1986 460 Smog Pump Delete

[ArdWrknTrk]

After my last post, it wouldn't start. Thankfully, I didn't waste hours before I realized it could be out of gas, and sure enough, it was! Lol

So after I went and got 2 gal of super premium (93), and made a couple of store runs, I started testing timing, bit by bit. It read the same as last time to start, aprox 22 degrees.

First, per the factory instructions on the radiator support, once up to temp I pulled the dist vac adv and plugged it. This made it run rough, and the timing dropped to a wobbly 12-15 degrees, and vac dropped as well:

From there, the only adjustments I made were to the dist vac advance, which I learned is fully open (counterclockwise, if I don't have that backwards) at 10 full turns. I made 2 full turns at a time, all the way up to 10, and then all the way back down again. The results below were the same on the way up as they were on the way back down.

Dist Vac Adv positions/readings (all turns counterclockwise):

1) Closed (turned full clockwise) = 22 deg and vac 21-22 in.

2) 2 full turns = no noticeable change.

3) 4 full turns = timing dropped to a wobbly 14-16 deg, vac 19-20in.

4) 6 full turns = timing dropped to a wobbly 13-15 deg, vac 17-18in.

5) 8 full turns = timing dropped to a steady 12/13ish deg, vac went back up to approx 20-21in.

6) 10 full turns = timing MIGHT have dropped a smidge, still 12ish deg and steady, vac MIGHT have gone up slightly, but not sure since the vac was a little jumpy at every point by about 0.5-1in. Here's timing/vac at 10 full turns:

Questions:

1) Is the engine supposed to run rough when I disconnect the vac adv?

2) Yhe timing instructions say "800 rpm max" but I doubt it's at 500 with the vac adv hose off, am I supposed to have someone give it throttle up to 800 to see the timing at that point?

3) I want to take it around the block and see how it does. Which of the above dist adv settings looks like the best to set it at for that test drive?

Lastly, these pups are some of the best around, Jim. We fostered this guy back in March after he was found after being left in a house for over a month by tenants that got evicted, he nearly starved to death. We knew from the first day he was never leaving us. Here's him when they found him, and now, doing what he loves the most - keeping me company while he waits for a chance to sit in the truck lol

Thanks again for all the help!

He looks so happy that he's getting some love and attention!

My dog was a pup born to a very pregnant dog that got caught up in a police raid.

Because I knew those guys, I got a 5am call to "come get this bitch, because the pound will put her down"

Momma was very sweet and I took my pick of six. (To be honest, she picked me! We bonded right away )

Yeah, you shouldn't be using the vacuum can to adjust static timing.

Back the can off, turn the distributor itself to set base timing. (I like about 12°)

THEN set curb idle speed with the throttle stop, 750 is ok,

Play with the mixture screws looking for highest vacuum.

Adjust curb idle, twiddle the mixture screws, back & forth until you see best vacuum.

Then I like to open them both 1/8-1/4 turn just so I'm not running too lean.

Then reconnect the vacuum can and reset curb idle to 750 (I like to be a bit lower myself)

Then, you can get to following those instructions from Crane, so you don't melt a piston.

[Bullnose Gator]

He looks so happy that he's getting some love and attention!

My dog was a pup born to a very pregnant dog that got caught up in a police raid.

Because I knew those guys, I got a 5am call to "come get this bitch, because the pound will put her down"

Momma was very sweet and I took my pick of six. (To be honest, she picked me! We bonded right away )

Yeah, you shouldn't be using the vacuum can to adjust static timing.

Back the can off, turn the distributor itself to set base timing. (I like about 12°)

THEN set curb idle speed with the throttle stop, 750 is ok,

Play with the mixture screws looking for highest vacuum.

Adjust curb idle, twiddle the mixture screws, back & forth until you see best vacuum.

Then I like to open them both 1/8-1/4 turn just so I'm not running too lean.

Then reconnect the vacuum can and reset curb idle to 750 (I like to be a bit lower myself)

Then, you can get to following those instructions from Crane, so you don't melt a piston.

Very helpful, Vivek, thanks. In that video he says an old engine that calls for 4-6 deg btdc is probably optimal at 14-16 deg. Is my 12-13 as an old engine not close enough?

Jim, what does "back the can off" mean?

