[gtofreek]

I'll take pics of the rest of the engine tomorrow. Yesterday I was tired afterwards[it was past 5PM]and covered in oil during disassembly to take any pics. Good news is crank and everything else looks great. Piston skirts don't look like they've even been run except for a couple very light scratches that are barely even noticeable. Piston pins are free and smooth moving. I still need to disassemble piston pins so I can clean and re-lube before reassembly. I might still have that MSD box at work. I have one I keep instruction for timing curves and extra parts in. I wrote Joe's name on his box when it came to me, so I'll know if the one at work was his or not. If so, I'll look at the origin code in the UPC code to see if it originated from China. Maybe that will shed some light on this. I have used at least a dozen of these distributors in other Pontiac builds and have never had an issue with one. We have used countless MSD distributors on many other brand builds also without any issues what-so-ever. So I was shocked to see this in such a short amount of time. It just sucks that Joe has been without the use of his car for a year because of this. Who would have ever guessed this was the cause. I think the reason why it sounded like it was coming from the torque converter area was because the noise coming from the distributor cap was hitting the firewall and traveling down the tranny tunnel and coming out around the tranny. Very deceiving. It was also loud under the hood and everywhere else too, so sound really travels with these deals. Just glad it didn't cause any other damage to the engine.

[mgarblik]

Originally Posted by gtofreek

I'll take pics of the rest of the engine tomorrow. Yesterday I was tired afterwards[it was past 5PM]and covered in oil during disassembly to take any pics. Good news is crank and everything else looks great. Piston skirts don't look like they've even been run except for a couple very light scratches that are barely even noticeable. Piston pins are free and smooth moving. I still need to disassemble piston pins so I can clean and re-lube before reassembly. I might still have that MSD box at work. I have one I keep instruction for timing curves and extra parts in. I wrote Joe's name on his box when it came to me, so I'll know if the one at work was his or not. If so, I'll look at the origin code in the UPC code to see if it originated from China. Maybe that will shed some light on this. I have used at least a dozen of these distributors in other Pontiac builds and have never had an issue with one. We have used countless MSD distributors on many other brand builds also without any issues what-so-ever. So I was shocked to see this in such a short amount of time. It just sucks that Joe has been without the use of his car for a year because of this. Who would have ever guessed this was the cause. I think the reason why it sounded like it was coming from the torque converter area was because the noise coming from the distributor cap was hitting the firewall and traveling down the tranny tunnel and coming out around the tranny. Very deceiving. It was also loud under the hood and everywhere else too, so sound really travels with these deals. Just glad it didn't cause any other damage to the engine.

I am glad you found an issue with a true witness mark on the part to verify. Just to clarify above, you mention the noise traveled to the firewall and down to the transmission/torque converter area. You don't mean there is anyway the distributor was contacting the firewall in any way at all do you? That could explain the whole situation. The worn bushing, only hearing it in the car and not on the dyno, the whole thing? Plenty of clearance in the rear around the distributor with the engine installed under all throttle conditions? Again, glad you have a handle on the issue, lots to be learned here.

[gtofreek]

One more thing. We were talking to the sales guy at Hylift/Johnson and he told use that there are counterfeit lifters coming here from China that are packaged in boxes that look exactly like theirs. He said the only way you can tell if they are theirs or not is to take them apart and look at the internals. That's why we buy them ONLY direct from Hylift/Johnson. Too easy to be fooled nowadays.

Remember, if the deal sounds too good to be true, it probably is!

[gtofreek]

Curious Joe, how much did Advanced Auto sell that distributor for?

[Cliff R]

Wear on the lower bushing should only happen in one place as it's got a helical cut gear on it and the cam is trying to push it away I one direction only.

Wear all the way around without any damage to the shaft tells me it was probably pretty darned loose or the wrong size right to start with as it really can't move around in a circle like that with the cam driving it, unless of course the shaft has a pretty good bend in it someplace.........Cliff

[gtofreek]

Originally Posted by Cliff R

Wear on the lower bushing should only happen in one place as it's got a helical cut gear on it and the cam is trying to push it away I one direction only.

