TDC...how the heck...

[Dino]

So I'm trying to figure out where the #1 plug wire goes on my Firecore RTR dizzy.  I know I need to get the #1 piston to TDC but I don't know how.  Everything is installed under the hood minus the radiator.  I don't want to remove too many things if I can help it but will do whatever I need to do.  The damn hardline going from the vapor separator to the carb is hitting one of the studs on the dizzy cap so depending on which direction the plug wire boot points I will probably have to suck up spending hours to fit the damn thing and just get a rubber hose, meaning the alt needs to be pulled yet again.   

The only way I know how to rotate the pistons on this thing is to stick a ratchet on the front...but I don't have a socket that large that will fit.  I removed all the spark plugs but I doubt you can roll this thing by hand right?  So I guess I need to buy a socket?  What size is this monster?

Also when the piston is all the way at the top and the line in the damper lines up with the hole, is that TDC?  I don't have any TDC tools so what do I need to buy to do this right? 

Last one:  When the #1 piston is at TDC, I remove the cap and wherever the narrow end of the rotor points is where the #1 plug wire goes right?

[Dino]

Alright I found out some more.  Looks like I need a 1 1/4" socket so I'll pick that up tomorrow.  Seems a piston stop is the way to do this right so I'll get one of those as well.  If I understand correctly, I screw the piston stop in the #1 cylinder and turn the center of the stop in about 1 1/2".  I rotate the balancer one way until the piston stops, make a mark on the balancer, rotate the balancer the other way, make a mark again and TDC is hallway between the two?

[Cooter]

If all your looking to do is drop in a new distributor, no piston stop needed. If your degrading a cam, then I could see it.
simple way to find TDC. Have a buddy bump engine over with number one plug out and find very in hole. When a gust of air begins to knock your finger out of hole, STOP. Rotate engine rest of way around by hand until line on balancer lines up with "O" on timing tab.

If you haven't ripped your original distributor out yet, even quicker way is to look where number one cylinder. Wire is on cap, remove cap and see how far away Roto button is away from that tower. Bump around till button is lined up near that tower in cap.

[cudaken]

Believe it or not, when finding TDC on Miss Lumpy (68 Road Runner that sat 8 years) while rotating with a breaker bar I could feel the compression with my finger. 

If you want to check and see if your timing ring as slipped, you need the piston stop.

Ken

[BSB67]

Alright I found out some more.  Looks like I need a 1 1/4" socket so I'll pick that up tomorrow.  Seems a piston stop is the way to do this right so I'll get one of those as well.  If I understand correctly, I screw the piston stop in the #1 cylinder and turn the center of the stop in about 1 1/2".  I rotate the balancer one way until the piston stops, make a mark on the balancer, rotate the balancer the other way, make a mark again and TDC is hallway between the two?

But that does not necessarily mean that the #1 cylinder is firing.  The rotor may be pointing at #1 or #6 cylinder.

[Dino]

This stuff can never be easy can it?   

I haven't been able to find the line on the balancer yet, but visibility is limited so it may come in sight when I rotate it.  I wanted to use the piston stop exactly because I had read on here that the outer rim can slip and give a false reading.  It's a cheap tool so I might as well do it right and then mark the balancer for future reference.  Besides, there's nobody around to help me turn it over so I need to do it myself.

I did remove the old dizzy and stuck the new one in the same way, but I can easily check the old one to see where it was pointing as I simply removed it and stuck it in a box.  I hadn't though of simply comparing them.  I did remove all the wiring on that one but I'm sure I have a few pics around that show where they went.

BSB, is there a way to make sure which one it's pointing at?

Thanks guys.

[Back N Black]

You can turn the engine by hand with the plugs out, no problem. Another option is run a couple of wires from the starter relay connected to a push button to crank while finger in number one hole.

[Dino]

You can turn the engine by hand with the plugs out, no problem. Another option is run a couple of wires from the starter relay connected to a push button to crank while finger in number one hole.

When you say by hand do you mean that literally or with a breaker bar and socket?  I have not released the belt tensioner yet thinking it would not turn by me grabbing the pulley anyway.

I'm still a ways away from putting power to the car so that's not an option just yet but good to know at least!   

[Back N Black]

I mean by hand, reach down between the engine and rad, grab the crank pulley with two hands and turn the sucker! 

[Dino]

I mean by hand, reach down between the engine and rad, grab the crank pulley with two hands and turn the sucker! 

No  kidding!  I'll have to loosen the belts then because when I try that now it's not budging at all and all the plugs are out.

