Trying to tune my 4.5 otherwise know as an excerize in "TOOLS"

[Litton]

So far, this has been an interesting experience. Finally found the little pointer hidded under the upper hose, finally found the time marks under the dirt and put a dab of paint on the -5, +5, and +10 marks. Still can not get the dwell to 30 but hopefully my new Pertronix stuff will come in soon and that will be come a mute point.

I have no idea what the timing is set at as the little white dabs I put on are no where in sight. Now I have to go buy a "tool" to get the distributer screw loose. That bloody thing is buried way the hell down there.

Let's see, the dwell is at 6, the timing is to hell and gone.....why does it even run???

Question, my idle is at 600 with the engine warm and the vac. line connected. When I pull the vac line the idle goes to about 1000. Is this OK for setting the timing.....still no marks but after I buy ANOTHER "tool" I should be able to find them.

I'm not sure if I run to the store more often for "things" or "tools".

[Tomguy]

I use 1/4" drive with extension, and a 5/16" or 8mm socket. Oh, and a flashlight to see the damn thing

Are the white marks visible if you yank the vac? If so, your timing is very late. Otherwise, no idea. But no, setting by idle speed isn't really posible - the idle speed screw is used to set idle speed. If your engine is running at 600 and it's timed too advanced, setting it later might make it stall. It's not that you can adjust timing by the idle because you can change the idle (or a mechanic or PO could have changed it... you get the idea).

[MikeTangas]

Verify that you inded have the timing light attached to the #1 wire, any other and the light will flash at the wrong moment.

Plus, as I recall on the 4.5 it takes a really awkward angle of attack to get the light aimed at the pointer. I remember the fan clipping my light as I got it just about right.

[Tomguy]

Mike: That's what bungee cables are for! I used one to tie my radiator hose back. It makes it a lot less akward of an angle to view it!

[Litton]

I'm reasonably certain that I am on #1. I am on the first cylinder on the passagers side. Then, if you are standing at the front of the car looking at the distributer the wire for # 1 is at the 1:00 positon.

The bolt holding the distrubuter is an allen head and it looks like the distruter is rotated all the way clockwise. I wonder if I have a a couple of wires swapped?

When the idle speed jumps with the vac off it makes me thing the it has a vacuum retard. or is it just leaning out because of a vac leak. If so, should on plug the vac line after diisconnecting it?

What should the idle speed be with the vac connected. Also, at what speed does the centrifical advance start to work.


Gee, this is fun.

[ctaylor738]

The way I understand vacuum advance to work is that higher engine vacuum holds the timing retarded. Then when you accelerate and vacuum drops, the timing advances. So if you pull the hose off, you are allowing full advance since the vacuum applied goes to zero.

[Tomguy]

Let me clear up the vac issue...
The vacuum is applied at all times unless the engine is above 212F (granted that your thermo-switch works) and/or the AC is on. I don't know if it comes off in 3rd gear but believe it does.
At all other times, full vac is applied.

The vac is a retard. Timing should be 5deg ATDC WITH it connected - about 7BTDC without, but mine (I think) only goes to about TDC or so I believe.

Advance is mechanical - rather simple system with springs, balances, etc. The best way to test it is to try rotating the rotor clockwise. If it goes without too much difficulty and, when released, springs back; you're good there.
You will KNOW it's advancing too much if, once you get timing set and can see the lines/dots, if someone SLOWLY increases the throttle, you can see rapid advancement and before 1500RPM, full-advance is on - this WILL cause BAD hesitation, mis(or back)firing, and so forth, when accelerating from a stop until about 2K RPMs. If advance isn't working, you won't really notice much other than possible smoke and/or hot exhaust manifold temps during a high-sustained RPM run (about 80MPH cruising on the highway for 10-15 mins).

To ensure that cyl #1 is where you're putting the wire, when you pull the cap off the distributor, at about 1:00 or so you should see a "notch" along the rim of the distributor metal (just a small line). It lines up perfectly with your #1 plug on the cap (and, if not, either the cap is wrong or the wires are on it wrong).

My distributor as well was as far to the right (retard) as possible, but I set it a bit more agressively - 3deg or so (which hurt me I think - I had to put 92 instead of 93 and I think I noticed some pinging).

Are you looking at the right spot to test the timing, and are you 100% sure you dotted the right spot(s)? A simple way of testing: There is a small plastic "box" on the passenger's fender below the washer resivoir, behind the EFI unit. The #3 wire will rotate the engine. With the TRANNY IN PARK and cap OFF, connect the (+) battery terminal to this with a jumper cable and rotate the engine until the rotor aligns with the notch. Your dots should be close to the pointer (definetly within view).

