I let my truck sit too long without driving and it appears the carb is gummed up. I went out and pulled it today. I finally broke down and bought a timing light. I checked the timing and it shows 0 degrees. Will it run ok at 0? It idles and drive but the carb is plugged up. I had the engine rebuilt a few years ago and I had it set up and timed at that point by a mechanic. I have no idea what it was set at. I had a new cam installed on the engine. What should I be looking at for my initial timing? I see Ford recommends 4-8, I wasn't sure how much that would change with a rebuilt motor and mild cam. I have a mechanical advance distributor. I am going to clean the carb over the next few days, but I wanted to start fresh and learn to set timing and the carb. I was thinking I should verify the 0 mark on the harmonic balancer is at TDC. It was a reputable shop that rebuilt the engine.

 

I would fiddle around with it and advance it to 6 degrees while running. See if it gains RPM. If so, adjust the idle and repeat, moving the timing back and forth for the best idle.

Usually on a regular fuel engine like that, you can go 8 degrees and still not have a pinging problem. You'll have to run it to see. Some here have run 360s out to 10 degrees.

You can determine TDC by pulling a plug and "feeling" the piston with a short piece of wire.

 

Ok, I think I really need to ensure it is at TDC before I go fiddling with it. Is 700-800 ideal idle RPM?

 

Without searching forever I find 650 hot for a manual trans and 550 hot and in drive for automatic.

So if you can make it idle smooth at 700 you'll be ok.

If it won't idle smooth and have to go to 800 maybe recheck the carb passages.

 

If you've got a dial back timing lite would suggest all in mechanical timing at 34°-36°. That should put you in the 12°-14° range at idle. I run 14° initial with 10.5:1 compression with no risk of detonation even when towing. Elevation is also factor for me being at 5300' and will usually pull about 2° out when at low elevations. If you don't have a dial back timing light, start at 9°ish and take it for a whirl. Advance it 2° and repeat. If/when it starts to knock, back off 2°. You'll feel a difference in the pedal as well at each run and just run it where it's the happiest.

 

I moved from sea level to 5000' recently. The motor work and setup was done at sea level, so it may need to be changed. I bought new jets for the carb cleaning. When I face the engine the balancer has an engraved mark of 0, all the hash marks are to the left of the 0. Wouldn't these marks be after TDC? There is a white line at 12 degrees, but I believe it would be after TDC. But if that line is TDC it would be set at 12. I really need to find TDC and a good mark. I watched a few Youtube videos last night and I think I will use the thumb pressure method and a stick to ensure I am on the compression stroke

 

Yes, sounds like those marks are actually after TDC. If it's an old, used balancer then I recommend a new one. Old ones with rotted rubber don't do their job protecting the engine very well.

I believe personal preference and custom engines will dictate timing. As mentioned, initial timing between 6 and 12 is a good start. Sounds like you have a little customization (i.e. "mild" cam) so you and your engine may like timing adjustments that differ from the factory distributor. I've never actually worked on a factory style distributer. I've always had aftermarket distributors because it's easy to adjust the curve for total time and the timing advance at various rpms. I like to get the idle good in terms of carb idle screws and initial timing. Then take it out on a deserted strip of road and floor it with a stop watch. Find out what timing curve gives your best acceleration without pinging. In other words, you adjust the amount of timing advance and what rpm the total time occurs. As mentioned, total time around 34-36 is about right for cast iron heads. You may want to adjust the distributor so that comes in soon enough for power but not too soon to cause pinging. As an example my engine with mild cam and aluminum heads and I like 12 initial and 31 total at 3000 rpms. Your engine may like more total time at lower rpms...or vice-versa...won't know until you try it.

Also, the level of cam will influence your idle preference. As mentioned, a factory engine will idle around 650. My engine, with a "mild" cam likes 800.

You kinda have to take your time and play with it...see what you and the engine like.

 

If you have a points distributor, you need to check and set the points first. Changing gap (dwell) will change the timing. That could explain why your professional rebuilt is sitting at 0 degrees. I doubt they would set it that way.
Roughly checking TDC with a stick is fine, however marking TDC with a stick is pretty inaccurate. As you travel over the TDC point, the piston does not move up and down too much, as it traverses some degrees and it's hard to nail the zero mark. I would suggest the piston stop method, or use a travel indicator instead of a stick.
I'd start at 8 degrees. Since you have a mechanical, you should have a direct advance map from the mfg. If not, you can rev it while watching with the light and map it yourself.
I would consider a vac advance dist for better street/hwy daily driving, since it takes into consideration engine load to set advance, instead of only RPMs.

 

I did not save any of the info on the cam from the engine builder. I put a Petronix ignition in it so no points. Tomorrow I plan on starting on the carb. I may need to get a timing tape

 

Pertronix is great. If you swapped it in w/o checking timing then, that could explain why timing is off now.
I wasn't considering cam map, but distributor map. Since it is mechanical, it will have a specific advance map relative to rpms.

 

I got the truck running pretty good with a tuned up carb. I had a helper today and ran the rpm up and the timing did not advance. I pulled my distributor and there was not any springs inside. It does not seem to be set up with any advance mechanisms. It is not a vacuum advance. Do I need to get a new distributor to get this thing to advance? I drove it at 70mph on the freeway today.

 

The springs are located under the plate inside the distributor so you can't see them without disassembling it. More than likely the plates are just stuck. Can spray some PB blaster or similar between plates or if comfortable, disassemble and clean/lube as needed. Once you get everything cleaned up may have to reset timing since possible plate stuck somewhere in range of travel/advance as it currently sits.

 

Thank you, Hopefully I can tear into it in the next few days

 

Check that rotor really closely. If you zoom in on the picture, there looks to be a flaw in the plastic. Hopefully not a burn through. Worth a cleaning and quick check from the underside. Don't want that spark waisted down the center of the distributor.

I only had Chevy's do that , but with the quality of today's parts, it's worth a check...