[ottawamerc]

Wow you would have to have a grip like superman to spin mine I had to use a socket and ratchet and still there was a good amount of force required to move it even with all the plugs out. Dino if you do install the piston stop please make sure you remove your negative battery cable, I think you said there was now power in your car yet anyways but is you crank the engine with the starter with a stop in there there goes your piston! Only by hand.

Scott

[myk]

Hmmm....I don't get it.  If all you're doing is just replacing a distributor, couldn't you just clock the rotor/shaft on the new dizzy to match the one already in the car, remove the old unit, and then drop in the new one? 

[68 RT]

Hmmm....I don't get it.  If all you're doing is just replacing a distributor, couldn't you just clock the rotor/shaft on the new dizzy to match the one already in the car, remove the old unit, and then drop in the new one? 

I agree with that! 

[Dino]

Hmmm....I don't get it.  If all you're doing is just replacing a distributor, couldn't you just clock the rotor/shaft on the new dizzy to match the one already in the car, remove the old unit, and then drop in the new one? 

I dunno, can I?  I can certainly look at the old dizzy and match the new one to it.

Wow you would have to have a grip like superman to spin mine I had to use a socket and ratchet and still there was a good amount of force required to move it even with all the plugs out. Dino if you do install the piston stop please make sure you remove your negative battery cable, I think you said there was now power in your car yet anyways but is you crank the engine with the starter with a stop in there there goes your piston! Only by hand.

Scott

Yep, no power to the car and all the plugs are out.  This baby ain't doing the vroom vroom today!   

[Cooter]

If all your looking to do is drop in a new distributor, no piston stop needed. If your degrading a cam, then I could see it.
simple way to find TDC. Have a buddy bump engine over with number one plug out and find very in hole. When a gust of air begins to knock your finger out of hole, STOP. Rotate engine rest of way around by hand until line on balancer lines up with "O" on timing tab.

If you haven't ripped your original distributor out yet, even quicker way is to look where number one cylinder. Wire is on cap, remove cap and see how far away Roto button is away from that tower. Bump around till button is lined up near that tower in cap.

Hmmm....I don't get it.  If all you're doing is just replacing a distributor, couldn't you just clock the rotor/shaft on the new dizzy to match the one already in the car, remove the old unit, and then drop in the new one?  

[Dino]

I removed the old dizzy months ago so I have no clue which wire it was pointing to.  I have pictures that show where the wires were on the cap but without knowing where the rotor was pointing to that's not going to do me any good.  Of course no parts stores around me even have a piston stop so now I have to order one.

Is this one alright?

http://www.ebay.com/itm/TDC-Piston-Stop-Top-Dead-Center-Stop-Tool-/121351588500?hash=item1c411e4a94&item=121351588500&pt=Motors_Automotive_Tools&vxp=mtr

[Troy]

I use a "remote" switch to bump the starter.  Very cheap and I don't have to keep climbing in and out of the car. I have a piston "stop" that actually has a spring and a gauge so you can see it rise and fall. Normal stops actually stop the piston so you'd want to be hand cranking. I use a long breaker bar and socket for that. In the old days, I used a screwdriver while someone else cranked. Super simple idea that works fine - until you get it cocked in there sideways! With the plugs out you can definitely hear the escaping air of the compression stroke - or you can cover the hole with a finger and it will get pushed off.

The distributor itself can be in any position - just make sure the #1 wire is pointing to the post that your rotor is on when #1 is at TDC. Ideally, if you have a vacuum can, it is toward the engine facing slightly forward and there's enough room to rotate it to adjust the timing. FYI - #6 will also be at TDC at the same time (just on the exhaust stroke) so if it's easier to reach then use it. I set the timing using the #6 wire fairly often since the timing mark on the crank will be at the same location (two camshaft revolutions per crank revolution).

Troy

[firefighter3931]

Dino,

You don't need a piston stop to get the emgine at TDC.  The procedure outlined above using the piston stop is how you check indexing on the harmonic balancer. 

-Pull all the plugs
-Rotate the engine so that the timing mark lines up the zero mark on the timing cover tab
-Check to see if #1 piston is at the top of the bore. If it is....you're at TDC. You can use a small piece of wire through the sparkplug hole to feel for the piston. If the piston is not up top....rotate the engine 360* and check again.
-Once you've set #1 to TDC install the distributor and clock it so that the vac advance is paralell to the front of the engine....this will allow for for/aft movement to adjust the timing.

* I like to advance the timing to 15* BTDC then install the distributor with the rotor lined up at #1 on the cap. This gives you your initial timing allready dialed in and makes the engine easier to fire.


Ron

[myk]

Dino,

You don't need a piston stop to get the emgine at TDC.  The procedure outlined above using the piston stop is how you check indexing on the harmonic balancer. 

