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JeepSnake
November 30th, 2004, 07:35 PM
Hey y'all!

This is my first time posting, so I hope that I get everything correct on how this works. For those of you I haven't met in person, I'm Will & Joan Butterworth's older son and sometimes emergency mechanic. This brings me to the trouble we've been encountering with their smallblock; I think that Ralph mentioned in another topic what happened, but I'll go into more detail here.

Engine in Mom & Dad's 427 is a 5.0 liter from a 1992 Mustang. The engine had 16,000 miles on it when we removed it from the donor. The long block is completely stock '92 HO - no cam change, no oil pump change, nothing in the heads or bottom end. We simply removed the fuel injection unit and replaced it with an Edelbrock Performer intake and carb. For the ignition, we used a stock-rebuilt Ford Duraspark II system bought from Autozone. The only modification we made to it was replacing the iron gear with a bronze one to protect the cam gear. This combination worked smoothly for 2 years (about 6000 miles).

Then, in September, on the annual Pigeon Forge trip, the distributor seized up and sheared the bronze gear teeth. I mean the distributor shaft literally seized in the distributor housing so tightly that we could barely turn it by hand upon removal from the engine. So, we yanked an identical Duraspark distributor from my brother's '66 Mustang (again, probably 6,000 miles on this distributor), stuck a new bronze gear on it, and installed it in the Cobra to get it running again. Of course, our assumption at the time regarding the seized distributor was "a cheap rebuild."

Fast forward to Thanksgiving. Dad has been looking at an MSD for some time, so he removed the second Duraspark II unit and installed a new billet MSD; we had Dutton's press the proper steel gear on the distributor. The swap went great, and the MSD fired up like a champ. HOWEVER - upon inspection of the second Duraspark, we found the distributor shaft well on it's way to seizing in the housing. It still turns, but is very, very tight.

So, now the question is this: is there a problem in the engine causing the distributors to seize? I've heard of HV oil pumps, etc. causing failure of the gear, roll pin, etc. - but nowhere have I found anything mentioning what might cause the dist. shaft to seize in the housing! Could improper installation of the bronze gears have resulted in an undue load on the distributor shaft bushings? We'd blame it on a cheap rebuild again, but we've run up probably 70,000 miles on vehicles with parts-store distributors without any problems.

Does anyone have any insight into this? Of course, our worry now is that we have an engine problem that could destroy the brand new MSD!

Thanks in advance for any help you can give us!
ZACH

Zach Butterworth
Apple Mt. Cobra Pit Crew
(Mom & Dad's 427)

KrAzEcJ
November 30th, 2004, 07:54 PM
Hello Zach, I posted this a little while back and it is very informative. Take a look to see if this gives you any ideas on solving the problem. http://www.cobralads.com/butcher63.html

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will butterworth
December 1st, 2004, 07:15 AM
yea cj and zach it does. Zach look closely at bottom of gears in thumbnails-see thin ridge worn off and clashing of underside metal-Cyrus 302 gear has shown exc. wear also ,in mustang, so what say we run new msd for a while, pull it and review very carefully under gooood light, i suspecioned some anomaly as this article points to. Also, some bowtie boys have told me that ford has very little oiling going on on the dist. cam gear resulting in failure.We can get a gov. grant to set up a laboratory to study this phenomenon.Will-alabama

KrAzEcJ
December 1st, 2004, 08:18 AM
Just for grins guys see if there is any shaft length or bottom of gear to end of shaft differences between the two distributors for curosity sake. I havent had any problem with needing to do any shimming on the 385 series motors but after reading so many folks were having problems with the small blocks I checked mine to be sure and the cam gear and the distributor gear were almost pefectly meshed with neither up to high or to low in relationship to each other.

Unique 4279459