Wear all the way around without any damage to the shaft tells me it was probably pretty darned loose or the wrong size right to start with as it really can't move around in a circle like that with the cam driving it, unless of course the shaft has a pretty good bend in it someplace.........Cliff

I totally disagree with that Cliff. I took this distributor apart when it was new and the bushing was not loose. You have to consider that when this is going bad, that distributor gear is being pushed all around once it gets loose. If the bushing is soft, it's going to wear anywhere the shaft makes contact with it. You can't tell me that the shaft is not dancing around once it starts getting loose. It's going to be trying to get away from the cam gear anyway it can. Especially once the reluctor starts hitting the magnetic pickup. That in itself will try jarring the shaft all over the place.

[gtofreek]

Originally Posted by Cliff R

Wear on the lower bushing should only happen in one place as it's got a helical cut gear on it and the cam is trying to push it away I one direction only.

Wear all the way around without any damage to the shaft tells me it was probably pretty darned loose or the wrong size right to start with as it really can't move around in a circle like that with the cam driving it, unless of course the shaft has a pretty good bend in it someplace.........Cliff

Also, when I rebuilt starters for a living, I saw on many occasions where the starter bushings wore out all the way around the shaft, and not just directly across from the ringgear. Once the bushing gets loose, the shaft just starts bouncing all over the place. According to your logic, those bushings would only be worn directly across from the ringgear. Just doesn't work that way.

[STEELCITYFIREBIRD]

Yeah I'm thinking if it has a bushing it may be one of the imposters that are/were going around.

[STEELCITYFIREBIRD]

If you go with a CD box....get one with a rev limiter!
A quick search produce this image as the first hit;
https://www.bing.com/images/search?v...x=0&ajaxhist=0

[Va68goat]

Formulajones,

The distributor was pulled several times but nobody caught it. I think because it was a new MSD distributor, nobody expected this.

[gtofreek]

Also, the vast majority of the wear is directly across from the cam gear. Cam is not bent, nor is the wear on the dizzy gear uneven, as stated earlier. I check and straighten, if needed, every cam I install in an engine. You'd be surprised at how many cams are bent to a certain degree right out of the box. Most are .002"-.005" bent, but I have seen as bad as .025", which was unstraightenable, and sent back to manufacturer. I bet most builders never check a cam for straightness, and just assume it is straight. We check, straighten if needed, and polish every cam we use, whether we bought it or the customer did. Not very often are they perfectly straight.

[STEELCITYFIREBIRD]

The Pro Billets I set up this weekend had a bearing at the top. I put gear lube in the hole in the housing before I install them.HTH

[gtofreek]

Joe, in your pics, can you zoom in to see the UPC code. You can tell country of origin from that.

[1968GTO421]

This is fascinating info to consider. Joe, are you having Paul replace the distributor with something else, or is Paul rebuilding the existing "dud" for you? Thanks.

[dataway]

Hey ... my sound file analysis was vindicated I knew it was something camshaft driven since it was very clearly half engine speed. But ... a distributor bushing would not have been my guess. I mean how often do you see that happen.

[JSPONT]

Originally Posted by dataway

Hey ... my sound file analysis was vindicated I knew it was something camshaft driven since it was very clearly half engine speed. But ... a distributor bushing would not have been my guess. I mean how often do you see that happen.

Yes sir, good call!!

[grivera]

Joe - If you determine it's an authentic MSD dizzy, I think a new bushing may be best course of action - imagine if you bought a new dizzy and it has the same crap bearing.

Paul - how do the main/rod bearings look? Did any metal from the dizzy bearing make it to them?

[gtofreek]

Originally Posted by grivera

Joe - If you determine it's an authentic MSD dizzy, I think a new bushing may be best course of action - imagine if you bought a new dizzy and it has the same crap bearing.

Paul - how do the main/rod bearings look? Did any metal from the dizzy bearing make it to them?

The bearings and crank had no scratches at all.

[gtofreek]

Hey Mike, what I meant was the noise was traveling down the tranny tunnel. Nothing hitting the firewall physically.

[mgarblik]

I was pretty sure that's what you meant. Wishful thinking I guess. That would have explained allot. Are you going to run it before shipping it back? If you have to buy time, I just bet this group following this thread and the way you have handled it would help pay for the time. Let us know.