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souzape
September 14th, 2004, 05:44 AM
Looking for anyone else who may have had distributor problems with a 351C. My Southern Automtive Cleveland broke last evening showing all the symptoms of a failed roll pin in the distributor shaft. I say this with some certainty because I got the same failure last year. I'm running the electronic distributor with a Duraspark control box. Would like to keep the Duraspark but wondering if there might be a better aftermarket distributor body which might not exhibit this apparent weakness. The first time it failed was at about 1200 miles and I have about 3200 miles on it now. Need better reliability than that.

Phil Souza

eliminator
September 14th, 2004, 07:07 AM
Phil,

I would strongly recommend a MSD or Mallory Dist. These units are so much better than the stock stuff. The MSD I beleive is compatiable with the Duraspark Box. Call MSD Tech people.
They both have nice bearings instead of the bushings in the older units. You can get them at a good price from JEGS or Summit Racing. The mechanical advances are much better too and adjustable.

Rick
#4279405

pgermond
September 14th, 2004, 07:14 AM
Phil,

Bummer [xx(]

I'm planning on doing as Eliminator recommends - MSD Pro Billet.

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

KrAzEcJ
September 14th, 2004, 07:25 AM
quote:Originally posted by eliminator

Phil,

I would strongly recommend a MSD or Mallory Dist. These units are so much better than the stock stuff. The MSD I beleive is compatiable with the Duraspark Box. Call MSD Tech people.
They both have nice bearings instead of the bushings in the older units. You can get them at a good price from JEGS or Summit Racing. The mechanical advances are much better too and adjustable.

Rick
#4279405

Yep but which spring Rick? The pretty silver one or the gold one, maybe the black one? LOL J/K
The reason I say this is that I just replaced my Mallory vacume advance with the MSD Pro Billet and got it yesterday and was looking at all the pretty springs.


Unique 4279459

souzape
September 14th, 2004, 07:26 AM
Thanks for the input ... I've got a query into MSD now.

Phil S

clayfoushee
September 14th, 2004, 08:46 AM
Yeah, I'm holding my breath too, until I get around to it.

Clay

'98 Unique #9299, 427FE side oiler (452.1-stroker), top-loader (close), 3.31 rear

Annapolis, MD

ralphscott
September 14th, 2004, 01:00 PM
You can go to AutoZone get an assorted roll pin collection and insert a smaller roll pin inside a larger one so you have a roll pin within a pin. Trim to fit, of course. It will reduce the effect of the oil pump on roll pin compression and failure. regardless of the distributor you use if it has a slip-on gear.

Ralph

Jim Harding
September 14th, 2004, 02:33 PM
Just off the top of my head, I think the problem is more than just related to the distributor. These OEM dizzys last for tens of thousands of miles. Too tight clearances can cause some binding of the shaft, but this issue will be there with whatever dizzy you stick in there.... probably more so! And if something is binding enough to shear off the pin, I'd like to know that before I just stuck another one in there.


Jim Harding
La Plata, Maryland

1982 #3004
http://www.capitalareacobraclub.com/albums/album26/1aLeftside.thumb.jpg

Brent
September 14th, 2004, 02:49 PM
If you run a heavy weight oil and a high volume oil pump the roll pin takes ALOT of stress. These motors rev fast and move alot of oil very quickly.



Brent
4279401
Candy Apple Red/White
402 FE/Toploader/3.54

Poorboy
September 14th, 2004, 03:00 PM
I think the failure of the distributor drive gear pin is more related to the oil pump than any thing else. The cam drives the distributor which in turn drives the oil pump. You start increasing the oil pump volume and or pressure you increase the load on the pin. Changing the distributor will have very little or no effect pin load. Increasing the the pin dia. would be a better idea.

souzape
September 14th, 2004, 03:02 PM
For what it's worth I spoke with Bill Parham today since this is a repeat problem with the engine. Southern Automotive recommends either 50W or 20W50 Valvoline in their engine so I have been running 20W50. The engine also has a high volume oil pump. Bill recommend drilling the pin passage and replacing the stock roll pin with a larger one. He says that's how he sets up his race engines. Since the distributor was calibrated to the engine I have elected to try this route as opposed to buying a new unit for now. Local machine shop verified that broken distributor shaft/gear/pin problems are not uncommon with Fords set up like mine. As of the present, none of the aftermarket folks have responded to my query but if they do I will file the answers away in case the larger pin fix doesn't work. Thanks to all for your thoughts.

