, but just looking at your picture, it has a lot of crap on it for a relatively 'new' motor, unless there was an oil leak on the front seal or somewhere close by. It just looks off to me as well with the amount of paint crud on the balancer. If by chance you ever have the starter off, the block casting code and date code is just above that location. That will tell you at least what original date of that block was. Post a pic and someone will ID it for you. The head date codes are between the valves and easily seen, however, the head casting ID are under the intake ports and needs the intake off to see them with a mirror. A real PITA!

As Mark said, figure one thing out at a time, don't rush into replacing anything till you know what the issue is. Can you take a short video of the movement you say there is on the points rotor. It should be no more than the advance movement. If it's a load more I would think the drive gear could be f'd, but not sure.

 
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Justin71

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can clearly see in the image you're at TDC, I can count ten hash marks to the mark that reads 10 ATC
I'm not sure I see the same thing.  I also believe the hash marks are 2deg increments.  On the right hand side of the image, I see another 10 deg mark (had to zoom in to see) but I interpret this position to be 10 degs below TDC...  Looks to me like the marker is directly over the 10 BTDC mark.  This would be consistent with 2deg increments on the smallest hash marks.



Really suggest you get clearer readings on the damper before proceeding.

 

Don C

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It may be at TDC, but it also has to be on the compression stroke, and not the exhaust stroke, for distributor timing.

 

libram

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you might be right there is a faint line that may be a 1 in front of the 0 in the top right corner, it could also be dirt lol

 

sciabola13

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I would clean and mark the timing marks, pull the plugs and cycle the engine by hand to make sure. A little bit of effort up front will save a ton of frustration. I am just getting motor up and running on my 71, 351C. Running stock dizzy with a pertronix 2, and coil. Had a great result with that setup so far. Haven’t drove car yet, but the upgrade made her fire up and idle way better than before.

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SVO2SCJ

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OK ..........Well good for you for admitting you have to learn, get your arms around this and THEN make a plan. As stated , you will have to figure out WHAT you have (just from a stand point of knowing what parts to order moving forward) as well as condition.

A PHOTO of the whole thing - goes a long way as the the THINGS we with 40+ years of working on Fords can see. (don't be embarassed as to look, as that is ALSO part of the "how many miles". Forensically you can tell 17K from 117K , "current condition" might take compression test, timing confirmation or EVEN internal problems (like stripped timing gear if original) distributor issues or "burnt valves" (as your friend said) BUT that would mean KNOWING what valve train you have! (Let's not until we know WHAT you have).

Mark

P.S. My guess is there are people close to you that can help too -- IF I wasn't driving to AZ for auctions but FL I would stop by!

 

Andy 351C

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Great advice all around, especially not to not cut any corners. I tend to get in a hurry. I won’t be working on it till after the new year, but I’m so pleased with this group and how helpful you all are. Looking forward to hearing mine idle again! Merry Christmas you guys.

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SVO2SCJ

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Great advice all around, especially not to not cut any corners. I tend to get in a hurry. I won’t be working on it till after the new year, but I’m so pleased with this group and how helpful you all are. Looking forward to hearing mine idle again! Merry Christmas you guys.

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Ok WE tend to think that many work on cars 365 days a year!! It how you do a car a year or so! (Have always said "an hour a day no more NO LESS" ! Merry Christmas - I will take tomorrow off (kind of getting stuff ready for January Swap meet) ! LOL

 
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