The pointer is a little difficult to see. At first (before removing my rad, before I was really working on the car) I always thought you looked in the little hole in the water pump The pointer itself is below the distributor and below the water pump, in fact.

Be AWARE that messing with the distributor points WILL change timing. It's almost impossible to reset them EXACTLY the same every time! Also, I've been having issues measuring dwell myself. If I hook my meter to my coil it ALWAYS says 25, if I hook it to before the resistors it ranges from 40-35. It's a little confusing to me so I just usually "guess" it and then set my timing I think my resistor(s) are bad (or going) though because *cough* erm... when the 2nd ignition box blew, I noticed the points had been fully closed and the ignition in "run" with the car off - the resistor smoked and got hot, but it didn't blow (the box went first ) Thank god the new one was all of $5.

In retrospect, it's good it DID blow. It sat for 5 years and got a rest until I could work on it myself - otherwise it would have undoubtedly been trashed, my parents couldnt afford parts anymore! *hugs eBay and Harry's U-Pull-It*

[Litton]

Tomguy, now that was a lucid explantation. I was beginning to think that the vacuum advance was really a retard. I will check that rotor/housing alignment immediatly.

In painting the marks, I was a little confused at first but the "0" mark showed up nicely as well as the -5 and + 5 on either side so I think I'm OK there.

I have about given up on dwell and will just hold the point gap to .3 mm (~.014") and go from there. My Pertonix stuff will be here tomorrow and that problem will simply vanish.

I was a bit concerned that checking the timing after the vac was disconnected that the higher idle would give a false reading due to the centrifical advance kicking in but in reading what you said.....the +7 must take that into account.

Great way to spend a lovely morning.....tinkering.

[Litton]

I think I might be making some progress. Per Tomguy, I checked the timing marks with the rotor aimed at the little notch on the housing. Seems I am about -12 from the O point. So with the vacuum that should put me at -17 and about -7 with vac attached, which would explain why no marks were in sight with the timing light but it would still run. Still need a "TOOL" to get at that allen head for the dist. Natually nothing is open today so I reckon I'll start on the rear brake till I have to do the Turkey thing.

I also noted that the centrifical stuff seems to almost work. Turn the shaft and it almost snaps back but I have to give it a nudge to get it to go all the way.

Why is my list getting longer the more that I do?

[Tomguy]

Litton: That's the way my mechanical advance works too and I'me fine with it. When the car is running, resistance in the points will help it return fully to the retard position.

The vac line is a retard line! With it connected, ignition is set later (if you look at how it works, the plate on which the points sit rotate in view of the rotor and shaft). With the vacuum cut, it advances for higher idle, better cooling and better performance.

You sound like your timing is VERY late. Try setting the points the way I do: at halfway to the rise on the octagon (halfway between center and the end of the 1 edge of the octagon) the points should be closed. After this point they should begin opening. In other words, the points should be on one of the 2 red points shown in the picture. Remember, changing the points changes the timing. Check after setting it this way.

[Litton]

That's pretty much the same way I do it. Are you setting the gap to .3mm?

[Tomguy]

No. I just adjust it so it's completely closed at one of those positions - and any further and they (begin to) open. I COULD measure my gap I suppose... but I'd have to be careful to get the measurement exactly on the apex and I would have to make sure my feeler gauges are 100% free of oil!

[Litton]

I never thought about seting the points to just close but as I think about that it certainly makes some sense. Really, it would be no differant then setting the gap as height of the lobe determines how far they open.

First, I think I will reset the destributer to that the TDC (0 mark) and the rotor/housing notch are all aligned. That should get rid of my -15 problem. Then, if it starts, will regap the points for closed instead of open.

Maybe my Pertonix stuff will show up today but first I have to go find a "tool" to loosen the dist allen bolt.

[Litton]

Still working on this problem. Tryed setting the points to closed vs. open ended up with a gap of about .45mm but my dwell seems unaffected by gap....still at ~5 or 6. Timing is about perfect now. Idle seems a little high at about 800 with vac on but seems happy. What is really interesting is that the point gap doesn't seem to mean a thing.....granted it affects the timing but for running and dwell......doesn't seem to do squat. I suspect it's me.

Oh yeh, you know you're getting old when you have to put reading glasses on to work on a car.

[Tomguy]

Litton: How new is your dwell meter? It really sounds like it just isn't working. Your readings definetly should have changed (a lot)!