Anyone Have Problems With A Melonized Distributor Gear?

[32witha409]

Running a melonized gear on my OEM 348 distributor with my Comp roller cam. Wondered if anyone has had issues with them under mild conditions?
Cut the filter open last weekend while doing the first oil change and got a good amount fuzz on a magnet after straining the thinned filter contents through a coffee filter.

Trying to decide if it was from the rings seating on a newly honed bores or if I need to pull the dizzy. I did lean on it early in the break in, so the rings were seated quickly.

 

[Ishiftem]

I wouldn't worry about a little fuzz. The melonized gears work well. You just can't run them on certain cam cores or cam cores with certain heat treats. Always best to ask the manufacturer.

 

[Murphdog]

I received this email from Comp Cams this morning. I inquired about a BBC hydraulic roller that was ground on a cast core, not billet, that had some fuel pump lobe wear and was asking if there was any repair available. I pulled this out of an engine years ago, I don't remember it having a bronze tip pushrod. Must be something with the heat treat since it was a roller. Don't remember what it had for a distributor gear either.
Jeff

You cannot run a stock fuel pump rod with those cams. You will need one to use one that has
either a DLC coated end or one with a bronze tip.

Most iron gears should work with these cores as they are a treat cast core. But a melonized gear
is preferred.

 

[63impaloligist]

Comp roller cams, hydraulic usually have a cast gear pressed on, which explains their higher cost. But the solid roller cams are billet and require the bronze or melonized gear. A phone call with the part number should get you that info

 

[dakota tom]

A lot of the small metal flakes can come from the valve springs.
I've expoxied a magnet on the head to catch that. One time caught a valve keeper on one.

 

[La Hot Rods]

A lot of the small metal flakes can come from the valve springs.
I've expoxied a magnet on the head to catch that. One time caught a valve keeper on one.

 

[32witha409]

Thanks all for the information.
I did verify with Comp before the build that this cam was indeed a steel billet cam and needed the melonized gear. I normaly would use a bronze gear for racing but read that they don't last well on the street.

Guess I'll see if it is better next oil change.

 

[Skip FIx]

I know lots of the Pontiac guys are using a composite gear(by BOP) or a bronze gear-no melonized made for Pontiac. Lots of guys like the composites but often will break in with a bronze or jeweler's file sharp edges off the cam gear.
There are different quality bronze gears so use a good brand name. I have a bronze in my 470" MSD brand and distributor "ready to run".

How many of you with billet rollers are using a mechanical fuel pump-what rod? Bronze tips wear out?

 

[32witha409]

I'm running a bronze tipped rod from howard cams. Ordered a Comp bronze tipped rod, but it came with the DLC coating and sent it back. Might be ok for a while but that DLC coating is only .0005 thick max and it's not indestructible.
Time will tell on wear.