[Marco Tahtaras]

Originally Posted by Earle

If you're inclined to be one to defend the original fan and its continued use today, for whatever reasons, that's your choice. But the history of failures and the expense they've caused folks who've used them should be known by both the informed and the nubie-uninformed so they can make their own decision. I don't think that someone who voices that position should be accused of "spreading misinformation and B.S." We here can easily stick to the issues without denigrating the other person.

If you look back at what I wrote I've never suggested that ANYONE else run one. In fact in this same thread, two years ago this month, I wrote:

"With all that said I won't recommend anyone else run an original fan. I don't want to be called to task for the decisions of others and the resulting success or failure. It also won't hurt my feelings to have more fans to choose from on the swap meet tables!"

In recent days I've only argued against the supposition that the original design was a failure from day one and should have lasted forever. I've also argued in the past against those that insist an original fan should be disregarded in judging, most of whom admit they have no interest in ever showing a car however seem compelled to write the rules for those that do. There are some exceptions.

Originally Posted by Earle

Note - I hear the reports of others who mentioned different locations for initiation of the cracks. My own experience with each of seven original fans (while trying to find just ONE I could use - back when I was uninformed about them and was overly-obsessed with "originality") was that the crack initiated at the radius where the leading edge of the blade intersected the hub. Classic fatigue failures. Two of them developed cracks within a few hours of running AFTER being certified "crack-free" by professional magnaflux inspection.

Yep, I've felt like doing a writeup on the subject but just don't have the time. However since you brought it up I will add one point of interest (to me anyway). If you look carefully at an original fan you will note that the two layers are seam welded together around the perimeter. Some have clear pattern from the rollers. Look closely where the weld ends in the front near the hub. The machine was only able to get so close leaving a very short "open" area between the end of the weld and where the layers fold over the hub. This is the flex point where the two layers can move independently as they weaken. Every crack I've seen was at the end of the weld.

In my case, my fan has never been bulged from internal corrosion, the front face is flat, the blades are in line across the central axis, and although not tested I believe the pitch of both blades still match. Lastly, the "open" area has been tig welded closed to reduce the ability to flex at that point.

Will that all save my bacon? Only time will tell. I've run the engine at very high speeds a few times which I won't likely do again but so far, so good. Again, only time will tell. If it fails without me catching it in time then it's on me. As with most things in life, It's MY choice.