318 TDC help

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BigBlockMopar28

BigBlockMopar28

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Got a new distributor for the 318, current dist timing is no good. Is there any way to find tdc in a 318 by just using the crank dampener and the rotor button location? On my crank dampener i have 2 sets of 2 yellow lines, one goes all the way across the dampener edge, the other set only goes halfway across the edge or so, dunno if that is by design or wear, also dont know if they have different meanings. What i've been told is that the 2 yellows going all the way across mean tdc on piston #1, just dont have anybody around atm to bump the starter around to compression stroke then hand crank to the lines, hence the rotor button question lol. TIA
 
You can do the cork in the sparkplug hole trick and turn it over with a breaker bar on the front crank bolt until the cork pops out. The will be Tdc compression.
 
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You are on the right track. Someone marked the lines yellow. From the factory, the indented line that goes all the way across is TDC ( top dead center for cylinder #1). The smaller indented lines can occur on either side of the TDC mark. On one side of the TDC line these partial lines mean 2 degrees, 4 degrees, 6 degrees, 8 degrees and so on. Depending on which side of TDC these lines are found, these small lines will be BTC ( before top dead center) or ATC (after top dead center). You should clean up the damper so that you can clearly see these lines. Even sandpaper. The procedure for orienting your distributer - #1- remove #1 spark plug. #2- with your finger covering that hole, bump the starter slowly until you feel a large puff of air coming out of that hole. It will not hurt you, this is the piston coming up on the compression stroke. #3- look down on your damper and you should see the large line ( TDC) very close to the pointer. Turn the engine so that TDC and the pointer are aligned. Congratulations, your engine is now at TDC. #4- locate #1 spark plug wire on your distributer cap. Remove cap, is the rotor pointing at #1 wire? If not, then remove the distributer and set back in to point to that wire. This should be close enough now to start the motor. Always follow up with a timing light to confirm. Hope this helps.
 
YUP. Pistons stop. This is one I made in the early 70's and still have it

stop2-jpg.jpg


If you buy one be certain to add a lock nut to jam the plunger. the popular ones you see "wiggle around."

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Remove battery ground, and no1 plug. Look in or probe the cylinder to make sure the piston is "down a ways." Install the stop. Use a socket to rotate the crank CW until the piston stops on the device. Make an accurate temporary mark onto the balancer under TDC

Now rotate all the way around CCW until it again stops. Make a second mark. The TRUE TDC will be halfway between the two marks

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There are only two ways to get the dist installed on the correct stroke. It does not matter where the intermediate gear is, and distributor tangs turn out "they vary" over the years, IE the tang is not always the same relationship as the rotor

So..

A: If you have either valve cover off, bring the engine to TDC. Either no6 or no1 valves will be closed, the other two will be close to "split overlap" IE both somewhat open. BE CAREFUL they are easy to mistake. Turn the crank a few degrees, if either valves move, you are on the wrong stroke.

B: Remove no1 plug, devise a way to jumper the starter AT THE STARTER RELAY, all you need is a screwdriver across the two large exposed terminals.

Stick a finger in no1, bump the starter until you feel compression

Now look for the marks "coming up." Bump or wrench the engine around until you get the marks to NOT TDC, but rather where you want initial timing, IE 8-10 for a bone stock 318, 15 or so for a mild cam, might be more on a real thumper.

So NOW you have the engine ON THE correct stroke (no1 compression) and you have the MARKS set NOT at TDC, but where you want initial timing.
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NOW drop in the distributor. You do NOT have to use a special hole for no1. Put the rotor pointing the one of two ways it will fit, rotor pointing to driver's side.

Rotate the dist. body "retarded" (CW on a SB). Slowly bring it back advanced (CCW) until the points just open or the reluctor is centered in the pickup core

YOU CAN ALSO use a timing light "on the starter" to set timing!!

Use the cap and determine which tower the rotor is "about to" connect going CW. Plug no1 into that hole and then the rest of the wires..........and......

START IT UP
 
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You might read my thread on "test firing" a magnum. "It's just that easy." READ POST 19

Bear in mind this is a quickie temporary test, and because of the "beer keg" I was not able to install the dist with the vacuum over on the pass side.

LMFAO Anybody figure out what this is?

Due to the absolute **** CRAP "improved software" on this forum, a person is NO LONGER ABLE (at least not easily able) to post a specific post independently. The OLD software did this EASILY.
 
Another useful tool. This is an engine test fire ignition, or emergency roadside ignition. It's a GM HEI "in a box." Hoop up ground, batter clips, plug in the coil wire and dist. pickup, and off you go. I use it for test firing used engine like the one below. NO! You don't need manifolds, LOL, and I've done it with NO carburetor, just throw a little gas in the manifold!!

hwlcfa.jpg


34nf6l0-jpg.1715060533

34nf6l0-jpg.jpg
 
I remove the #1 spark plug, put thumb over hole and crank engine over with a screwdriver at the starter relay feeling for compression, to align the slot in the damper at 10 degrees advance. drop distrib. in with rotor aligned with #1 plug wire in distrib. cap
 
So i confirmed compression stroke on #1, hand cranked until the indented line going halfway across the dampener was in the sight hole ( was closest to this half line both times), rotor button both times was pointing at the positive post on the coil. I realize that just being in that sight hole isnt perfect tdc but im wondering if it hasnt jumped a tooth on the chain? Also for the first time since its been dead I can hear air exiting the exhaust when cranking, and no longer hear the metal-ish noise (what i had assumed to be either starter tooth/ flywheel noise or timing chain noise). Maybe its just a weird coincidence or something but I found it kind of odd lol
 
Ps since the truck quit plug wire spark has always been more orange that blue despite improving coil spark
 
BigBlockMopar28 said:
So i confirmed compression stroke on #1,
Click to expand...

I explained how to check this from end to end. There is no need to guess. So far as the cam slipping, go to MyMopar and download a couple of factory service manuals. There's a procedure in there to check the cam timing. You can "estimate" cam timing if you have some idea of what the cam "is". You can also wrench the crank back and forth CW/ CCW and watch for rotor movement, then measure how far the crank moved. A "really sloppy" chain might be 5 degrees or so. If it's less than that, then the cam did not slip.

Summary:

1....Check timing marks accuracy with a piston stop
2.....Bring engine to TDC on compression then adjust for desired timing advance BTDC
3.....If you are a purist, check alignment of distributor gear, not necessary really
4.....Drop the distributor in, rotor pointing to driver side
5.....Retard dist, then advance watching for reluctor/ pickup alignment. If vacuum can ends up in a bad spot, move intermediate gear a tooth.
6.....Determine which cap tower rotor is approaching and drop the no1 wire into that plug tower
7.....Install remainder of wires and START THE ENGINE
 
BigBlockMopar28 said:
Ps since the truck quit plug wire spark has always been more orange that blue despite improving coil spark
Click to expand...

Check spark with a WIRE coil wire and test gap, NOT a resistor wire. Should get a nice hot "snap" at least 3/8 and more typically 1/2" long

CAVEAT!!..........If you are checking spark by jumpering the starter relay and not using the key, you are going through the ballast and not getting the higher coil voltage from the ignition switch--bypass circuit. You should get a stronger spark WHEN USING THE KEY to crank
 
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