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What position is #1 on your distributor?
https://slantsix.org/forum/viewtopic.php?t=57712
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Author:  mvh [ Mon May 18, 2015 10:17 am ]
Post subject:  What position is #1 on your distributor?

I am asking because I think my distributor is installed a few teeth off (1967 Barracuda 225/904). The car runs tolerably well at speed, but the idle is rough -- the distributor is retarded to the max and the timing at 1000rpm with the vacuum advance disconnected is way off the tab -- around 25 degrees advanced or more. I figure I can pull the distributor and try to reset it based on the TDC mark, but I thought I'd ask where the #1 terminal was supposed to be aligned. On this distributor it is around 4 o'clock, but it clearly needs to be significantly retarded. I'm guessing it would be closer to 5? :?:

Author:  Exner Geek [ Mon May 18, 2015 10:52 am ]
Post subject: 

Look at where the #1 spark plug wire is connected. It is usually over the vacuum advance or about 5 o'clock on mine, rotate the engine until the rotor is pointing to that area and the timing mark is about 30 degrees advanced. Then twist the rotor to fully advance the distributor, you want the points to be opening or the reluctor lining up with the electronic pick up at this point. If it is way off you may need to move the plate that controls how far you can move the distributor or juggle the tooth engagement. Remember the engine rotates twice for the distributor to go around once so keep track to where the rotor was pointing before you take it out and don't turn the engine over without the distributor in.

Author:  Reed [ Mon May 18, 2015 11:48 am ]
Post subject: 

Convention puts the #1 plug tower at about 4 o'clock near the vacuum advance pod. However, location of the #1 plug wire on the distributor cap is functionally arbitrary so long as the wires are in the right firing order and the rotor points at the correct spark plug tower at the right time.

It sounds like you need more adjustment in your distributor. Thee is a second bolt on the bottom of the distributor that can be loosened to allow more adjustment in the base timing. You also can pull the distributor and move the distributor gear one tooth advanced or retarded from its current position.

Author:  mvh [ Mon May 18, 2015 12:21 pm ]
Post subject: 

Ah, I didn't realize you could adjust the base bracket. I am more familiar with V8s, where you can pretty much spin the distributor all you want. Yes, what I want is more travel in the CCW direction. If that doesn't do it, I will try moving it one gear tooth.

Yes, I know the position of the wires on the cap is arbitrary, in one sense, but based on the different lengths of wires, I figured there was intended to be an optimal or standard arrangement. The #1 wire is currently positioned near the vac advance, so I will have to make some other adjustment to get the travel needed.

Thanks for the help.
Quote:
Convention puts the #1 plug tower at about 4 o'clock near the vacuum advance pod. However, location of the #1 plug wire on the distributor cap is functionally arbitrary so long as the wires are in the right firing order and the rotor points at the correct spark plug tower at the right time.

It sounds like you need more adjustment in your distributor. Thee is a second bolt on the bottom of the distributor that can be loosened to allow more adjustment in the base timing. You also can pull the distributor and move the distributor gear one tooth advanced or retarded from its current position.

Author:  cpslntdchrg [ Mon May 18, 2015 12:33 pm ]
Post subject: 

Welcome to the forum. As Reed said, 1 should be near the vacuum advance pod, some info in the internet:

http://www.allpar.com/slant6.html
(schematic)

http://pills52.com/2014/2695487/
(Schematic with picture)

(Scroll the pages down to see them)

The damper outer ring can slip with time, moving the timing mark from were it should be. You need to check if TDC corresponds to were the mark is. Take the cover valve off (if you want to follow valve opening), the spark plugs, and rotate the engine by hand until the engine is at TDC and check the mark. I used a compcams TDC stop tool

http://www.autozone.com/test-scan-and-s ... 85871_0_0/

Wayyy too expensive, you can fabricate one with a old spark plug, You will need to replace the bolt in the tool with a longer one (I used a 4 inch long, don't remember if I used 2-2.5), the way the spark plug is in the head wont let the bolt that comes with the tool to touch the piston.

Another thought: the distributor gear has fat teeth, move one and it goes far (15+ degrees, IIRC...). I have used the second bolt Reed talks about for fine tuning, go easy with it too.

PD: Idle can be rough also if the valve lash is not properly set. 0.01 intake, 0.02 exhaust, with hot, running engine. (I prefer 0.012 and 0.022, It makes my (tired) slant run smoother).

Author:  mvh [ Mon May 18, 2015 1:19 pm ]
Post subject: 

Thanks for the links. I thought of the damper, but it seems to be in really good shape. I tried using a piston stop to check TDC, but it didn't seem to make contact at all -- as you pointed out, the bolt must have been too short. I had bought it to work on a small block V8.

