Aluminum cam gear install.

[jjk]

So i went with an aluminum cam gear on my rebuild and beside myself with worry about it being done correctly.

I set the wedge key to the 10pm position and rotated my cam to align with the mark on the crank gear and hand tightened everything down for now. Before I button up my cover could someone check my work?

[Flathead]

Looks good.

[JayJay]

There is usually a dot on the crank gear tooth that is supposed to line up with the dot on the timing gear. I can't see from your pix whether that's present, and if so where it is. But in relationship to the drawing, it looks good.

[jjk]

Thanks ya'll ,

just making sure I don't grenade this powerhouse.

[nkaminar]

The location of the aluminum gear controls the valve timing. So, check to see that both valves are open at top dead center of one of the pistons. This would be the transition from the exhaust stroke to the intake stroke. You can peak into the combustion chamber through the spark plug hole with a flash light or use a dental mirror or fiber optic probe. To get to top dead center, you can rock the crankshaft back and forth while observing the piston. There is very little resistance when the pistons are at the top and bottom. You can at the same time observe the valves. One should be closing while the other is opening.

[Marshall V. Daut]

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That drawing is misleading and will cause confusion and disappointment if one tries to align the camshaft timing and crankshaft gears' index marks as shown. The crankshaft gear's index indentation dot (or sometimes the word "Ford") is supposed to be located one tooth to the RIGHT of the woodruff keyway. The drawing incorrectly shows the tooth lined up directly in front of the keyway. I have seen this same mistake perpetuated in numerous publications, including early versions of the "red" Model A mechanic's handbook, which I own and made a correction note on that page for the next guy who gets the book.
In the 1970's and 1980's, a certain disreputable Model A parts vendor (who shall remain nameless here. ) imported a ton of crankshaft timing gears with mismarked indexes. He sold them at cheaper prices than the better vendors did, so NATURALLY, Model A people ate 'em up. For years, cars that had these mismarked gears were sluggish because the initial timing was one tooth retarded. No amount of compensation in the distributor could make up for this. I must have changed a dozen of these crappy gears over the years, much to the delight of the owners who had been disappointed by their engines' poor performance. They couldn't believe the difference in performance improvement after advancing the timing gear one tooth!
Moral of the story: No matter where the crankshaft's index mark is stamped into the metal gear, make sure you align the two gears so that the first tooth to the RIGHT of the crankshaft keyway is lined up with the dimple in the camshaft gear. If you line them up as shown in the drawing in Post #1, you'll be the caboose in any Model A club tour.
Marshall

[Dan McEachern]

Now - check the backlash between the cam and crank gear! You should have a minimum of .003" backlash with the valve springs installed.

[JayJay]

Originally Posted by Marshall V. Daut

That drawing is misleading and will cause confusion and disappointment if one tries to align the camshaft timing and crankshaft gears' index marks as shown. The crankshaft gear's index indentation dot (or sometimes the word "Ford") is supposed to be located one tooth to the RIGHT of the woodruff keyway. The drawing incorrectly shows the tooth lined up directly in front of the keyway. I have seen this same mistake perpetuated in numerous publications, including early versions of the "red" Model A mechanic's handbook, which I own and made a correction note on that page for the next guy who gets the book.
In the 1970's and 1980's, a certain disreputable Model A parts vendor (who shall remain nameless here. ) imported a ton of crankshaft timing gears with mismarked indexes. He sold them at cheaper prices than the better vendors did, so NATURALLY, Model A people ate 'em up. For years, cars that had these mismarked gears were sluggish because the initial timing was one tooth retarded. No amount of compensation in the distributor could make up for this. I must have changed a dozen of these crappy gears over the years, much to the delight of the owners who had been disappointed by their engines' poor performance. They couldn't believe the difference in performance improvement after advancing the timing gear one tooth!
Moral of the story: No matter where the crankshaft's index mark is stamped into the metal gear, make sure you align the two gears so that the first tooth to the RIGHT of the crankshaft keyway is lined up with the dimple in the camshaft gear. If you line them up as shown in the drawing in Post #1, you'll be the caboose in any Model A club tour.
Marshall

Marshall - what exactly do you mean by "...to the RIGHT..."? Do you mean clockwise or counterclockwise? For example, on mine (see photo that I took while disassembling) the dimple on the crank gear is about a half tooth clockwise from the keyway. This looks to me to be in accordance with the drawing that JJK provided, which you're saying is incorrect??? (I have no history on this crank gear other than the engine was rebuilt some time ago.)

Does anyone have an original drawing of the crank gear that might shed some light on this? Dan McEachern, you manufacture these gears, any thoughts?

Thanks for this, and all your, insight and perspective.

[nkaminar]

It is so easy to check the timing by noting the valve action as discussed in Post #5. If the head is off it is even easier as you don't have to peek in through the spark plug hole. Why not check the timing this way? It eliminates any mistakes in interpreting how to align the gears using instructions or drawings. It relies on first principles and not secondary information.

[jjk]

Great info guys thank yall for taking the time to walk me through this. I set went ahead and bolted down the cam gear and set the cover up to align the dimple and check for TDC. I do have the oil pan off which makes it easier, and I have my lifter cover off still, so I have a full view of the internals.

I set the cover up and rotated the crank until my alignment pin slipped into position and looked at cylinder one from the bottom which looks to be TDC. If you look closely at the crank gear, I used a silver Sharpie to mark the index point on the gear tooth to help visualize position in relation to the cam gear.

Ive also included a side shot of the lifters at TDC.

[JayJay]

Sorry, photo referred to in #8 didn't upload. Here it is.

[Marshall V. Daut]

Yes, Correct.
M.

[Dick M]

The mark on the crank gear is sometimes partially hidden behind the oil slinger. Look closely and you will find it. Line the cam gear marks with the crank gear mark and you are in business.