Hi
It is a 66 Mustang 289 with around 39k miles. The actual TDC is not on the 0 mark of the crank pulley anymore. It's approximately 10 degrees after. I'm trying to fine-tune it but if I advance the timing, the car runs fine but doesn't start when hot anymore. I have to redo the whole timing procedure. It happened to me on the parking lot two times already. If I retard it more, the car is a bit sluggish at low RPMs. What can I do?
The actual TDC is not on the 0 mark of the crank pulley anymore.
Is your vibration damper separating? If so better get that fixed before it comes apart completely.
You could always paint on new, corrected marks, start with factory specified timing, and fine-tune it from there. Either that or use a timing light that's adjustable and can compensate for the timing mark error.
Bear in mind that ignition timing at idle just sets the starting point. The overall timing curve is set by distributor vacuum and mechanical advance. If that's not correct the engine won't run right even with initial timing set correctly.
@chucktobias No, the damper is fine, despite of its old age. OK. How many degrees should I set? I find a lot of information online. Like Ford recommended 6 but some say that 10 or even 12 before TDC is best.
Start with the setting in the factory shop manual and adjust as needed. In most cases you'd advance timing a little at a time until you get detonation on acceleration and then back off.
Although I don't have a factory manual for that car I do have a very large 1965-1972 Chilton manual that covers all U.S. models during that period, and the information there is drawn from the manufacturers.
Tuneup specs for the 1966 Mustang with 289 calls for 6 degrees before top dead center EXCEPT for models equipped with a Thermactor. Those are set at TDC. The Thermactor was a California-only emissions device that injected air into the exhaust manifold. The TDC setting was for emission control as well rather than best engine efficiency so today I would ignore that in favor of the 49-state specification if you happen to have a Thermactor-equipped model.
I would therefore use the six degree BTDC setting as a starting point then, as I said, fine-tune the timing to whatever works best with the grade of today's gasoline you'll be using and the current state of your engine.
Be sure to disconnect and plug the vacuum advance when setting ignition timing, with the engine running at the specified idle speed to avoid interference from the distributor mechanical advance. That is listed as 600 RPM for manual transmission, 500 RPM for automatic. (The automatic trans spec would be in gear, though you obviously won't want to leave it in gear while working on the car. It probably equates to about 600 RPM in neutral.)
@chucktobias It currently is set at 6 degrees. The engine lacks of power. I use premium gas. Someone has drawn a line at 10 degrees. Should I increase it at 10 too?
Premium gas today is not what it was in 1966.
You can increase the timing a little at a time and test to make sure it does not ping on acceleration. I would do one or two degrees at a time until you find the sweet spot.
Bear in mind that if there is a problem in the distributor mechanical or vacuum advance the engine will lack power. Total advance varies with engine RPM (mechanical advance) and load (vacuum advance).
@chucktobias Oh I see now! It is a new distributor, when I received it, I sucked air out of it and it moved, and it rotates properly inside. The hose that goes from the carburetor into the distributor is a bit short and bends at the plug of the distributor! Will putting a longer hose fix it?
A longer hose will only make a difference if the short one is being choked off due to a sharp bend. To test the mechanical advance you need to disconnect the vacuum advance and compare the distributor total advance at different RPMs to factory specification.
@chucktobias Yes, the hose has a sharp bend
@chucktobias Where may I download a copy of the workshop manual?`RockAuto sells them but they are on a CD or USB stick.
That's the kind of thing you need to search around for. For example it looks like this place offers it in eBook format for $16.95:
https://fordmanuals.com/product/1966-comet-falcon-mustang-shop-manual/
You would just need to install an eBook reader for your computer to read the downloaded file.
@chucktobias Thanks!
@chucktobias The brand new Cardone distributor just doesn't work on my car. I've rebuilt my old distributor and worked for 10 minutes. Then the engine stalled and I inspected it. The removeable rotor spinned further and wasn't aligned anymore.
I'm not surprised the Cardone distributor is no good, quality of new parts is in the toilet even for newer cars. As far as your old distributor, check your work. If the rotor is no longer aligned properly and the distributor body didn't move check to see if the gear at the bottom of the distributor shaft that's driven by the camshaft has come loose. Also check the mechanical advance to make sure it's not pushing the rotor out of alignment at rest.
@chucktobias No, I mean, the top of the rotor can be taken out. So I took it out and then I put it back, the car worked again and then stalled again. And so on... Should I hard-glue it?
That shouldn't be necessary. Millions of cars with that distributor were driven for decades and many millions of miles without gluing their rotors in place.
I'm pretty sure there's supposed to be a spring clip in the rotor to help hold it on the distributor shaft. Is that missing on yours? The rotor is not supposed to be a loose fit, it should take a little bit of force to install and remove it. If it's a China-made rotor possibly the dimensions are a bit off.
@chucktobias It is totally loose. It could be that the spring clip is gone. It could also be a China-made one.
Your best bet would actually be new old stock if you can find it. You can check eBay. Another possibility would be performance parts like Accel, but they tend to be pricey. Other than that you could look for the highest quality new part you can find from a source like NAPA.
@chucktobias I used the rotor and the cap of the Cardone one too. It works fine now. At least the parts of the Cardone were useable to rebuild my old distributor. I will never buy Cardone anymore though.
Unfortunately Cardone is another one of those companies that used to be good back in the day but their quality in recent years has gone into the toilet.
Now once the engine has reached operating temperature, it misfires slightly through the exhaust while driving if I accelerate slowly but it doesn't do it if I accelerate harder.
Now that I'm thinking about it. Could it be that the mixture is too rich? I'm waiting for a plastic sleeve that I ordered, so the carburetor has no choke and I got the idling mixture wrong?