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68LAlonghorn · 04-01-2022, 02:39 AM

Hi Accelo,

So after a bunch of investigative work, it seems that my heads may not be the original ones. I checked the casting numbers on the heads (3998993 H3 2), and they seem to be from 72. Not sure if there is a difference between 68 and 72, but maybe they machined them before installing them? Still not too sure how to tell if they have been machined or not, would the positive seals fit if they were not?
Anyways, I've ordered the positive fel-pro seals and will try those out.

Here is a pic of the casting number on the head for your enjoyment!
Thanks so much for your help.

04-01-2022, 02:39 AM	#10
68LAlonghorn Registered User Join Date: Mar 2022 Location: Los Angeles, CA Posts: 27	Re: Valve seals Hi Accelo, So after a bunch of investigative work, it seems that my heads may not be the original ones. I checked the casting numbers on the heads (3998993 H3 2), and they seem to be from 72. Not sure if there is a difference between 68 and 72, but maybe they machined them before installing them? Still not too sure how to tell if they have been machined or not, would the positive seals fit if they were not? Anyways, I've ordered the positive fel-pro seals and will try those out. Here is a pic of the casting number on the head for your enjoyment! Thanks so much for your help. Attached Images