Shredded the timing gear...but how?

tbirdtbird said:
It is hard to imagine the valve gear in a running engine seizing.

If a car sits for years and the valves seize, then no part of the engine will rotate (metal or fiber). It will be obvious that something is wrong but no damage will occur.

After the Model A years there were many engines with timing chains and metal gears. The same concept would apply I would think.
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I figured the same thing. So the thought that there is a need for a gear to strip to save the rest of the engine does not really exist,
 
Supplier of gear went offshore with a good timing gear in hand, looked around for the lowest cost factory and said, "Make these for me just as cheap as you possibly can so that I will make a huge profit". Problem is not so much the producer, as reputable offshore companies can meet the highest quality standards, but the US businessman who specs a cheap product.
 
Since my first Model A special Coupe in 1960. Have never seen a camshaft lock up on a Model A. Have seen plenty of striped fiber gears. I do not want all that fiber parts in my oil pan and valve chamber.

Back in the day a lot of trucks used a alum gear. Even then we use to change a lot of fiber gears. No more fiber for me. My coupe has over 20'000 miles on a metal gear. It sounds just fine.
 
tbirdtbird said:
did this occur with the engine already running? or after car was sitting a while
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Restoration completed in September, 2014. Had close to 500 gentle miles on the car at that time. Since September, regular drives and tours have added another 1,500 miles. Odometer reads 2,049.7. I was out doing some in-town driving that day and was on my way home. I live 2 miles out of town so was driving 45 MPH when it failed. Was at least able to coast close to home and didn't require a tow.
 
First i will tell you that i am not a trained mechanic. But i am thinking that when the gear stripped it would have immediatly stopped the engine. That being the case, i might not be too concerned about fiber particles being pumped through the oil passages and plugging. Iwould think a very thorough cleaning of the pan and gear area would be sufficient.
 
I don't see how broken teeth would block any passages because the passages are from the bottom of the valve chamber to the main and cam bearings. I would be concerned with having to remove the oil pan and clean it out. Removing and replacing the oil pan with the engine in the car is a job that I for sure don't want to do. The screen on the oil pump would keep teeth out of the pump and passages. Enough broken tooth particals could block the screen on the pump and cause problems though. Its simple for me, I won't be using fiber gears in my engines .
 
Re: Shredded the timing gear...but how? (UPDATE)

I have forwarded images of the failed gear to Richard Fallucca of AER. Richard says this is the first gear of his that has failed. He said it's not a matter of gear mesh as the images don't show the normal wear pattern of a tight fit. The fact that the teeth have simply snapped off indicates failure.

The failure has him just as confused as the rest of us. He can't believe anything foreign is in the engine causing the gear or valves to seize as it's a fresh rebuild. Also, the engine turns very easily with the crank with no apparent resistance.

He does not recommend pulling the engine at this time. He recommends a new gear and unfortunately dropping the pan to clean out the broken teeth. Richard does not recommend metal gears as metal slivers could peel off and get into the engine.

I'll be reviewing past threads and looking into quality alternatives to a fiber gear before I reinstall.

Thank you all for your advice and condolences!

Dave
 
I would go through the oil pump while you have the pan down. The screen will be plugged. I think shattered is a better description of what I see to describe the damage to the timing gear. I would also go so far as to pull the valve cover and clean out the wiers looking for small particles. Yea, I will get flack for suggesting this, but that is what I would do. What does the rebuilder say?
Bob
 
Just one (1) probable cause:

1. Maybe the guy mixing the fiber batch to make these timing gears dropped his grilled cheese sandwich in the mix.

2. Then, you just happen to get the gear with the encapsulated cheese sandwich.

After 50 or so above possibility guesses as to what may have happened, 1 & 2 above might shed light on a clue to this mystery.

On a serious note, what ever you do, just sincere best wishes that all turns out well.
 
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I just looked in Bratton's catalog and see they don't offer the cheap fiber gear.
Just for one's reputation I too would not sell nor install the cheap fiber gear.

I might be wrong, but from the picture, isn't this the cheap fiber gear, rather than the stronger laminated gear?
 
What ever the material is, Richard Fallucca of AER has them made specifically for him. I would assume he does not think they are the cheap fiber gears, but only he knows I guess.
 
I know that installing a matched set of crank and timing metal gears is the best situation, but has anyone installed just Dan's or Bill's high quality metal gear with their existing crank gear and been satisfied. In reading the posts it makes a person nervous with a fiber gear. My engine is a fresh touring rebuild with a fiber gear also, and it would really be nice to not have to pull the crank.
 
Yes, I have installed Dans bronze cam gear and others aluminum and bronze gears without installing the crankshaft gear and have had no detectable noise or other problems. People have all kind of ideas about this. A person must make their own choices . If the crankshaft gear isn't pitted and looks good I usually just use it . You do not have to remove the crankshaft to replace the crankshaft timing gear, I've done it and used a three arm gear puller. the oil pan must be removed though . When I installed my first Dan gears in my AA we installed both gears with the motor in the truck. When the cam gear stripped on the coupe it hadn't been that long since we had overhauled it and installed a new fiber cam gear and a new crankshaft gear. The crankshaft gear still looked good as new and I could see no need to go to all of the trouble of replacing it. In that case I just installed a new Dan cam gear. My roadster showed around 10.000 miles on the crank gear so I just installed a new bronze cam gear from Snyders just for security. The fiber gear hadn't stripped on the roadster . I was installing a 3/4 race Winfield cam and figured it was a good time to go ahead and install a good reliable bronze gear .
 
I can't imagine a timing gear failure with so few miles on the engine. I was there when the cylinder head was removed after the 3rd gasket failure - part of the gasket was in the combustion space, burned and blew the media between cylinders 3 and 4. At that time, there was no sign the valve interference with the cylinder head or gasket.

I have had 2 timing gear failures - one because the aluminum hub let go, and the other one that chewed the gear like this. I was on a tour when it failed because there were some pits on the steel lower gear and I didn't get the clutch in right away. Since then, a lower gear was installed and I haven't had any problems yet (10,000+ miles) But if I do, I will use a metal gear.
 
" Richard does not recommend metal gears as metal slivers could peel off and get into the engine."

Not sure how to weigh in on this remote concern.
However, if you have sunk some $$$$$ into a fresh build from anyone, we have to assume you had the foresight to install the oil filter package to protect your $$$$$$ mains. If so, I propose that any potential issue with metal slivers has been thus properly addressed.

Also as earlier mentioned I have also installed a new bronze gear and left the existing crank gear in place with no problems at all. And I do a lot of touring.
 
When I did mine, it was a no-brainer. The engine was already out & apart. I noticed that the fiber timing gear (on a 2,500 mile engine) was missing a couple of teeth. Among other things, I was putting in a new Stipe IB330 cam. So, when ordering the new Bronze timing gear from Dan-the-man, the matching crank gear was only $35 additional and no additional freight. ----- cheap insurance ------- (and no noise out of the peanut gallery)
 

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