i have and old Briggs made in the 70's i got it to run but its compression is very low. it will fire right up because i found an electronic ign coil from a newer mower that had blown up so the ign is great but as soon as i put it under load it slows way down and it spins over super easy so I am thinking the compression is way down. it is a 2.5 hp. how much would it be to rering this mower? i have had it in the family for years, used to be grandpas and it was in the shed when i got the house. i mowed with it when i was a kid. so it has sentimental value as well as being cheap to run. It would be nice to get it running right for all the trim work.