Cam timing gear secrets?

[spinelll]

Is there a secret process to installing the cam timing gear (radiator intact)?

I was expecting to fight with the cam nut but that came off without issue. Pulling off the old gear however took 2 pry bars and resulted in its complete destruction. Hold that thought.

The new gear is oriented correctly and it looks like the timing marks are (will be) lined up. But it’s currently pressed in only about half way (in relation to the pins). I made a jig (really just a wooden disc with a hole in it) to place against the gear so that I have something to lightly tap on. Keep in mind that with the radiator in place you can’t really “swing” a hammer in there. Also, I slipped some 3/8 rigid insulation behind the rad fins to avoid damage so the gap is even more narrow. Do you have to “wiggle”, so to speak, the crank gear as you apply pressure? If my timing marks are off by a tooth, there no way that gear is coming back out without damage (See “hold that thought” above). I was under the impression that it slipped in there a little easier.

Is the fact that it’s so tight an indication of anything?

Thanks
Leo

[Greg Jones]

I feel your angst. I have done this many times and find the best way to get the new gear on is to first make sure everything is aligned properly, i.e., the gear mating marks on the cam and the crankshaft gear. Your cam needs to be in the correct position of course so the pins line up properly. I don't hammer the gear on, I get it lined up properly and convince myself that everything is in the right position, then start to tighten the nut down. As you tighten it the pressure will seat the gear on the pins. In essence, you are pressing the gear on. Use a mirror to check and recheck what is happening. I had one of those timing gears with the timing mark off by a tooth. Therefore I had to get the cam in the right position vs. the crankshaft, which I did through tiny movements of the crankshaft. Hope this helps somewhat.

[Wick]

Dont forget to install the cam button and spring.

[Patrick L.]

Just like the fellas said, it'll go on. Again, just make the marks are aligned. Stick a soft rag between the gear teeth and TIGHTEN the nut. Pour a lot of oil over the gears and plunger.

[spinelll]

Originally Posted by Wick

Dont forget to install the cam button and spring.

Wick
You're referring to the cover right?

Originally Posted by Greg Jones

...then start to tighten the nut down.

Greg
I was ready to try that and then considered that perhaps the nut would chew up the middle gear body a bit.

[Marshall V. Daut]

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I just went through this a few days ago. Firstly, though, I had one h#ll of a time getting the camshaft nut off, even after heating. I finally had to chip the old timing gear away because the nut was on so tight, to the point of digging into the fiber gear. Some REAL smart former "restorer" must have used a pneumatic wrench to tighten that nut. Moron! The nut still came off with great difficulty. A new nut with a modern hex head tightening lug will be installed to spare the next poor schmuck who will have to change gears someday.
Anyway, that, of course, threw off the camshaft alignment with the crankshaft timing gear because the camshaft spung a bit while the fiber gear was being chiseled off and the nut loosened. I turned the crankshaft so that its timing mark was approximately where it should meet the timing gear mark. Then I used a screwdriver blade between the camshaft's nose and its dowel pins to turn the camshaft, keeping in mind that the valve springs preclude simply turning it by hand. I kept eyeballing the relationship between the crankshaft gear timing mark, the camshaft dowels and the timing gear holes, and timing mark orientation. When I thought all the heavens were in alignment, I attempted to slip on the timing gear - and ran into the same problem you did. It just would not slide over the camshaft snout. In nearly 50 years messing around with Model A's, this is the first time I had experienced a no-go situation here. A few taps with a mallet produced no appreciable inward progress of the gear. So, I pulled it back off and with a rattail file, I went around the inside circumference of the hole and filed it ever so slightly larger. My reasoning was that once the gear was seated over the two dowel pings, the small wedge on the camshaft end had burrowed into the gear and the nut was tightened, the gear was not going to move. A couple attempts at filing and trial fitting resulted in an acceptable (but not loose) fit over the camshaft snout. Even though I had been paying attention to the position of the valves in #1 cylinder, I discovered that the camshaft had moved (or I had moved) 180 degrees opposite of where it should be: the dowel pins did not line up with the holes in the timing gear. It's impossible to put the gear on 180 degrees off, so that told me I needed to rotate the camshaft 180 degrees to fit the new gear in place and be in time. Fortunately after doing so, the gear could be gently tapped over the dowel pins and the timing marks lined up. Just be sure when eyeballing the timing mark alignment that you allow for the angled cut of the gears, which changes the position of the teeth when the gear is driven home, usually by one or two teeth. Kind of an optical illusion. Anyway, the gear seated against the camshaft front and is tight on the camshaft, even before the nut is put on. It ain't moving at all. Had I forced the fiber gear into place with a BFH, not only would I have had to remove it again because it was 180 degrees off, but I probably would have compromised the integrity of its center with repeated hard whacks. There was also the possibility of simply breaking the gear by splitting it at the hole. It was imperative in this case to open up the timing gear hole ever so slightly to slip over the camshaft snout. I'm guessing that the manufacturer is making the new gears a bit undersized here. It's a quality laminated gear, not the cheap one or the dreaded two-piece hunk of junk. The camshaft is original, so the problem must lie in the gear itself, as you and I both discovered. independently.
Try what I have explained here and your gear will fit o.k. and not move.
Marshall