-Pull all the plugs
-Rotate the engine so that the timing mark lines up the zero mark on the timing cover tab
-Check to see if #1 piston is at the top of the bore. If it is....you're at TDC. You can use a small piece of wire through the sparkplug hole to feel for the piston. If the piston is not up top....rotate the engine 360* and check again.
-Once you've set #1 to TDC install the distributor and clock it so that the vac advance is paralell to the front of the engine....this will allow for for/aft movement to adjust the timing.

* I like to advance the timing to 15* BTDC then install the distributor with the rotor lined up at #1 on the cap. This gives you your initial timing allready dialed in and makes the engine easier to fire.


Ron

Ron, what about the drop-in method I mentioned above?  Would that have worked if Dino still had his old distributor installed?

[BSB67]

-Rotate the engine so that the timing mark lines up the zero mark on the timing cover tab
-Check to see if #1 piston is at the top of the bore. If it is....you're at TDC. You can use a small piece of wire through the sparkplug hole to feel for the piston. If the piston is not up top....rotate the engine 360* and check again.
-Once you've set #1 to TDC install the distributor and clock it so that the vac advance is paralell to the front of the engine....this will allow for for/aft movement to adjust the timing.

If the timing mark is at zero on the timing tab, the #1 piston WILL be at TDC.  And of course, if you rotate it another 360°, it will still be at TDC.

What he needs to determine is if it is on compression or overlap.

[Cooter]

If all your looking to do is drop in a new distributor, no piston stop needed. If your degrading a cam, then I could see it.
simple way to find TDC. Have a buddy bump engine over with number one plug out and find very in hole. When a gust of air begins to knock your finger out of hole, STOP. Rotate engine rest of way around by hand until line on balancer lines up with "O" on timing tab.

If you haven't ripped your original distributor out yet, even quicker way is to look where number one cylinder. Wire is on cap, remove cap and see how far away Roto button is away from that tower. Bump around till button is lined up near that tower in cap.

Hmmm....I don't get it.  If all you're doing is just replacing a distributor, couldn't you just clock the rotor/shaft on the new dizzy to match the one already in the car, remove the old unit, and then drop in the new one?  

[six-tee-nine]

If you rotaded the crank for about 50 times its easy to know when the #1 piston is at tdc but you still need to know how the positoin of the valves of the #1 cilinder.

If you really are unsure, pull the valve cover so you can see when the valves are closed.

Normally the 0 mark on the balancer should give you the correct position anyway

[Dino]

The mark on the balancer is a split right?  I just picked up the socket so I'll give it a spin tonight and see what I can find.  As it sits now, I don't see any marks.

[firefighter3931]

-Rotate the engine so that the timing mark lines up the zero mark on the timing cover tab
-Check to see if #1 piston is at the top of the bore. If it is....you're at TDC. You can use a small piece of wire through the sparkplug hole to feel for the piston. If the piston is not up top....rotate the engine 360* and check again.
-Once you've set #1 to TDC install the distributor and clock it so that the vac advance is paralell to the front of the engine....this will allow for for/aft movement to adjust the timing.

If the timing mark is at zero on the timing tab, the #1 piston WILL be at TDC.  And of course, if you rotate it another 360°, it will still be at TDC.

What he needs to determine is if it is on compression or overlap.

Correct....it needs to be on the compression stroke with #1 firing.


Ron

[firefighter3931]

The mark on the balancer is a split right?  I just picked up the socket so I'll give it a spin tonight and see what I can find.  As it sits now, I don't see any marks.

Yes, there should be a groove on the balancer. Use some white paint to make the mark easier to see when you go to time the engine. 


Ron

[firefighter3931]

Dino,

You don't need a piston stop to get the emgine at TDC.  The procedure outlined above using the piston stop is how you check indexing on the harmonic balancer. 

-Pull all the plugs
-Rotate the engine so that the timing mark lines up the zero mark on the timing cover tab
-Check to see if #1 piston is at the top of the bore. If it is....you're at TDC. You can use a small piece of wire through the sparkplug hole to feel for the piston. If the piston is not up top....rotate the engine 360* and check again.
-Once you've set #1 to TDC install the distributor and clock it so that the vac advance is paralell to the front of the engine....this will allow for for/aft movement to adjust the timing.

* I like to advance the timing to 15* BTDC then install the distributor with the rotor lined up at #1 on the cap. This gives you your initial timing allready dialed in and makes the engine easier to fire.


Ron

Ron, what about the drop-in method I mentioned above?  Would that have worked if Dino still had his old distributor installed?

Yep, that would work fine as long as the rotor was lined up with the correct tower on the cap. I've seen some MP distributors that were not phased properly as compared to stock.