[ArdWrknTrk]

Very helpful, Vivek, thanks. In that video he says an old engine that calls for 4-6 deg btdc is probably optimal at 14-16 deg. Is my 12-13 as an old engine not close enough?

Jim, what does "back the can off" mean?

Vacuum advance is meant to be additional to static and centrifugal advance.

It is NOT a means of achieving static timing.

[Bullnose Gator]

Vacuum advance is meant to be additional to static and centrifugal advance.

It is NOT a means of achieving static timing.

So "back the can off" means to disconnect the vac adv hose?

[ArdWrknTrk]

So "back the can off" means to disconnect the vac adv hose?

From what I can understand, you are using the can to adjust your timing.

It doesn't work that way....

You need to be turning the whole distributor to set the timing.

Then, I would suggest following the instructions as to how much vacuum advance you can get away with, given the gearing, tires, load, the fuel you use and your driving style.

They are a concise, succinct, step by step guide to optimizing your ignition timing.

There's really nothing for me to add.

[Bullnose Gator]

He looks so happy that he's getting some love and attention!

My dog was a pup born to a very pregnant dog that got caught up in a police raid.

Because I knew those guys, I got a 5am call to "come get this bitch, because the pound will put her down"

Momma was very sweet and I took my pick of six. (To be honest, she picked me! We bonded right away )

Yeah, you shouldn't be using the vacuum can to adjust static timing.

Back the can off, turn the distributor itself to set base timing. (I like about 12°)

THEN set curb idle speed with the throttle stop, 750 is ok,

Play with the mixture screws looking for highest vacuum.

Adjust curb idle, twiddle the mixture screws, back & forth until you see best vacuum.

Then I like to open them both 1/8-1/4 turn just so I'm not running too lean.

Then reconnect the vacuum can and reset curb idle to 750 (I like to be a bit lower myself)

Then, you can get to following those instructions from Crane, so you don't melt a piston.

Thanks. After setting the mixture screws to 2 full turns counterclockwise, here's where I'm at, with the distributor vac adv set to 8 full turns counterclockwise:

With the dist vac adv hose CONNECTED:

14-15 Deg.

With the dist vad adv DISCONNECTED and plugged:

-0 deg (same exact place TDC)

[viven44]

Thanks. After setting the mixture screws to 2 full turns counterclockwise, here's where I'm at, with the distributor vac adv set to 8 full turns counterclockwise:

With the dist vac adv hose CONNECTED:

14-15 Deg.

With the dist vad adv DISCONNECTED and plugged:

-0 deg (same exact place TDC)

With the dist vad adv DISCONNECTED and plugged:

You need to be at 8-10 BTC !

There is your problem

Turn the distributor clockwise (if I'm not mistaken its clockwise) until you are at 8-10 BTC

[viven44]

With the dist vad adv DISCONNECTED and plugged:

You need to be at 8-10 BTC !

There is your problem

Turn the distributor clockwise (if I'm not mistaken its clockwise) until you are at 8-10 BTC

This is a good video

You can see around the 6:00 mark where he is rotating the distributor while the engine is running (With vacuum advance disconnected) to set the initial timing... the nut at the base of the distributor needs to be loosened first and that is where the distributor wrench I recommended comes in handy. Sometimes a socket can get there at an angle.

That is a Chevy but the idea is the same.... the Ford distributor is in the front ...You will need to rotate it clockwise ...

[85lebaront2]

With the dist vad adv DISCONNECTED and plugged:

You need to be at 8-10 BTC !

There is your problem

Turn the distributor clockwise (if I'm not mistaken its clockwise) until you are at 8-10 BTC

Clockwise is advance on most Fords (distributor shaft turns counterclockwise) Nipple on the vacuum advance does not need to be capped when setting the timing, but Ford's advance scale on the balancer reads in both directions, from 10° ATDC to 30° BTDC or possibly more. Just be sure you are using the correct part of the scale.

[viven44]

Clockwise is advance on most Fords (distributor shaft turns counterclockwise) Nipple on the vacuum advance does not need to be capped when setting the timing, but Ford's advance scale on the balancer reads in both directions, from 10° ATDC to 30° BTDC or possibly more. Just be sure you are using the correct part of the scale.

Thanks for confirming. So Jeremy should be looking for ~10 BTDC, which is on the side of the scale with lines going all the way to 30 or 40 BTDC.