[Bill Hanlon]

A question and a request.

Where is the vacuum advance unit?

Could you take and post another picture that shows all 6 spark plugs, all the plug wires and the distributor cap at the same time?

[Carousel-Red]

By chance, do you have a 69 cam gear that requires the timing mark to be at the 6 o'clock position?

[66sprint6]

I'll have to get the pics tomorrow. The vacuum advance does face rearward. I googled a few images of a '67 engine and found this to be the standard. The diagram posted by Carousel-Red could be helpful. I definitely do not have the rotor 7 degrees clockwise from cylinder #1. I'm fairly sure that it doesn't have the '69 cam mark location, but you never know. I'll keep you posted.

[Carousel-Red]

The "Rotor CenterLine", from the 69 Manual, may be misleading. I think the rotor is supposed to be at the "CenterLine No 1" position 7 degrees CCW. The "Rotor CenterLine" may actually mean Distributor CenterLine where the coil wire enters. Reference the photo below from the 68 Manual.

[TheSilverBuick]

It definitely should be slightly past the #1 post centerline (aka ~7º).

Worse case, go to baseline. Pull the number 1 spark plug (or all), stick a piece paper towel in the #1 hole or feel/listen carefully, and rotate the engine until it's blowing out the spark plug hole (compression), when it does that, continue turning the engine until the crank balancer mark is pointing at the +5 mark on the timing cover. Then rotate the distributor base until the rotor is pointing straight at (or error slightly past) a distributor post centerline, make that #1, and set your spark plug wires accordingly. Fire the engine up, re-check your ignition timing and fine tune it if needed.

If you want the #1 post to be in a certain spot, after you have the balancer pointing to the timing mark on the compression stroke, you may have to pull the distributor and re-clock where the rotor is pointing, which will likely require using a screw driver to rotate the oil pump shaft clockwise slightly as well to re-seat the distributor. This method, you can set #1 post to about any location by just getting the rotor to point to that spot when you set the distributor back in.

[66sprint6]

I've included a pic of the overall Dizzy/vacuum advance and wires. I must have checked the firing order a dozen times. But I'm wondering if all of this cranking it over and not firing has flooded the heck out of the engine. I looked down into the #1 spark plug hole and it seemed to be full of carbonized crud. It wasn't like that before. I gently stuck a screwdriver in there and it came out with a bunch of some kind of residue. See the second pic. I'm sure that the distributor and everything are all lined up properly. I'm not sure what to do next, but I took all of the plugs out and the carb off to hopefully dry everything out. I didn't want to put my newly rebuilt carb on until it was running again, but maybe I should.
I appreciate everyone's help. I am determined to get this thing going again. Although the engine was not running and I couldn't get it to operating temperature, I did a compression check and found all cylinders to be good and even at around 150/cylinder. That made me feel better. I am going to leave it alone for a bit, as my frustration level is pretty high right now.

[TheSilverBuick]

Heck, mine only tests to ~135psi. I'm at high elevation though.

Firing order on the cap looks good. Just depends where the rotor is pointing. The gunk on the screw driver would be expected for any engine that doesn't get hot and loaded up regularly. The fuel makes the gunk soft. At this stage, it wouldn't concern me at all. One you've driven it at operating temperature a few times, preferably with a few spirited starts, then check it.

[Bill Hanlon]

Do you have a timing light?

If you do, I'd leave the plugs out, hook up the timing light, remove the hose from the vacuum advance, have someone else turn the key to start and quickly verify ignition timing.
.... If it is anywhere between a few degrees retarded and 15 degrees advanced, it should be close enough to start and your problem is elsewhere.
.... If it is NOT anywhere between a few degrees retarded and 15 degrees advanced, you are probably a tooth or more off on the distributor gear.



Question: Does anyone know how many teeth are on the distributor gear?

[LAROKE]

Originally Posted by Bill Hanlon

Boy am I embarrassed! I haven't touched a Pontiac 6 in many moons, but assumed (there's that word again) that it turned the same direction as a Chevy 6 from the late 60s. I just spent a bunch of time working on one of those that belongs to my across-the-street neighbor.

Oh well, ignore all I said in this post because it is backwards.

I get clockwise and counter-clockwise mixed up all the time, Bill.

[Jeff Hamlin]

18-Teeth Dist Gear.


I will say you are correct about the '67 SM it is a contradiction of it's self showing the Vac adv; facing both ways in the manual??
But this should not cause issue, as it can be orientated either way and still allow one to shoot for #1... I pulled one out of the bin and loosely set it at timing mark both ways.


