L98 distributor gear, which one is correct?
 

Is there any easy way to tell if the gear on the distributor is the correct one for a roller cam?

Is it magnetic or lack of magnetism that can help determine if it is the correct one?


I have a distributor for the ECM, just need to know if it has the correct gear on the shaft.

Re: L98 distributor gear, which one is correct? (gene284)
 

:cheers: I kad the same problem years ago!

Wish I could remember the answer!

But I can tell you this, if your existing gear is showing wear at the teeth, it is the wrong one.

One has a grove and one doesn't...juist wish I could remeber which is which :rolleyes: :confused:

:seeya

:steering:

Re: L98 distributor gear, which one is correct? (gene284)
 

If the camshaft is a steel billet core (which I doubt since they're primarily used for full racing applications) you need a bronze gear. They wear pretty quickly so need to be checked often and replaced as needed.

All other camshafts take an iron gear, but there are at least two different types, more if you consider the ones that the camshaft companies offer.

I had a distributor gear wear problem beginning in 2002 and I went through 3 gears. One gear wore so badly that the car actually quit while I wad driving down the road. I solved the wear problem with a Melonized gear from GM.

If I had it to do over, I would go with the gear that the camshaft company recommends. Presumably they have done the tests and know which materials are compatible.

I suspect high pressure oil pumps contribute to accelerated wear too, even though the pump makers claim they don't.

If you install a new gear, be sure to lube it well before you drop in the distributor. Use an old toothbrush and some moly lube to really work the lube into the metal.

Crane recommends cutting a groove in the distributor shaft to allow pressurized oil to spray on the gear. I did that too.

Jake





[Modified by JAKE, 7:37 PM 5/14/2004]

Re: L98 distributor gear, which one is correct? (JAKE)
 

Thanks for responding fellows.

The cam in my car is an L98 factory roller, which is indeed a steel cam.

Jake, you are right, this needs a melonized gear.

That is what my problem is, I don't know if it is indeed a melonized gear on it now.

Do you know how to help me tell the difference? What is the standard gear made of, if it is not a melonzed steel?

Don't want to purchase another gear for this, if it already has the appropriate gear. :)

Re: L98 distributor gear, which one is correct? (gene284)
 

No, steel BILLET. Steel billet camshaft cores are a different animal from what the factory installs; they are pretty expensive cores. When ordering an aftermarket camshaft you have to specify "steel billet core" in order to get it. The correct gear for a steel billet cam is bronze and gold in color. You can find them advertised in may of the catalogs as aluminized bronze, etc.

I don't know of any way for you to look at your gear and tell if it's melonized material. Your car is an 87' I suspect the melonize gears weren't available from the factory back then. I suspect GM cam out with it after many gear failures after they switched over to roller camshafts.

I don't know what year GM began installing melonized gears at the factory. A savvy Chevy parts guy can look it up and tell you. That's how I got mine.

The parts guy had ordered one for himself for his personal vehicle, then he learned that his car already had the melonized gear, so he just put the gear in "Parts" when it arrived. Normally it's a special order item, not normaly carried in stock. I just lucked out.

Visually, they look the same but the metal composition is different allowing for improved wear.

Jake


[Modified by JAKE, 2:44 AM 5/17/2004]