Phil Souza

clayfoushee
September 14th, 2004, 04:40 PM
Thanks, Phil S, confirms what I've been reading too. I'm running the same oil, and I've never known whether to be happy or scared that my oil pressure is always 75-80psi above 3K either hot or cold. Cold idle pressure is in that range too. The lowest I ever see it hot is 40psi.

Clay

'98 Unique #9299, 427FE side oiler (452.1-stroker), top-loader (close), 3.31 rear

Annapolis, MD

pgermond
September 14th, 2004, 07:06 PM
Phil S,

Keep us posted. I'm using VR-1 20W50, w/constant oil pressure of 50-70, and this issue is always in the back of my mind.

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

ralphscott
September 15th, 2004, 06:04 AM
Jim, one of the guys at Pigeon Forge had the bushing problem you described and it accelerated the deterioration of the bronze gear to the point he had to have his sons bring up a new distributor 'cause the car quit running. Will and Joan drive their little 302 everywhere. So not only the roll pin fix is important but the binding of the shaft can cause gear failure where the teeth break off the gear before the roll pin fails as we saw at Pigeon Forge.

Ralph

KrAzEcJ
September 15th, 2004, 07:24 AM
Guys heres some good info to read also http://www.cobralads.com/butcher63.html

Unique 4279459

pgermond
September 15th, 2004, 07:36 AM
Cj,

That's good stuff!!!

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

ralphscott
September 15th, 2004, 08:26 AM
I gather from what he is saying that when we clamp the distributor shaft down with the distributor clamp the downward pressure of the clamp forces the base of the gear tightly against the engine boss restricting the shaft from freely rotating hence gear tooth failure. I don't know what the interior of the distributor hole/engine boss looks like, but it would sem to me that you should be able to see scuffing of either the engine boss or the bottom of the gear if you have this problem. Even teeth wear is important so a spacer at the top of the engine where the distributor goes into the engine may in fact worsen the problem if there is not one to begin with. So that being said did Ford engineers goof-up? I ask that 'cause the frequency of Ford distribuors having gear tooth failure seems too high. Like the one this last weekend -- Ford distributor that came with the 302 engine I could see it with after market distributors (though some are much better engineered).

Ralph

KrAzEcJ
September 15th, 2004, 09:15 AM
Ralph when you say Ford dristributor that came with the 302 I'm a little confused. Was it a crate motor? These reason I ask is that I'm sure his motor doesnt have the original cam in it does it?. If it does I see your point. For those of us who are building our engines its a easy to check by installing the cam in the bare block and droping in the distributor and hand rotating the cam to check against any binding. I have never heard of a problem with a dist. shaft binding against the engine boss only that the dist is a little short and not fully engaging the cam gear or to deep and causing the dist. gear to bind due to alignment with the cam gear.

Unique 4279459

souzape
September 15th, 2004, 09:58 AM
My specific problem has not been gear tooth wear (I went back and looked at the gear and don't see any abnormal scuffing or visible wear patterns) but rather that the roll pin holding the gear to the distributor shaft is shearing. I really do suspect this problem is a result of the high volume pump and heavier weight oil. Grandma's Granada was never intended to run 80 psi. The gear tooth problem is most likely worth archiving for future reference. I would wonder if the discussion about gear teeth is specifically about Windsors or Fords in general too. Good write up about troubleshooting.

Phil Souza

ralphscott
September 15th, 2004, 10:35 AM
CJ My understanding was the engine came out of a Mustang, not modified just dropped in. The distributor was hard to turn when removed from the engine so my first presumption was that the bushing in the distributor shaft was galled and that caused the ultimate problem. Now I would like to se that distributor again and he bottom of the gear.

Phil, a roll pin within a roll pin as I noted earlier may solve your problem. It is a racer's trick, though I am not a racer. I have not snapped mine yet and I have about 70 psi at 60 mph 45-50 at idle at operating temp I also run 20/50 synthetic Castrol. Thanks for the comment I have to paraphrase some of these long winded write-ups to make sense of them.

Ralph