TDC has to be clearly determined. As mentioned it appears your a few teeth off/out?

...

[66sprint6]

Well,
I've checked and rechecked and I've never been at such a loss. I used my timing light with the plugs out like Bill suggested and it was between 5 degrees advanced and zero. I didn't want to fiddle with it beyond that so I left it there. It's got compression, fuel and spark as far as I can tell. Maybe it's a little beyond my abilities or I've done something to the engine that I don't know about. So disappointing. It was running before but not great. Now, it doesn't even try to catch. It does backfire here and there so I'm wondering if that's a symptom of something. I even tried stating fluid, I was so desperate. I'll have to find an OHC6 guru here in Toronto that can hopefully help. But please keep the suggestions coming. I haven't totally given up hope. It's likely one stupid thing that I've done or not done that's keeping this thing from running.
Thanks everyone for your input this far. You guys are great.

[Bill Hanlon]

You have compression, and fire at about the right time in cylinder #1. The plug wires look to be hooked up properly, so I assume the other five are firing correctly too. It is easy to tell about #6 by just moving the timing light pickup to #6. It is exactly one crankshaft turn from #1, so it should also read 5 degrees BTDC.

That mostly leaves fuel.

It is possible that spark is jumping from one wire to another, but that is hard to see on a non-running engine. Check the distributor cap on the inside for carbon-tracking from one terminal to another.

One thing we didn't consider is that the outer ring of the harmonic balancer has slipped on the inner hub, making the timing mark in the wrong place. You can verify the mark on the balancer with a piston stop. I just did this on my buddy Charlie's Chevy II 6. We tried to use a commercial piston stop, but it wouldn't reach far enough to touch the piston. The Chevy 6 uses VERY long reach plugs. We made our own piston stop out of an old spark plug, a threaded all the way 3/8" x 3" long bolt and a nut. Busted all the insides and ceramic out of the plug, then tapped the remaining metal part of the plug for the bolt. Used the nut to lock the bolt in place.

[Jeff Hamlin]

There are timing/alignment marks to check if the HB has slipped any;

[66sprint6]

A local mechanic told me that I won't get it going without dumping a couple tablespoons of oil down each spark plug hole after the flooding the cylinders. Unfortunately, they don't sell Marvel mystery oil here anymore. So maybe straight 10W?

[TheSilverBuick]

He's probably concerned about the cylinder walls being washed with gas and dry. ATF is a better solution than motor oil, IF you actually want to do that. If you pull the dipstick and it doesn't smell like gas, I personally wouldn't worry about it. If it smells like gas you need to change the oil and probably prudent to give each cylinder a few shots of ATF, though it's effectiveness IMO is questionable.

I would probably pull the spark plugs, give the electrode and ground strap a slight swipe each with fine sand paper, blow the dust off and put them back in. Ensure your gap is around .035" or slightly less.

Cranking the engine with the plugs out also accelerates clearing a flooded condition, bonus points having the pedal at WOT to minimize vacuum/air speed pulling fuel through the jets/venturi's.

[66sprint6]

Well. still no joy. I'm trying to figure out if a sputter/backfire has something to do with it being out of adjustment. When I crank it, it comes around like clockwork. I think I'm going to have to bite the bullet and take it to an old school mechanic that operates here in Toronto. I'm hoping that with some proper diagnostic equipment he can find out what the issue is. Wish me luck.

[66sprint6]

My mechanic said that the distributor was 180 degrees out. I don't know how that is possible. To me, that means that the rotor would be pointing at the number 6 post on the cap. But I took the cap off after getting it home and it looks just like I had it.
Anyway, it purrs like a kitten. It cost me a couple hundred bucks, but what the heck. It was also a relief to have the guy tell me that the engine is like new.

[Bill Hanlon]

Distributor 180 out still shows timing right because 180 distributor degrees = 360 crankshaft degrees, with #6 cylinder firing at the same 5 degrees before top center that #1 does, just one full revolution later. But my(and others) suggestion of detecting the compression stroke on #1 cylinder should have detected the 180 out condition. I guess we just didn't emphasize that test enough.

[66sprint6]

You did emphasize it, Bill. But I didn't follow through properly. I just wasn't patient enough. But I sure learned something there.
Thanks again for your expert advice. Hopefully I can pass on the experience to the next guy that may have the same problem.

[TheSilverBuick]

Common problem, but certainly glad it's running good and nothing like having a lesson learned!