15 degrees CCW would be about right, I think. It wouldn't surprise me if the gear was off a tooth -- the car is in good shape but has bounced around for a while without a lot of use. An easy mistake to make (I know someone had the distributor out because they installed a Pertronix unit), and one that could go uncorrected since it seemed to be running more or less. I was given to understand it had a carb problem (but actually, that seems fine -- the mixture was perfect, going by the plug color).
Quote:
Welcome to the forum. As Reed said, 1 should be near the vacuum advance pod, some info in the internet:

http://www.allpar.com/slant6.html
(schematic)

http://pills52.com/2014/2695487/
(Schematic with picture)

(Scroll the pages down to see them)

The damper outer ring can slip with time, moving the timing mark from were it should be. You need to check if TDC corresponds to were the mark is. Take the cover valve off (if you want to follow valve opening), the spark plugs, and rotate the engine by hand until the engine is at TDC and check the mark. I used a compcams TDC stop tool

http://www.autozone.com/test-scan-and-s ... 85871_0_0/

Wayyy too expensive, you can fabricate one with a old spark plug, You will need to replace the bolt in the tool with a longer one (I used a 4 inch long, don't remember if I used 2-2.5), the way the spark plug is in the head wont let the bolt that comes with the tool to touch the piston.

Another thought: the distributor gear has fat teeth, move one and it goes far (15+ degrees, IIRC...). I have used the second bolt Reed talks about for fine tuning, go easy with it too.

PD: Idle can be rough also if the valve lash is not properly set. 0.01 intake, 0.02 exhaust, with hot, running engine. (I prefer 0.012 and 0.022, It makes my (tired) slant run smoother).

Author:  '67 Dart 270 [ Mon May 18, 2015 3:42 pm ]
Post subject:  piston stop tool

Yes, I use the same piston stop TDC tool, and I have to crank the center bolt all the way in to get it to touch the piston. Don't be afraid, the threads on the center bolt end, so it won't let you drop it into the cylinder.

brian

Author:  '67 Dart 270 [ Mon May 18, 2015 3:45 pm ]
Post subject:  correction

I use the Summit one:

http://www.summitracing.com/parts/sum-900189/overview/

By the way, always check Summit first, they often have much better prices than local auto parts stores. And, if you have the time, save up your purchases and do it in one go, over $99 is free shipping and it's really fast, usually next day.

brian

Author:  cpslntdchrg [ Mon May 18, 2015 4:22 pm ]
Post subject: 

Brian,

I have a 69, original engine. The tool I bought did not worked for me, don't know why (maybe the tool I bought is shorter, your slant has higher compression, or something else). Yes, It wont fall if you screw it all the way (but is hard to screw it after installing inside the spark plug tube). But again, after going to Home Depot and buying a longer screw with the appropriate thread, everything went smoothly (of course, be careful with a too long screw, you don't want to nick the piston wall on the other side of the block. I set the engine at TDC and then installed it with a tall socket).

Author:  mvh [ Sun May 24, 2015 6:57 pm ]
Post subject:  Solved, after some effort

Yesterday, I tried pulling the distributor and very carefully retarding it one tooth. I did, but the timing light showed 5 degrees BTDC at 1000, with the distributor turned to max advance. So that was too retarded. Which makes sense, if you calculate 360 divided by 13 teeth = 27.7 degrees.

So I pulled it again and looked at that adjustment bolt on the bottom. It was adjusted all the way to the advance end, but there was a deep impression of the bolt at the other end, as if it had spent a long time in that position. So I moved that over and dropped it back into the original gear position. When I fired up the motor it immediately sounded smoother -- for about 30 seconds. Then there was a crunching noise and it shut down.

When I popped the distributor cap, one of the clamps went flying off, and I never did find it. Grrr. And when I pulled the distributor, I found out what went crunch -- it was the plastic drive gear. For a moment I thought I was dead in the water, then I recalled seeing a distributor in the big box o' parts that came with the car. Yep, a whole spare distributor. Yay.

But when I was trying to remove the broken distributor to my workbench, I realized it was hard-wired to the car. The hot lead to the Pertronix Ignitor ran all the way to the ballast resistor, where it was crimped with two other wires into a female spade connector. I decided that wasn't going to stop me, so I snipped the lead off at the crimp, Later I crimped on its own female end, and found a brass splitter (2 males and 1 female) to put on the ballast resistor, so it would be removable in future.

On the bench, I drove out the pins on both distributors, swapped on the good gear, swiped a clamp, and was ready to put it back on. BTW, the other distributor had its bracket adjusted exactly the way I had just set up the first one, so that seemed like a good sign.

By this time it was dark, but I had my trouble light, so I installed it and fired it up. This time the timing at 1000 rpm was 15 degrees advanced, and that was in the middle of the adjustment. I decided to declare victory and put my tools away. Now that the timing is within a reasonable range, I think I can turn the idle down, but I wanted to drive it first. Oh yeah, I did fish the broken half of the gear out of the motor.

Today, I took it on a nice drive to warm it up, then went through the carb idle set up procedure. Now it is idling at 550 and showing 7 or 8 BTDC, and seems a heckuva lot smoother.

Author:  cpslntdchrg [ Mon May 25, 2015 6:29 am ]
Post subject: 

Excellent! :D

Author:  Sam Powell [ Fri May 29, 2015 9:19 am ]
Post subject: 

Definitely a happy ending to that story. Glad you were able to get it sorted out. I tried to get mine started once when it was off one tooth, it it never would start. That is an easy mistake to make.

Sam

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