I prefer to start from scratch and time it using established procedures. 


Ron

[Dino]

Good plan!  I  have a white paint pen that should do the trick.  Do I mark anything on the timing mark plate itself to making setting the timing easier?

If the split lines up with the zero mark, can it still be on the overlap stroke?  Ie do I have to pull the valve cover to make sure?  I don't mind doing so if it gives me the security.  I'd like to install the new plug wires only once if possible.   

[firefighter3931]

Marking the scale on the timing cover tab will definately make it easier to read with the timing light 

Removing the Valve cover will definately make things easier or you can bump the engine over at the starter relay with your finger over the #1 spark plug hole. Either way will work 


Ron

[myk]

Dino,

You don't need a piston stop to get the emgine at TDC.  The procedure outlined above using the piston stop is how you check indexing on the harmonic balancer. 

-Pull all the plugs
-Rotate the engine so that the timing mark lines up the zero mark on the timing cover tab
-Check to see if #1 piston is at the top of the bore. If it is....you're at TDC. You can use a small piece of wire through the sparkplug hole to feel for the piston. If the piston is not up top....rotate the engine 360* and check again.
-Once you've set #1 to TDC install the distributor and clock it so that the vac advance is paralell to the front of the engine....this will allow for for/aft movement to adjust the timing.

* I like to advance the timing to 15* BTDC then install the distributor with the rotor lined up at #1 on the cap. This gives you your initial timing allready dialed in and makes the engine easier to fire.


Ron

Ron, what about the drop-in method I mentioned above?  Would that have worked if Dino still had his old distributor installed?

Yep, that would work fine as long as the rotor was lined up with the correct tower on the cap. I've seen some MP distributors that were not phased properly as compared to stock.

I prefer to start from scratch and time it using established procedures. 


Ron

My 90's era MP distributor has a phase problem: the terminals inside the cap have the ignition burn-mark not on center but off to the side of the terminal.  I'm surprised the engine fires at all...

[Tilar]

10 minute job... Pop the valve cover off over the number 6 cylinder, roll the engine over to the point where you see the exhaust valve on #6 closing and the intake valve on #6 starting to open. Roll the crank to the point where both valves are open the same amount (won't be much) and that will put #1 cylinder at TDC on the compression stroke. Mark your balancer and timing cover if there isn't already a mark, reinstall the valve cover and pop a top on a cold one. 

Yeah this might have been mentioned earlier but I haven't read all the replies.

[BSB67]

Personally, for fast, easy and works every time, I'd go finger in the hole.

[Dino]

I should have a bit of time this weekend to do this.  Finger in the hole will still be a bit hard seeing I'm doing this alone but if I find a victim to help I'll try it. 

I just replaced the valve cover gasket and bolts on the passenger side.  Do I have to pull it back off to check the valves or can I do this with the ds cover removed?  I haven't changed that gasket or bolts yet. 

I don't know anything about valves so I'll have to spend some time looking up what the heck you guys are talking about.   

[Tilar]

If you use the method I mention you would have to pull that valve cover back off, because #6 piston moves in exact relation to #1 making #6 between the exhaust and intake stroke where #1 will be between the compression and power stroke. If you can figure out which valve is the exhaust valve on #6 cylinder, as you bump your engine over you will see that valve open and then close as you turn the engine, when the exhaust valve comes back up there will be a point right as it closes that both valves should be open just a little as the intake valve starts to open. That is the position where your #1 piston is at Top Dead Center of the compression stroke.

It's the easiest way I know of if you're doing it by yourself and you want to be exact. You can rig up a momentary on push button switch and a couple wires (remote start button) hooking it up to the starter relay and just bump the engine over with your finger over the hole, but you're not going to feel the exact position with your finger unless you can see the timing marks.

[Dino]

Alright I'll pull the ps cover again.  I want to do this right.  Thanks!   

[Tilar]

 

[cudaken]

Alright I'll pull the ps cover again.  I want to do this right.  Thanks!   

What the heck is a ps cover?  Power Steering?

Dino, you are making this way harder than it needs to be!

Ken

[Dino]

Passenger side.  We were talking about the valve cover.

I literally only had a few minutes this weekend so I stuck the socket on the crank pulley and turned so the slit on the dampener was on the zero mark.  I can feel the piston with a wooden dowel but can't say If it's all the way at the top.  Unless there's another way to make sure it is TDC at the compression stroke, I'm pulling that valve cover again sometime this week.

[NHCharger]

Dino. Just have someone turn the engine while you check for #1 to come to TDC. I had my son turn the engine while I stuck a wire into the plug hole to feel the piston at TDC.