[Gary WA]

Originally Posted by Patrick L.

Just like the fellas said, it'll go on. Again, just make the marks are aligned. Stick a soft rag between the gear teeth and TIGHTEN the nut. Pour a lot of oil over the gears and plunger.

Do You want to oil the timing gear???

[Tom Wesenberg]

Originally Posted by Gary WA

Do You want to oil the timing gear???

Oil or grease will work, but you sure don't want to start out dry, especially on the plunger. When the engine is running there is a flood of oil going over the front dam and onto the timing gears.

[SteveB31]

Forgive me if this sounds too simple, but I took my radiator off today to install a new one, and it took less then 20 minutes to remove the radiator. Why not take it off ad it makes your timing gear install much easier.....

[Tom Wesenberg]

Originally Posted by SteveB31

Forgive me if this sounds too simple, but I took my radiator off today to install a new one, and it took less then 20 minutes to remove the radiator. Why not take it off ad it makes your timing gear install much easier.....

Glad you posted that Steve because I was thinking the same thing.

[Patrick L.]

Originally Posted by Gary WA

Do You want to oil the timing gear???

Yep. Don't start it dry.

[western77]

Be sure and check the condition of the gear on the crank. If that is worn or pitted you will be doing this all over next winter. JB

[Patrick L.]

Originally Posted by western77

Be sure and check the condition of the gear on the crank. If that is worn or pitted you will be doing this all over next winter. JB

Yep, thats true. Changing the cam gear is easy, not so with the crank gear.

[Purdy Swoft]

Use metal timing gears and its not likely that they will fail in your lifetime. By all means, remove the radiator first. Replacing timing gears is one of the worse pain in the ass jobs that I can think of, just telling it like it really is. If the crank gear hasn't been exposed to the elements, its not likely that it will be rusted or pitted. I usually just replace the cam gear with either bronze or aluminum. I remove the original cam nut with a chisel and hammer and replace it with the modern hex style nut that is now offered by most model A parts venders. I can see no sense in reusing the difficult to remove and replace original cam nut, after all its hidden.

[spinelll]

Originally Posted by SteveB31

...Why not take it off ad it makes your timing gear install much easier.....

Agreed it would be easier. But I'm addressing a bunch of other winter projects at the same time and have parts everywhere. I also want to paint the timing covers but with the bitter cold, that task will be delayed. I just don't have the floor space to keep a hood, grill and radiator in my garage right now.

[CarlG]

Originally Posted by spinelll

Agreed it would be easier. But I'm addressing a bunch of other winter projects at the same time and have parts everywhere. I also want to paint the timing covers but with the bitter cold, that task will be delayed. I just don't have the floor space to keep a hood, grill and radiator in my garage right now.

Where there's a will -- there's a way!

Mama might not like it, but you could brush paint the timing cover on your kitchen table, cure it in the oven.

Hood, grill & radiator would fit just fine--throw a tarp over your rumble seat and store them there. No extra floor space needed.

[spinelll]

Originally Posted by Greg Jones

...I get it lined up properly and convince myself that everything is in the right position, then start to tighten the nut down. As you tighten it the pressure will seat the gear on the pins.

Yep. Worked like a charm.
Thanks.