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brougth this 76 bus for my son has 73 1700 with 5or 6 rib trans has bad oil blow by out the fill cap will not pull itself up any kind of a grade tuned up new carb new coil runs good just no power on the grades

The gearing is wrong for the engine. By checking all the basics leak down test, compression test, valve adjustment, timing, fuel mixture you might find a tiny bit of power but not enough to climb hills. It is the same as the guy with a Baja who puts 31 " or taller tires on a stock bug engine first and second gear seem decent, third is iffy and fourth almost useless.

do a leak down test, it's probably blowing past the rings pressurizing the crank case, which is blowing out the oil, and the lack of compression causing a lack in power, is the reason why it won't go up hill

Also carry out a hot compression test, check the breathers are clear, probably blow by.

A 1700 T4 (in decent condition) works fine on a 6 rib, even pushing a Bus, BTDT.
There's much than the obvious ~100cc displacement between a 1.7L T4 and a 1600DP going on.

Your jugs and/or rings are probably worn out, do compression/leakdown testing as suggested.
The bottom end may be in great shape, the rods can be pulled to inspect the bearings once the pistons are off.
If the rod bearings are good, and the cam/lifters don't have any obvious issues, I'd stop digging, unless you plan on a full rebuild.
Even in that case I'd treat the main bearings carefully as the replacments are expensive and may not fit as well.
The heads should probably be looked at carefully by a t4 specialist.