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SB LA TDC #933699 02/21/11 01:38 AM 02/21/11 01:38 AM
Joined: Mar 2005 Posts: 386 Maryland reno340 OP enthusiast
reno340 OP enthusiast Joined: Mar 2005 Posts: 386 Maryland	what is the easiest way to determine top dead center on a Mopar small block? (1972 340 w/ stock electronic distributor) Just researching in case I need a new cam? "There are only three real sports, Mountain climbing, Bull Fighting and Auto Racing. The rest are just games" - Earnest Hemmingway If you can't run with the big dogs, stay on the porch!! https://www.youtube.com/watch?v=_xQJtN1_6DU

Re: SB LA TDC [Re: reno340] #933700 02/21/11 04:25 AM 02/21/11 04:25 AM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	If you are using this to install a cam,no need, installing teh gears according to marks will take care of itself. When done you can take out number 1 plug and slowly turn the engine over till you feel compression then very slowly bring up so that the mark is at TDC to install the distributor.

Re: SB LA TDC [Re: MoparforLife] #933701 02/21/11 09:33 PM 02/21/11 09:33 PM
Joined: Mar 2005 Posts: 386 Maryland reno340 OP enthusiast
reno340 OP enthusiast Joined: Mar 2005 Posts: 386 Maryland	Are you talking about the mark at the harmonic balancer? If so, does it point to the 0 on the timing cover? "There are only three real sports, Mountain climbing, Bull Fighting and Auto Racing. The rest are just games" - Earnest Hemmingway If you can't run with the big dogs, stay on the porch!! https://www.youtube.com/watch?v=_xQJtN1_6DU

Re: SB LA TDC [Re: reno340] #933702 02/21/11 10:10 PM 02/21/11 10:10 PM
Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska	Quote: Just researching in case I need a new cam? put the slit on the dampener to the TDC zero mark on the timing tab AND the rotor is under #6 plug wire on the cap. This'll put the crank sprocket dot at 12 0'clock and the cam gear dot at 6 0'clock to match what you'll see in the pic & make for easy lining up the dots w a small steel scale live every 24 hour block of time like it's your last day on earth

Re: SB LA TDC [Re: RapidRobert] #933703 02/21/11 10:31 PM 02/21/11 10:31 PM
Joined: Oct 2010 Posts: 606 Montana Y Yancy Derringer mopar
Yancy Derringer mopar Y Joined: Oct 2010 Posts: 606 Montana	Quote: Quote: Just researching in case I need a new cam? put the slit on the dampener to the TDC zero mark on the timing tab AND the rotor is under #6 plug wire on the cap. This'll put the crank sprocket dot at 12 0'clock and the cam gear dot at 6 0'clock to match what you'll see in the pic & make for easy lining up the dots w a small steel scale Nice try. If he's going to change the cam, it won't matter if the rotor is on no1 or no6, because once you take the cam drive and cam out, you'll be putting it BACK IN at no6, anyhow!!! Look the BEST thing to do is actually CHECK your TDC while you are at it. Use a "piston stop" like this: http://www.jerrybramlett.net/images/pic_installation.jpg You can make, or buy them. Unhook the battery ground, get a wrench on the front crank bolt, and pull out no1 plug. Make sure the piston is down far enough that you can get the stop in. Gently rotate the engine clockwise until it stops. Make a temporary mark under TDC on the timing tab onto the dampener. Do the same counterclockwise. This will leave you with TWO temporary marks. True TDC will be halfway between, and if the factory mark is correct, that is where it will be. Google "cam degreeing" n such, to find out about "degreeing in" your cam. If you are gonna just throw it in there, then you DO NOT REALLY NEED TO KNOW where TDC is, because the "marks" WILL ONLY LINE UP ONE WAY (Actually two) That's with the crank sprocket (they are not gears) at 12 o clock and the cam sprocket at 6 o'clock---the way the "books" show. THIS SET UP no6 ready to fire NOT no1 The obvious second way is with the crank again at 12 o clock and the cam sprocket at 12 o clock --MUCH more difficult to view whether it's a "tooth off" or not. THIS SETS UP no1 ready to fire instead of 6 THE POINT IS, you don't actually need to set the engine on TDC before you tear it down --although probably easier--because when you install the new cam drive, you are FORCED to turn the crank until the mark on the sprocket lines up with the mark on the top sprocket. I STRONGLY SUGGEST you invest yourself in some service / mechanics manuals, and do some Googleing. There are many many articles on installing camshafts http://www.google.com/search?hl=en&s...mp;aql=&oq= MANY of the camshaft manufacturers have 'tech' articles on their websites

Re: SB LA TDC [Re: RapidRobert] #933704 02/21/11 10:32 PM 02/21/11 10:32 PM
Joined: Mar 2005 Posts: 386 Maryland reno340 OP enthusiast
reno340 OP enthusiast Joined: Mar 2005 Posts: 386 Maryland	ahhhhhhh, so when I put the distributor back in it will be at #6 plug wire. How will the oil pump shaft and gear be oriented? "There are only three real sports, Mountain climbing, Bull Fighting and Auto Racing. The rest are just games" - Earnest Hemmingway If you can't run with the big dogs, stay on the porch!! https://www.youtube.com/watch?v=_xQJtN1_6DU

Re: SB LA TDC [Re: Yancy Derringer] #933705 02/21/11 11:00 PM 02/21/11 11:00 PM
Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska	Quote: If you are gonna just throw it in there, THE POINT IS, you don't actually need to set the engine on TDC before you tear it down --although probably easier--because when you install the new cam drive, you are FORCED to turn the crank until the mark on the sprocket lines up with the mark on the top sprocket. My take was that he is wanting to throw a new one in/line up the dots & go rather than finding true TDC/degreeing, Yancy you are starting to become argumentative again live every 24 hour block of time like it's your last day on earth

Re: SB LA TDC [Re: reno340] #933706 02/21/11 11:00 PM 02/21/11 11:00 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	After you install the cam shaft and get the gears isntalled alcordingly. Dot to dot or degreed then go back to square 1 and remvoe the number 1 spark plug and slowly turn the engine over till you feel compression coming out of the spark plug hole and the continue till the TDC marks line up. Now install the intermediate shaft with the slot running parallel to the engine center line. Now install the distributor. The rotor will normally point to the front and center or slightly toward the right front. (I know that a lot of the manuals show and tell it to the left but I have seen the vast majority of virgin small blocks and they usually point to the right front as in my diagram above. Now install the number 1 plug wire in the terminal where the rotor is pointing and follow the firing order around the cap. Actually you can drop the shaft in about any position and have the rotor pointing in about any direction as long as you have tdc and put the number one plug wire where the rotor points and follow the firing order around and you can adjust the timing.

Re: SB LA TDC [Re: reno340] #933707 02/21/11 11:19 PM 02/21/11 11:19 PM
Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska	Quote: ahhhhhhh, so when I put the distributor back in it will be at #6 plug wire. How will the oil pump shaft and gear be oriented? w the crank dot at 12 0'clock and the cam dot at 6 0'clock then index the inter gear so it puts the rotor at #6 plug wire then turn the crank slightly CCW (from TDC to 10BTDC) then turn dist housing till the nearest reluctor tooth is dead even w the magnet w the #6 cap terminal over (or very close to) the rotor tip & your (timingwise)ready to go. live every 24 hour block of time like it's your last day on earth

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