Have a procharged 502 carb. The engine has about 45 hours on rebuild. The boat choked down taking off, I figured my coil wire or lanyard had came off. Towed it in and found out the distibutor gear had sheared off three teeth. Put another gear on and did the same thing, well I caught it before the teeth broke off completely. I went to take off, it started skipping. I limped back to the dock to find the new gear was wearing also. probably skipped a tooth and jumped time. The gear is wearing on one side toward the bottom. Strange! Have since taken the engine apart. The MSD dist. is fine, not warped. the cam was not walking. The cam was also not warped. Any ideas?

Check for a bent oil pump drive, check rear cam bearing.

The oil pump drive is ok. Do you thin it's possible the oil pump could be hanging up? Although, it spinns freely by hand?

Is it possible that the drive is not the correct length or binding in the distributor or pump? Is it an aftermarket drive? Can you check the alignment (at least visually) of the manifold and the pump drive hole?

For example, Crane's billet roller camshafts require aluminum/bronze distributor gears- just a thought.

Also, Some quote's from Crane:

"The main cause for distributor gear wear is the use of high volume or high-pressure oil pumps. We don’t recommend the use of these types of oil pumps. If you do run these types of oil pumps, you can expect short life of the cam and distributor gears, especially for low speed running, in street type applications. If you must run these types of oil pumps, you can increase the life of the gears by adding more oil flow over the gear area to help cool off the point of contact.

Note: distributors that have end play adjustment (up and down movement of distributor shaft and gear), Maintain a maximum of .010" end play, to help prevent premature wear."

Ha if the motor is apart take the oil pump apart and inspect those gears for were a budy of mine picked up part of his oil pump screen and it shered 3 teath of cam and Distrib but when he pulled it out the oil pump spun fine with the drill and primer. but when whe took the pump aprt it was shot. Charlie

Thanks guys, I'll keep digging. I'ts not a high volume oil pump. It really looks like something is forcing the dist. out of line with the cam, if that makes sense. The wear is on one side and angled toward the bottom of the gear. I'll take apart the oil pump. Also checked, doesen't take a bronze gear.

Your billet cam may have a pressed on cast distributor gear. If that is so, you do NOT need a bronze gear on the distributor. Sounds like you have that already figured out though. Also, the gears must be well lubed with a recommened assembly/break-in lube on a new distributor gear---this IS crucial! I run the MSD billet distributors and last year I had a problem with one of the distributors in my 540's. The gears on both cam and distributor were begining to wear excessively---they only had about 5-7 hours or so on them. We checked the distributor heigth and it was NOT correct. To do this, it requires a specially made tool that had to be purchased in order for the correct distributor heigth to be set correctly. I think the cost of the tool runs about $100. We adjusted the collar setting on my distributor and it corrected the problem.

I know you guys prob will think i'm crazy, but in another life, I drag race Buicks, and wiping out the distributor gear is very common. It typically happens from not having oil temps up fully before nailing it, running 2 think of oil, or both. When the engine is cold and the oil is thick, you are putting an ENORMOUS amount of pressure on the cam/distributor gear from the oil pump. People running blowers often don't run thermostats, so it's possible that he sheared the gears from not getting the engine up to temp. Even if this isn't what caused it, it's good advice to hold back on the sticks till she's warmed up. I'm sure there's some kind of innuendos to be found in that comment.!

I like the way you put that last remark!!!

I also lost a dist lately, but I was lucky....replaced it. flushed real good and no problem now.......per Merc, GM made a bunch of gears too soft......common problem to them, but then mines all stock except the Procharger. The engine had less than ten hours on it when it went.