Help! 351 Windsor cam gear and distributor gear keep grindin off!

pimpenstang · 06-30-2007

This is the second build on my 351 Windsor. It is a carburated 5.8, with performer rpm heads, 1.7 rockers, msd distributor and ignition set up, comp cams extreme energy race cam,and blah blah blah...Anyway this is the second time I have ground the gear off my distributor and cam, this time around I did put all new cam, distributor, oil pump, eveything in it, less than 50 miles on motor after dyno break in and poof!!! It started popping and there she went again!! Is the guy who built it a moron or what is going on here??? Can someone please shed some light on this???Thanks

jgard07 · 06-30-2007

What type of cam have you been running, cast flat tappet or steel roller? And what type of distributor gear, iron or bronze? Sounds like you're having a problem with incompatable materials.

pimpenstang · 06-30-2007

I am running a hydrolic flat tappet cam and the distributor had a steel gear on it

The Greek · 07-05-2007

Can you see if there is a wear pattern on the distributor gear or is it too far gone? The wear pattern should be approximately centered on the gear. The dist. gear may have been installed on the dist. shaft in the wrong position.

There is also a conflict in the material this gear is made of. For a flat tappet cam the dist. gear should be made of either cast iron or bronze and not the hardened steel required for a roller cam. Some people also use the bronze gear on roller cams, but this isn't an issue here. ---Chuck

pimpenstang · 07-08-2007

I messed up we had a steel gear the first time this happened to the motor this time we had a cast iron gear on there.

We also called the msd tech line they claim that we MUST have too much oil pressure...well thats funny because we are running a complete stock oil pump and when we had it dyno tested all our oil pressure was perfect, not at all on the high side.
The way the gears look like they are hitting is that the angles between the gear on the cam and the distributor are different.

The Greek · 07-10-2007

From what you say the dist. gear is installed upside down. Is the roll pin that secures the dist. gear on top of the gear?

pimpenstang · 09-04-2007

the gear was installed properly. It was brand new. We figure we found the trouble though. We decided after all the bs to tear it apart ourselves pulled the timing chain cover off and the cam bolt fell out and had about three threads left on it.Beautiful, huh? Well we figure either mr builder boy didnt tighten it or he "forgot" to put lock tight on it. Needless to say he replaced everything out of his own pocket

The Greek · 09-06-2007

Thanks for the update. ---Chuck

TheBarberShop · 09-06-2007

Was gonna tell you to check cam end play for a "walking" cam before I saw your update!

Out of the bad distributor gear complaints I see i'd say 95% are caused by improper cam installations. Dist gears are much weaker than the cam gear -- and thank goodness, it's easier to pull a distributor! They make newer dist gears with silicon/bronze alloys, etc, but they're not a solution, more of a band-aid fix.

ralc · 09-23-2010

I had 2 problems with an MSD distributor.
The first problem was where the shaft is cut down below the gear for the oil pump drive. There was a .060" extended below the gear. I didn't know any better and pit it in. It bound up in the block and sheared the gear. I sent it back to MSD and they sent me a new distributor. This 1 had the bottom of the gear flush with the shaft cut. I put it in, snugged it down and started to set the timing when the distributor spun. I figured i just didn't have it tight enough but as I tried to tighten it down, it was not seating it against the block. Took it out and the bottom of the gear looked scraped. Pulled it out out and took it to an ignition shop. They put it in a bare block and showed me that the gear was installed too far down the shaft. from the distributor housing where it contacts the block to the bottom of the gear, it was 4.095. Said it should be 4.031-4.038. They also said there should be a minimum of .020" between the housing and the shim/collar. They also showed me a new MSD gear and a Ford Motorsport gear The MSD gear had the roll pin hole in the wrong location. They installed the Motorsport gear and it works great.