x2
Could be the diaphram, could be the check valves. Only way to know is to open it up.
Do a little polishing on the back side where it won't show & see what happens.
How's the output of the T98 configured? IIRC the M715 used a divorced xfer case & does not adapt well/easily to an attached case.
Actually if you split the felt into two you can get one of the halves in with the two FM seals. Not sure if it actually helps anything but what...
If you go the double seal route again (much recommended) these are the ones you want- [ATTACH] How's the surface of the output yoke? if it's at...
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