[myk]

Dino. Just have someone turn the engine while you check for #1 to come to TDC. I had my son turn the engine while I stuck a wire into the plug hole to feel the piston at TDC.

But...the piston could either be on the compression or the exhaust stroke...

[Dino]

I need to do this by myself.  I can turn the engine a bit with a wrench and feel for the piston, but I can't so it at the same time.  If I need to do this by watching the valves then that's what I'll do, no biggie.   

[b5blue]

Get or make a remote starter switch Dino!
http://www.harborfreight.com/12-volt-remote-starter-switch-35448.html
Just jump the starter relay and tap the switch. 

[cudaken]

Get or make a remote starter switch Dino!
http://www.harborfreight.com/12-volt-remote-starter-switch-35448.html
Just jump the starter relay and tap the switch. 

Dino, I used a remote switch as well. Put your finger over the hole and start bumping the starter. When I felt some compression in #1 I just cranked the motor rest of the way by hand till it was on TDC using the timing ring. It took me a whole 5 minutes? 

I did use a long 1/2 drive socket and breaker bar so that helped.

Ken

[71 SE3834V]

Dino, I told you to let me know.
I've got a remote start button, socket set up to 2", breaker bars, compression testers, fingers, timing lights and time. Been there, done this many times.

[71 SE3834V]

I'll tell you what, I'll help you find TDC and you can help me replace my cam. Ugh!

[maxwellwedge]

Personally, for fast, easy and works every time, I'd go finger in the hole.

x300!  

Get a friend or a cheap remote starter switch to bump the engine over with the starter motor.  
pull the coil wire to make sure the mill doesn't fire.
stick your finger in #1
Bump the engine a tick at a time until you feel the compression trying to knock your finger out of the hole....you will know when it happens!
Look at the timing mark on the dampener. Should be coming close to the degree marks on the timing cover. Spin the engine a tick more (better with a socket at this point) until the mark lines up with "0"
Make sure your dizzy gear is indexed so the slot is more or less parallel with the centerline of the engine. Pop in your dizzy. Your rotor position will now be at #1

This should get you close enough to fire....you may need to twist it a tick each way.
Fire it. Time it. Lock it down, burn rubber.  

[Dino]

Hey guys, car work time has been very limited but I'm trying to catch up.  School's almost over, a few more exams and I'm done for a while.

If need be I can rig up a remote starter switch from parts I have.  

71 SE3834V I had forgotten about your offer, sorry and thanks!  

If you need help with a cam I'm happy to help, but I know squat about it so don't expect too much.  

I'm going try the finger trick first, and I may just pull the valve cover again.  There's really no way to tell the compression stroke of #1 by looking at the drivers side valves?

[71 SE3834V]

You can tell you're on the compression stroke when the #1 rockers are no longer moving but you won't be able to tell if you're exactly on TDC unless you can see the piston through the plug hole or looking for the timing mark on the damper assuming it hasn't moved.
I would hook up a remote start button, put finger on hole, (I wasn't going to touch the above statement about finger in hole), bump starter until you feel compression, then look at the damper and you should be able to see the mark just CCW of the 0 on the scale. At this point use socket to roll engine to align up the mark. Might have to work underneath but I understand you have the rad out see it's easy from the topside. Put white paint on the mark. Very helpful when using timing light.
Don't over think it. In the time it took to write all this it coulda been done.

No knowledge needed to help me. Sometimes having someone to just clean parts is a big help. If you're interested in learning some things let me know. I know you're busy so my bargin was in jest. My offer is still good!
I just confirmed yesterday I have a wiped out cam. Now I've opened a can of worms as far as "how far do I go in this project".   I just wanted a car I could drive around and have a little fun with. I already have one in my '72 Galaxie but it's no "Charger"! I'll have to start a thread about my sad sack story so I can get some advice/encouragement/costs to help me figure this out.

[Dino]

I took the ds valve cover off, I needed to replace the gasket.  I had put the mark on the dampner on the zero mark a while ago.  I started turning the crank and the #1 rockers initially didn't move so I must've been on the power stroke already.  I kept turning, the rockers moved and once they stopped I could just see the dampner mark coming up so I kept turning a bit until it reached zero and the rockers did not move.  Did I find it?

[71 SE3834V]

Yep! Easy wasn't it?

[Dino]

Yep! Easy wasn't it?

It felt a bit too easy so I'd thought I'd ask.   

The dizzy rotor points to about 5 o' clock, the same spot as my old dizzy so that seems to work out nicely.

Alright, lemme get the valve cover back on!   

Thanks for all the help peeps, I sincerely appreciate it.