Stripped Dizzy Gear, Different Pitch? Pics Inside

[Mustang78]

I bought this reman distributor not more than 200 miles ago, i asked for a dist. for an 81' crown Vic 351w since they "should" all be the same. I gave them my old one as a core(i ran that one at leask 1,200 miles with no wear to the gear, replaced because the 8 blades inside were hitting the magnet) Anyway i was driving tonight it misfired, sputtered then quit. I cranked it over with the dist. cap off and the rotor would turn 3/4 of a revolution then stop until i helped it turn..So i pulled it out in the parking lot and this is what i fine, unfortunately a gear from a 302 wont fit so i was SOL and had to be towed home(Thanks jeff-7T9cobra). Do parts stores sell just this gear? i am running a flat tappet setup FYI so i still need a cast iron gear, it looks like the pitch was wrong between the 2 gears, right?

~Mark~

 

[Mustang78]

the pictures suck but all the teeth have a very sharp edge(only worn on one side), and 5-6 are completely broken off...they are about 1/16" thick at the base and ready to break off also..

 

[hungrymonkey]

what cam are you running in the motor? and you should be able to buy just the gear.

 

[vristang]

You can replace the gear only...
I know MSD carries all of the geas you may need.
Look through Summit and Jegs and you should find some options.


However,
Most likely the cam gear is in similar condition...
check the cam grear too.


There are several things that can cause wear like this. Most of which will require replacing the parts to fix... like the cam,springs, etc.
I don't know how to evaluate what may have caused your wear problem.

I had a similar issue, and the advice I have recieved says the problem was due to cam selection. I was using a reduced base circle cam.
When I pulled the motor apart I also found that I had been floating the valves.
All of these things will add to quick destruction of the valve train...

Where did you get your cam/lifter/spring/pushrod setup?
I would be going back to them for advice (depending on who they are)...


jason

 

[Mustang78]

the problem started when i put in the reman distributor... the old dizzy was ion there for 1,200+ miles with no unusual wear, this one lasted 200 miles if that. I bought a new gear today and i'm about to install it, hopefully this one is made of harder steel, who knows..i dont want to tear everything apart unless i have to, the magnetic drain plug should get the chunks, and i'll change the oil if everything check out fine, i'll also check for wear after a couple hours

~Mark~

 

[iapexl8r]

dude before you install your gear you need to make sure it is the right one. what i mean is: if you have a roller cam (most rollers and a few retro rollers) require a steel dist gear. if you have a hyd flat tappet cam the dist gear needs to made of iron. these are not interchangable! It sounds to me like you have a roller cam (i base my guess on hte fact that the dist gears lost although definatly inspect the cam gear to besure) If you still have the old dist you will notice the dist gear has a machined apperance on the area above the gear. the one in the pic should have a cast appearing area above the gear verifing that it is indeed iron.

you can also try to scratch the area above the gear with a nail. the iron gear will sctatch the steel gear will not.
good luck

 

[Mustang78]

Do parts stores sell just this gear? i am running a flat tappet setup FYI so i still need a cast iron gear

I am using a cast iron gear the replacement seems to work perfect and the dizzy seated the first try, came from the HELP section of the local parts store

~Mark~

 

[Yellowpnoy]

I had problems with a distributor in my car, i had an MSD dizzy in it and they tried to diagnose the problem with a stock distributor out of a 351 with high miles on it. The gear on the MSD was fine, but it chewed the gear on the old distributor in about 15 miles. The only difference between the two, the stock one had a lot of shaft play (up and down). I took the stock one out and replaced it with a new MSD (not the one i took out), and the gear on the MSD was fine when i pulled it about 150 miles later. Make sure that there is not a lot if up and down play in your dizzy shaft, as that will cause the gears to bind and wear prematurely.

Anthony
427w

 

[88mouse]

What is the firing order on the motor. I had the same probable, the part store kept giving me a cast gear and i need the steel one. Some one may have swap out the cam for a steel cam.

 

[Mustang78]

i am using the 302 firing order, it was the only one available with my rebuild kit...does anyone know what the distributor shaft end play should be? this one moves almost 1/4" up and down..

~Mark~

 

[88mouse]

All dizzy move like that. Witch firing order is it? There are two different ones.

non H.O: 15426378
Non h.o needs to use a cast gear. A steel gear will wear out the cam.

H.O: 13726548
H.O's needs to use a steel gear. A cast gear will wear out like yours has done.

 

[Mustang78]

well thats what i meant, it's the regular 302..15426278 man i really need to memorize those numbers! Anyway i read that when the distributor is installed and clamped, the shaft should move up and down about .010", right? i'll grab it with pliers with the rotor off and see if it moves at all, i have a feeling it wont..

~Mark~

 

[PUNISHER RACING]

It looks to me like you had a cast gear on a steel cam, what cam you running?

 

[Mustang78]

I am running this cam: http://northernautoparts.com/ProductModelDetail.cfm?ProductModelId=1696

my old distributor was cast and it didnt wear at all...i have about 100 miles on the new gear and i need to check it for wear soon also. There is a weird knocking sound at a certain RPM then it goes away, sometimes while cruising it does it too..it's hard to explain but isn't spark knock or bad bearings, and i really doubt one or more valves are whacking the pistons..it almost sounds like a rocker arm is tapping the valve cover, but most definately isn't(it did the same knock with the old valve covres and the new tall ones) I am at a loss..if there was a local pro of some kind around here it's the kinda sound you have to investigate yourself

~Mark~

 

[vristang]

I am running this cam: http://northernautoparts.com/ProductModelDetail.cfm?ProductModelId=1696

my old distributor was cast and it didnt wear at all...i have about 100 miles on the new gear and i need to check it for wear soon also. There is a weird knocking sound at a certain RPM then it goes away, sometimes while cruising it does it too..it's hard to explain but isn't spark knock or bad bearings, and i really doubt one or more valves are whacking the pistons..it almost sounds like a rocker arm is tapping the valve cover, but most definately isn't(it did the same knock with the old valve covres and the new tall ones) I am at a loss..if there was a local pro of some kind around here it's the kinda sound you have to investigate yourself

~Mark~

If you're serious about finding a shop...
Jim Greens in Lynnwood
Brad's Custom Auto in Seattle
I can get phone numbers if you pm me... I'd rather not post them up...


I doubt they would be cheap, but they are the only places I would trust with a performance build.
Brads works almost exclusively with Corvettes and Mustangs, so I would try there first.


jason