Timing the 30 model A engine

3

30standardcoupe

Member
Is there a step by step on how to time the model A engine? My engine runs pretty good, but it really lacks power at top end and backfires when shifting gears. My advance/retard lever is in the full advanced position.

I have seen on youtube where a gentleman made a pointer and used a timing light, but how do I know where to set the timing or what degrees?

I am familiar with V-8 engines, how to disc the vacuum advance, and such, but the model A engine is my first rodeo, so if you have advise on how to get the timing really close please share.

TIA
Clay
 
30standardcoupe said:
Is there a step by step on how to time the model A engine? My engine runs pretty good, but it really lacks power at top end and backfires when shifting gears. My advance/retard lever is in the full advanced position.

I have seen on youtube where a gentleman made a pointer and used a timing light, but how do I know where to set the timing or what degrees?

I am familiar with V-8 engines, how to disc the vacuum advance, and such, but the model A engine is my first rodeo, so if you have advise on how to get the timing really close please share.

TIA
Clay
Click to expand...

There is part of your problem.

Bob
 
Stop the engine, remove the timing pin from the front of the timing gear cover, turn the pin around and insert it in the hole it came out of, hold it in snugly, crank the engine over slowly by hand, when the timing pin goes into the dimple in the timing gear, stop turning, set the points to just starting to open for # 1 cylinder. Simples.
 
katy said:
Stop the engine, remove the timing pin from the front of the timing gear cover, turn the pin around and insert it in the hole it came out of, hold it in snugly, crank the engine over slowly by hand, when the timing pin goes into the dimple in the timing gear, stop turning, set the points to just starting to open for # 1 cylinder. Simples.
Click to expand...

Also have the spark lever in the fully retarded position.
 
If the timing is set the way Marco shows, then it doesn't matter where the spark lever happens to be.
With the timing pin in the cam gear detent, line up the TRAILING edge of the rotor to the #1 contact.
 

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All of the above are most helpful as well as volumes written on this subject, diagrams, videos, etc., etc.; i.e., (a) With ignition switch OFF, first adjust point gap; (b) Retard spark with spark lever all the way up; (c) Crank engine until timing pin slips in; (d) Unscrew distributor cam screw and rotate distributor cam until points just begin to open; (e) Tighten distributor cam screw.

Not always mentioned is the possibility of obtaining inaccurate timing caused by worn parts and loose play; i.e.,

(1) The oil pump drive gear assembly, (part no. A-6542) could be worn & loose on a
worn spiral gear in the cam shaft; (2) The distributor upper and lower shafts, (part nos. A-12178 & A12249), could be worn & have loose play; (3) The rotor on the distributor shaft could have loose play.

Notice that the engine turns the distributor shaft counter clockwise; but when the distributor shaft screw is tightened clockwise, some get confused with back and forth shaft movement, loose play, and "exact" cam position.

To try to avoid confusion, and "after" tightening the distributor shaft screw and to try to answer your question:

"so if you have advise on how to get the timing really close please share."

Maybe try this second ride in your Rodeo after the first ride:

(I) Again, retard spark with spark lever all the way up; (II) Again, crank engine until timing pin slips in; (III) "NOW" verify and "double-check" that your points are just about to open; (IV) If YES, good to go ...... if NO, loosen distributor cam screw and re-set timing.

Hope this helps.
 
I use a continuity meter and the advance lever to check if the points "are just about to open".

I carefully find the point where the timing pin slips in - I only turn the engine clockwise.

When adjusting the rotor, I only turn it clockwise, and hold well while tightening.

To evaluate if the points are opening properly, I start with the fact they should be closed - so I have continuity thru the points.

If I move the advance lever "3 clicks down" - or about 3/16ths of an inch since my clicks are worn away - points should open. Returning the advance lever back up and they should close.

I then turn the engine another complete revolution and find the timing pin location again and check if the points open 3 clicks down - if so, I button it up.
 
Also check 1 more thing. Take your finger and see if you can push the shaft side to side making your points gap change. If you can,then time for new bushings.
 
Tom Wesenberg said:
If the timing is set the way Marco shows, then it doesn't matter where the spark lever happens to be.
With the timing pin in the cam gear detent, line up the TRAILING edge of the rotor to the #1 contact.
Click to expand...

Tom, your comment confused me, as I have always timed my A's with the spark fully retarded. But admittedly I had never looked at Marco's method. Now, tomorrow, I will check the timing on my Tudor using Marco's site for reference, and see if I get a different setting.
 
700rpm said:
Tom, your comment confused me, as I have always timed my A's with the spark fully retarded. But admittedly I had never looked at Marco's method. Now, tomorrow, I will check the timing on my Tudor using Marco's site for reference, and see if I get a different setting.
Click to expand...

I usually set the timing as described in the owner's manual, but Marco's method will get the same results and you don't have to worry about where the spark lever is, or squint to see the points open.:)
 
Wonderful if you're running lean... Fuel wise? See if opening your GAV makes any difference? A simple thing to try. I experience similar symptoms and it was a lean fuel issue.
 
Marco's method is simple and interesting.

Although not accurate, accuracy is not required except for the fact the timing needs to be ATDC for hand cranking and for life of electric starter. The Marco method accomplishes this.

Being retarded will effect idle speed, but that can be corrected other ways.

Timing is set by feel while driving, so very easy to compensate for initial being retarded.

I do not think there is any reason at all to have any type of accurate initial timing, except for being ATDC, whether that is a couple degrees or 10.

Interesting how the Model A motor does not have any transition off idle issues?? Usually retarded timing is horrendous for this!!
 
"I do not think there is any reason at all to have any type of accurate initial timing, except for being ATDC, whether that is a couple degrees or 10."

i know who won't be timing my car
 
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