Thread: newb timing question/issue

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You're 180* out and stay away from anything that says Accell

When you put the dizzy back,before hand did you line up the oil pump drive slot with a flashlight and a long screwdriver so the slot was facing front to back??.You said you had some doubts about the H/B and it's timing marks.Now might be a good time to check that.Pull the valve cover for number one cylinder.Watch the exhaust rocker open and close,the intake valve open and close,and then the piston on number one at TDC.The piston at TDC should be showing 0 on the H/B.

No luck. First tried turning the dist 180. Nothin. Then Cranked the engine by hand to tdc. Pulled no.1 plug to make sure(stuck a pen inside and felt the piston) turned the oil drive key so that when I set the dist in the rotor pointed at no.1 on the cap, where it should be. Again, nothing. I am replacing my plug wires correctly. I've checked over and over to be sure. I havnt a clue as what to do next. As for the oil key, why should it be positioned with the groove front to back? I tried it and when I set my dist in it it wouldn't point to no.1 on the cap. I don't see how the oiler key position would change things. I know that's what keep it from dropping in a setting correctly, but does position matter as long as I'm getting the rotor to point where I want it to? I'm baffled.

That is the way we set them at the Chevy engine plant when during testing them we found them to be off.You can get the dizzy to drop,but it would be one or two teeth off.Is the H/B on 0 when 1 is at TDC??.It has to be there to get the teeth on the cam to line up with the dizzy and line up with the oil pump drive.You need the proper timing position to advance or retard the dizzy correctly.

With the dist where its at, no.1 at tdc, and zero on the mark, the rotor is pointing at no.1 on the cap. So, mechanically, is this all correct? How it should be? Perhaps its electronic failure now. How often do these factory modules wear out? It said singapore on the backside, so I was skeptical putting it back in, but before I pulled the dist, the truck ran. All I did with the module when I pulled it down was wipe it off with a rag and plug it back in. I put the dielectric grease on the backside. I did put the dist back together correctly. No missing parts. All in the same order and position it came apart. So I know that the moving parts are good.

I mean the dist parts are correct. Please tell me if the tdc and rotor are all set how they should be.

So can anyone tell me if I'm setting it up correctly from a mechanical standpoint. No.1 at tdc, compression stroke. Dist rotor turned to face no.1 on the dist cap. Is this all correct? I havnt been under the hood for a couple days, been busy, but I do need confirmation. Thanks again.

You can't put di electric grease under a module

Put the crank pulley at about 20* btc and turn the dist til the rib on the rotor (reluctor)lines up exactly in the middle of the center of the module windings(where the metal sticks thru
you should be able to check for spark just by turning the ignition on and off causing a spark

Originally Posted by stavi

So can anyone tell me if I'm setting it up correctly from a mechanical standpoint. No.1 at tdc, compression stroke. Dist rotor turned to face no.1 on the dist cap. Is this all correct? I havnt been under the hood for a couple days, been busy, but I do need confirmation. Thanks again.

Aaaaa-did you read what I suggested????.That sir is not a guess.

Sorry,listen closely.That is the door on here slamming behind me as I leave this thread.My work here is done.

Hmm – don’t know why you used dielectric grease under the module. Dielectric grease is high content silicone and works well to keep moisture out without being electrically connective. As mentioned above, use it on the rotating-weight assembly. Not a good for the underside of your module where it meets the heat sink. Should use a heat sink paste there.

Okay - let's fix this thing once and for all. Go back and read this entire post - pay special attention to Gary and Jerry then there are two things YOU MUST DO. 1) Enlist a friend (to be used a little bit later, I’ll tell you when) and 2) Purchase a six pack of your favorite beverage (again – I’ll tell you when you need this!!


As to your timing issue, you need to be absolutely certain that #1 is at top dead center (TDC). There is, or should be, a TDC or zero mark on your balancer. You’ve indicated that there may be a problem with your balancer so this might be a good time to procure a new, known good harmonic balancer. There will be other degree marks however; the TDC mark will usually be the last mark to come to the pointer on a stock balancer when the engine is rotated. It is almost always the predominate mark in term of length and will have a “0” (zero) next to it

This mark on the balancer indicates TDC of the piston in the #1 cylinder. This may or may not be on the firing stroke as the cam rotates at half crank speed, it is possible for the ignition to be 180 degrees out of phase with the crank. As such, the cam is aligned on the firing stroke of the crank only every other revolution.

There are several ways to positively guarantee the crank-to-cam phasing. If you can easily get to the #1 sparkplug, remove it and cover the hole with your finger and enlist the services of a friend to rotate the engine. As the engine approaches TDC, both valves close and compression will blow your finger away from the hole. As this happens, check the balancer. You should be close enough to TDC to see the mark. This might take several tries to get the feel for the compression but believe me, you’ll know. Once you’ve felt the compression. Rotate the engine back to the zero mark.

Now the No. 1 piston is at TDC with the cam aligned to be on the firing stroke. If the distributor were to be installed here, the spark would be retarded. Rotate the engine about 15 degrees in the direction it runs (clockwise looking at front). Rule of thumb - on a small-block Chevy, approximately 1/16 inch on the surface of the balancer (any size) is real close to 1 degree. This is not exact, but it will be close enough to start the engine. Timing tapes are available from your local parts store (or Summit) that allows you to fully degree a stock balancer.

Drop in the distributor when the crank is positioned at about 15 degrees. Remember to turn the oil pump drive so the distributor tang engages it as the distributor gear meshes with the cam gear. If done right, the rotor will point to the No. 1 terminal on the cap. This may take some time, and a bit more effort than you thought, but now the distributor will be correct and ignition timing close enough to start and adjust. When the engine fires up, adjust your timing and go for a test drive. Okay – now sit down (with the friend you’ve enlisted) and have cold one or two – depending on the thirst level. I sometimes need three – but only if I’m not going to drive anywhere for several hours!

Trust me – I’ve worked on a lot of SBC and I still need to think this through each time I remove and replace a distributor. Take your time, don’t get frustrated as we’ve all been here – you will get this!

Good Luck,
Glenn