I thought changeover was earlier than that, somewhere during the last year or so of red motors. Always assumed it was at VB release. Possibly was done at blue motor release in 1978 Bedford trucks.

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Quote Originally Posted by Blocker View Post
Thanks - the one I bought was the 'early' model with the shorter neck. Only $50 so no biggie if I have to change it.
Later ones with longer bearing are twice the price, but worth if. If the one you have has a pressed metal fan-type impeller take it back. Get the one with a cast barrel type impeller.