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WHoa! Vacuum advance is way off (I think)
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Author:  daveca5150 [ Sat Aug 25, 2007 9:17 pm ]
Post subject:  WHoa! Vacuum advance is way off (I think)
Cool, my car's charging system is good to go. Thanks for the help! ON to my next priority. I'm still trying to get this 63 valiant 225 timed correctly. It has the original distributor, and coil, new NGK plugs, cap, pertronix kit and plug wires. I bought a new timing light, my old one needed an adapter which I lost and I didn't trust my homemade adapter since the readings were so strange. This one seems to be giving me a good solid reading. I have previously driven around the neighborhood to try to find the best setting by how it runs. Now it is reading at about 40 degrees advance! This is with the vaccuum line disconnected. When I reconnect the vacuum, it jumps to 2 degrees retarded. That's roughly 42 degrees of movement and in the wrong direction, at idle! As you can tell, I pretty confused about what is going on. I have read and re-read the Stockel, Peterson and FSM manuals about timing. It all makes sense when I read it, but my situation defies logic. It shouldn't even run that far advanced should it? Why wouldn't there be a huge difference in idle quality when I plug and unplug the vacuum line to the distributor?
Author:  LUCKY13 [ Sat Aug 25, 2007 10:03 pm ]
Post subject: 
Sounds like you have more than one mark on your balancer. Mark the line you are using with white paint or something. You may also want to make sure that when the piston is at Top Dead Center that the line is on the Zero mark. You could have a balancer that has sliped a ring.


I am not sure what is going on when you hook up the vacume, but get the basics worked out & know where you are first.


Jess
Author:  daveca5150 [ Sat Aug 25, 2007 10:22 pm ]
Post subject: 
Thanks for the reply! Some history I should have shared. This is my first experience in automotive mechanics. I had the engine rebuilt by a machine shop, everything else was stock and original. It has never run correctly since the rebuild.

I marked the balancer myself. I triple checked it today with a piston stop and marked it with white out. I spray painted the balancer black before I marked it to make sure I wasn't looking at any other marks.

This is the procedure I used to find TDC -
Insert piston stop, rotate engine clockwise until piston hits stop, mark balancer, rotate counter clockwise until piston hits stop, mark balancer, TDC is right in the middle of two marks (about 10 degrees between marks).

I also confirmed this with the coat hanger method, so I'm pretty sure it's correct, but there's always a chance.

I just tried it at multiple positions between where it was and 2.5 degrees where the FSM says it should be. As I got it closer and closer to spec, there wasn't a huge difference in the idle quality until I hit 10 degrees BTDC. I kept going and it wouldn't keep running at all beyond 5 degrees BTDC. It's getting too loud for the neighbors, so I'll call it quits for tonight :(
Author:  SlantSixDan [ Sun Aug 26, 2007 9:06 am ]
Post subject: 
Remember, there are two TDC events per cycle. You need the TDC that is between the compression and power strokes. I wonder if you're maybe looking at the other TDC (between the exhaust and intake strokes). Also, you are using the frontmost cylinder, your spark plug wires are all hooked to the correct spark plugs and to the correct distributor cap terminals...right? THe engine can be made to run if the plug wires are in the correct sequence on the cap, even if they're not installed in the towers they're supposed to be, but it'll be very difficult to time the engine correctly!

Sounds like you are off to a good start on learning how to work on cars. You will definitely want to go get the three books mentioned in this thread ASAP.
Author:  daveca5150 [ Sun Aug 26, 2007 10:23 am ]
Post subject: 
Thanks Dan,

I have all three books and have tried to independantly figure this out unsuccesfully, which is why I'm here :)

#1 plug wire should be at about 4:00 on cap right? Where is 12:00? There are no marks on the cap so I'm not sure if it's looking at the distributor from passenger side of car like you would be while working on it. The mechanic friend that helped set it up initially told me it didn't matter which one was number one as long as the firing order was correct.
Author:  dakight [ Sun Aug 26, 2007 1:10 pm ]
Post subject: 
Quote:
Thanks Dan,

I have all three books and have tried to independantly figure this out unsuccesfully, which is why I'm here :)

