i decided to replace the front seal in the gear drive while engine was apart.

i pressed out the idler shaft to remove idler gear to gain access to replacing the seal.
once seal was done , i'm having trouble getting the idler gear shaft back in.

using a large arbor press and after pressing back out a couple times to try chamfering leading edge and some light sanding and cleaning on shaft..... also aluminum bore is not scuffed or galled

i used some arp moly lube and still can't press it in without moderate to almost extreme force.

i get it to with in a 1/16" to 1/8"

it's almost like it was heated on first assembly

any suggestion's?

has anyone changed front seal on a big block Mopar Donovan gear Drive?

I've only messed with Milodon's. But
Is the shaft directional. in other words does it mic differently from one end to the other? There are two supporting bores?
Heating the bores would be good, especially with an arbor press. I have one and the only thong I've used it for was punching holes in gaskets and pressing pem nuts in sheet metal. I use my hydraulic press for these kind of jobs, press pins and the like.

Take some pics and post them