455 rear main seal swap

[augydoggy455]

i thought i saw on here about being able to use a ford 2 piece rear main seal in stead of the rope seal but i cant find the post now ! can anyone help with maybe a p/n for this 2 piece seal im about to put the engine together soon !! thanks ,tony

[88hurstolds]

Funny you bring this up, I'm about to reseal my 403 and my brother is rebuilding his 455 for his 75 442. I belive it was a BBF rear main seal that was thicker and filled the gap better than the standard rope seal, most likely a 460 or a 427. I check the factory main size on each to confirm. Also, make sure you clock the seal about 5 to 10 degrees to stagger the seal about a 1/4" so there is continuity beyond the cap to block seal channel. basically one end of the seal going into the cap and the other into the block.

I had a fun time last may blowing a rear main seal or pan seal on a 455 and showering traffic behind me with oil and smoke. I was doing about 55 and it looked like a mosqito fogger going down the road with the oil burning up on the exhaust system. Good thing I caught it right away or it would have been disasterous

Another thing to check with the main seals when doing a factory rebuild is if the stock harmonic balancer is worn where it makes contact with the front seal on the timing cover. Sometimes you have to have a brass ring machined on otherwise it will leak like a seive...

[augydoggy455]

thanks for the info ,i'll try to get the specs and if i can get the correct one i'll post p/ns here for others

[gbodyfan]

460 ford seal is what your looking for

[augydoggy455]

got it ,put it in ,got engine together ,i'll post pics shortly

[88hurstolds]

Does anyone know what seal works best for 260-403?
I am looking to redo my 403 soon...

[gbodyfan]

You doin any work to the crank? I have heard a neoprene one works good but you have to polish were the seal goes on the crank. I have heard of people using a AMC 258 inline 6 or a 292 Ford