Cam gear failure

[FFRSpec72]

During qualifying this weekend I had a cam gear failure. Engine started to backfire and then out right quit, had to be towed in (first time in a really really long time). Tried to start and got a backfire so knew timing, put the engine at TDC and the rotor was not facing #1, so pulled distributor and the teeth on the gear were messed up, looked at the cam gear (best we could through the block) and it looked pretty chewed up.

So only thing I can think of that would cause this is the cam thrust plate, any one else have thoughts or have seen this before ? I pulled drain plug on engine and lots of metal shavings from cam were on magnet, so pulled engine but have not torn it down yet.

Still have half the season to go here.

[skullandbones]

Tony,

Sorry to hear that. I've never seen that with the experiences I've had but only one person I know pushes his car hard and still not like on your racing schedule. He breaks things but differently. It could be that the distributor gear failed first and then messed up the cam. I've heard of them failing before. They make one that is bullet proof but it is pricey.

Good luck on putting everything back together.


WEK.

[Bob Cowan]

Does it look like this?
http://i13.photobucket.com/albums/a256/bobcowan/CamGear2small.jpg (http://s13.photobucket.com/user/bobcowan/media/CamGear2small.jpg.html)
http://i13.photobucket.com/albums/a256/bobcowan/DistGear3small.jpg (http://s13.photobucket.com/user/bobcowan/media/DistGear3small.jpg.html)

This is what happens when you use the wrong gear material for the cam.

[FFRSpec72]

Does it look like this?

This is what happens when you use the wrong gear material for the cam.

I have not pulled cam yet but looking down in the hole and looking at the distributor it looks like your pictures. Issue is that I have been running the Trickflow Stage 1 cam and stock EFI distributor, and both are steel, so there should not be a miss match in material and also I have running this combo for a since 2010 w/o failure.

[dallas_]

Tony,
I had the exact same thing happen to me.
Distributor gear was fine, about 1/3 of the cam gear teeth just broke off.

Fortunately my motor was still under warranty so I pulled it out, crated it up and shipped it back to Ford. They made it right, but would not tell me what they found or why they thought it failed. I believe it was a manufacturing problem with the cam. Not really Ford's fault but they made it right.

I've seen lots of distributor gears fail but I've only heard of about 4 or 5 instances of the actual cam gear failing. Seems to be quite a rare situation.

[FFRSpec72]

So I had some lite damage to the #1 and #5 main bearings (will need all new bearings) and cyl walls #1 and 5 (hone required), no other damage.

So the cam and the distributor gear materials match (steel on steel). I swap out between 2 engines and use the same distributor, so only thing we can think is that the difference between the 2 cam gears caused some damage (like mixing ring and pinion gears, or using same lifters on new solid cam).

[avgjoe]

Any resolution to this? Did you find a smoking gun?

[Gordon Levy]

9 times out of 10 this is caused by the oil pump. HV pumps are a nono

[FFRSpec72]

Any resolution to this? Did you find a smoking gun?

I was running a stock melling oil pump (not high pressure/high volume), the bypass valve was set high, so the tooth on cam gear was missing, cam went back to trickflow to see if there was a problem, the oil pump had no damage. So we left the bypass setting alone on the oil pump this time, I have lower oil pressure but everything looks good now, before I was running 60+ psi and now i'm running 45-50 psi