Distributor gears?

Why are so many people having distributor gear problems? This seems to have escalated in just the past few years. What has changed? I think we all know to use a bronze gear with an after market roller cam. Leaving that out of the equation, then what is going on? Is it only happening with Ford motors, or are othe makes experiencing this problem also?[img]/phpBB/images/smiles/icon_confused.gif[/img][img]/phpBB/images/smiles/icon_confused.gif[/img]
[addsig]

Correct me if I am wrong... If I recall the Steel gear is for a roller cam and an Iron gear is for a standard flat tappet cam... Not sure on the bronze gear though.... I could be wrong but that is what I recall being told....
[addsig]

I think we are both correct. You can use either a bronze or a steel gear with a roller cam.
[addsig]

What is the purpose of the bronze gear... Why would they make two for the same application... Is one better then the other....

Sorry to steal your thread, but well were on the subject of dist. gears... I need to swap out my iron gear for a steel gear on my MSD billit dist... Looks like I will have to press it off the distributer... Any tricks to doing this?
[addsig]

My CompCams Xtreme Solid street roller uses an iron gear on the distributor. I was told that is the same core as a flat tappet but uses a hardening process on the lobes much like a crankshaft journal is hardened. You guys need to be sure what you have before using any kind of dist. gear.
[addsig]

Billy ... I would take it to a machine shop and have them press it off ... and also press the new one on.

Be certain that they press the new on to the the exact correct depth, not sure what engine you have, but for a 335 and 385 series engine it is a flat "FOUR" inches.

It is not uncommon for folks to just try to line up the holes in the gear with the holes in the shaft and them "assume" it's got to be correct ... wrong, wrong, wrong!

Press it on the the precise correct depth and then re-drill the holes in the shaft using the holes in the gear as your pilot ... then re-pin it ... you can even double pin it if your geas has two sets of holes ... many do.

Machine shop charged me $10.00 to do it and eliminated any chance of me damaging it using caveman techniques [img]/phpBB/images/smiles/icon_wink.gif[/img]

BTW ... Bronze geear is softer and will not damage steel cam ... or particles in the oil damage the engine for that matter. Steel gears have only been around for a relatively short time and bronze was the deal before the steel gears came out.

Bronze gear is consumed during normal operation so it must be checked and changed as needed ... Not a big deal on a "Hot Rod", but a royal pain in the butt on a daily driver ... If you get 1,000 to 1,500 miles out of a bronze gear, you done good.

Larry Madsen
Las Vegas Nevada



<font size=-1>[ This Message was edited by: monstermach on 11/10/02 8:54am ]</font>

<font size=-1>[ This Message was edited by: monstermach on 11/10/02 9:00am ]</font>

Use a cast gear for flat tappet cams.
Use a steel gear for hyd and "street" solid rollers.
Use a bronze gear for "race" solid rollers.

All the rollers are made of steel, but there are two different kinds of alloy steel used.

For a Comp Cams roller use a steel gear if the roller cam part # ends in 8 and use a bronze gear if it ends in 9.

A trick to double the life of a bronze gear: There is a threaded pipe plug in the block just behind and above the distributor gear. Remove it and drill a very small (1/16 or less) hole in the center of the plug and re-install. The plug is in the lifter oil galley and it will now provide a pressurized stream of oil directly to the distributor/cam gears. Never do this with a hyd cam. Soild only.

I had a bronze gear in my old duraspark dist with hy roller cam, went south this summer, thought i blew the motor, it lasted a few years though, now on my billet dist it has a cast gear, so im worried about that now, it was dynoed at 6000 grand 6 runs, so i think its ok until i change my cam, even the cam companys dont know what gear is on the cams, i asked lunati he said hy rollers might have cast gears on their cams?

That is correct ... A roller cam may have a cast iron drive gear, it's a cast iron section pressed on the cam for the distributor gear to work with ... if this is how your cam is set up you use a "factory style" cast iron dist gear.

I know "Comp Cams" makes some that way and I can tell you for sure that my "Crane" mechanical roller cam in my 351C 4V is Steel and is using a steel dist gear ... My "Crane" hydraulic roller cam in my SBC 350 has the Cast Iron drive on the steel roller cam and is using a factory style cast iron dist gear.

Everyone is correct about "You need to know for sure what the drive on the cam is and match (material) to the dist gear" ... But, for my purposes I can't imagine why anyone would use the bronze gear with the other two options available, especially on a street driven car [img]/phpBB/images/smiles/icon_wink.gif[/img]

_________________

Larry Madsen
Las Vegas Nevada



<font size=-1>[ This Message was edited by: monstermach on 11/11/02 12:04am ]</font>

i have been running a bronze gear on my street/strip solid roller for five years now with a duraspark. its out on the bench right now and i am changing over to an msd dist. if the gear wasn't so loose on the msd it would go back in its in that good of shape.