1968 continental engine timing / fuel mix adjustment

[Cole1968]

I have a 1968 continental with the 460, Im having trouble figuring out how to properly set the carburetor mixture adjustments and timing.I marked 10 degrees BTDC on the crank pulley and tried to retard/ advance the timing with my timing light but I can't see the marks no matter how far I retard or advance the distributor. Before trying to set the timing I did adjust the idle mixture screws and idle according to the shop manual but I am not sure if it's correct The carb is a carter 4300 4barrel.

If anyone has advice it would be appreciated Thanks-cole

[Dan Szwarc]

It's possible your harmonic balancer has shifted. To verify this, you have to set the crank to TDC using the air or valve method, then visually verify the marks.

You'll have to google both methods, but the AIR method is basically putting a whistle on the spark plug of #1 and turning the crank until it stops. The valve method is pulling the valve cover and visually verifying both valves are closed (but it's not as accurate). The best combines both. Then you inspect to see where the timing marks align with the pointer.

Find the thread, "Throw away your timing light" to learn how to tune the carb idle screws using the vacuum gage.

[frasern]

If you try it in a very dark area (inside a dark garage), the light will travel farther around the pully. Also you could use different coloured crayons in 4 or 5 places around the balancer and see if one is close. That will verify if it has moved.

[Cole1968]

Thank guys, I will try this next time I work on the car

[TonyC]

Cole, here's the link to that thread for you, so you don't need to waste much time just trying to find it: https://www.thelincolnforum.net/phpbb3/ ... ming+light

I'm thinking about re-studying that thread in detail myself. I dismissed it where setting timing was concerned because, although the original criticism of the engine's damper and timing marks was a valid point, it's moot to me because I've cured that design flaw, so I can use a timing light on my engine for ignition purposes without any doubt at all of its accuracy. However, if the thread has guidance on how to fine-tune a carburetor to its best economical settings via reading a vacuum gauge, I could use that guidance.

---Tony

[ravnlinc]

If you engine is running, you are 90% there with timing. You can't bee too far off. If you have an adjustable timing light, it should be set to 0 degrees. You say you have the damper marked at 10 degrees TDC. Have the timing light trigger sensor on the number 1 cylinder which is the passenger front. Pop the distributor cap off and rotate the engine til the central rotor aligns to where the number 1 spark plug wire is on the cap. That should be very close to TDC. Check your mark on the damper with the needle bolted to the block. It should read pretty close to (+/- 15 degrees) to TDC. If not your damper has shifted a lot an not reliable. You can remove spark plug 1 and put a screw driver in the bore to check the piston height. Rotate the engine back and forth to the point midway between stops rising and starts falling. That is your true TDC. Again check your marks on the damper and the needle. From there you should make any timing corrections to what you see on the timing light and what it really is to then rotate the distributer (with engine running) to get your base 10 BTDC.

Hope that helps.

Joe

[Cole1968]

Thank you guys again for the feedback, I ordered a new timing light that isn't junk and has a built in tachometer.So next time I run it I should be able to figure it out. I must be pretty close with all the adjustments already because I'm pulling just over 20" of mercury for vacuum off the manifold

[papawayne]

Sounds like you've got it. Even 18" is good. Wayne

[Cole1968]

So Im back again with a realated issue, Even though the carb idle mixture Is tuned right to the best of my knowledge It still smells rich and is a bit smokey.Not sure what the problem is. Its a bit hard to start too

[TonyC]

Had similar problems myself, early on after the rebuild. It could be that your mixture is still too rich and needs more adjustment, like a quarter-turn inward for each mixture screw...that is, if you're permitted to adjust more. I remember those particular carburetors were fitted with limiting doo-dads on the mixture screws to prevent any over-aggressive tuning, part of the first round of pollution-control demands of the government. But if you can, I'd say turn the mixture screws inward about a quarter-turn, then assess the smoke/soot response.

If it's hard to start, the choke may not be operating like it should (which could also contribute to over-enriching the fuel mixture), or the cold-idle adjustment is off. I had to make tweaks to both those settings, along with the mixture screws (Carter AFBs don't have anything to limit the adjustments). I can't give guidance on that particular model carburetor, but the shop manual should, if you have the OE carburetor still installed. Of course, if you swap it for something aftermarket, then the shop manual becomes irrelevant for adjustments.

---Tony

[Cole1968]

Ill give that a shot, Ive been manually operating the choke because the plastic cam lobe is busted off.I need to find a new one but cant locate one