#1 plug wire should be at about 4:00 on cap right? Where is 12:00? There are no marks on the cap so I'm not sure if it's looking at the distributor from passenger side of car like you would be while working on it. The mechanic friend that helped set it up initially told me it didn't matter which one was number one as long as the firing order was correct.
:shock: It certainly does matter! 12:00 is next to the block and 4:00 is pointing more or less at the oil filter. If I remeber correctly, the number one wire should be on the fender side of the spring clip that holds the cap on.
Author:  Bren67Cuda904 [ Sun Aug 26, 2007 1:28 pm ]
Post subject: 
Quote:
:shock: It certainly does matter!
Well... not really. Its best because everything just works out better. Like the plug wires being long enough for some and to short for others. But technicaly as long as the rotor is pointing to the same cap tower as connected to the #1 cyl on the compression stroke and all other wires are then connected in sequence based off the 1st cylinder, then it dosen't matter.
Author:  dakight [ Sun Aug 26, 2007 1:37 pm ]
Post subject: 
Yes, it's true that you can lift the distributor and reposition the rotor but why would you when it's just as easy to set it up right from the beginning? There are lot's of things you *can* do and make them work but that doesn't make them the right.
Author:  SlantSixDan [ Sun Aug 26, 2007 2:17 pm ]
Post subject: 
Quote:
#1 plug wire should be at about 4:00 on cap right?
Yep, and the clock position is determined by standing on the distributor side of the engine, looking down at the top of the distributor cap as though it were a clock face. 12:00 is closest to the engine, 6:00 is furthest away.
Quote:
The mechanic friend that helped set it up initially told me it didn't matter which one was number one as long as the firing order was correct.
True as far as making the engine run, but the plug wires only reach their intended plugs without extra problems when both ends are where they're meant to be...not to mention eliminating confusion as to which wire to hook the timing light to.
Author:  SlantSixDan [ Sun Aug 26, 2007 2:19 pm ]
Post subject: 
Quote:
4:00 is pointing more or less at the oil filter
No, 9:00 is pointing at the oil filter.
Author:  daveca5150 [ Sun Aug 26, 2007 2:24 pm ]
Post subject: 
Well, here is how I have it hooked up now. All of the wires seemed long enough. Number 4 was a bit too long, but that's about it. I know the numbers a hard to see, but the order clockwise is 1,5,3,6,2,4


Image
Author:  daveca5150 [ Sun Aug 26, 2007 2:39 pm ]
Post subject: 
Here is my timing mark at TDC compression stroke (both rocker arms are loose so both valves are closed). I used a piston stop and a degree wheel to find this mark, so I'm pretty confident about it.

Image

This is where my rotor is when the previous picture was taken.

Image


Where things are right now, my timing light is reading at 5 degrees BTDC and my engine was barely running
Author:  emsvitil [ Sun Aug 26, 2007 2:54 pm ]
Post subject: 
The usual position for #1 is where you have the #5.....
Author:  SlantSixDan [ Sun Aug 26, 2007 3:09 pm ]
Post subject: 
These are really good, helpful photographs. Your plug wires are installed one tower counterclockwise of where they should be. 5 is where 1 should be, 3 is where 5 should be, 6 is where 3 should be, 2 is where 6 should be, 4 is where 2 should be, and 1 is where 4 should be. Suggest you fix that, then remove and realign the distributor so the rotor points close to the (real) #1 location, then try setting the timing again. Some other questions: Are you sure the vibration damper and the timing indicator (on the timing cover) are from the same engine? If not, what are the years of the engines from which those two parts came?

I think you are probably closer than you realise to getting this figured out. This kind of timing issue can be completely counterintuitive and make you tear your hair out...until you get it right and everything works.

What condition is the distributor drive pinion in?

Note that Fram oil filters are kind of like cigarettes: One probably won't kill you, but if you use them habitually, sooner or later you may well come to regret it. :shock:
Author:  daveca5150 [ Sun Aug 26, 2007 9:46 pm ]
Post subject: 
That did it! I moved all of the wires one post clockwise and the timing mark showed up where it should be at idle. :D I'm not sure why that made so much difference, or why it was running decent and showing 40 degrees of advance with the wires configured one post counter-clockwise, but now everything seems to make sense. I get about 3 degrees of vacuum advance at idle, and I set it at 2.5 degrees BTDC with no vacuum connected. It has about 15 degrees at 2200 RPM, but I didn't feel like reving it any higher today. I test drove it and it definately runs better, but there is a miss under load. I'll try readjusting valves tomorrow.

Thanks sooooo much for all the help. I'll post some pics of the entire project soon.
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