1986 civic 1.3l hondamatic not shifting
 

hi i have a 1986 honda civic dx with a 1.3l engine and a h3 hondamatic transmission. my car quit shifting into reverse then a few days later drive quit working .. no signs leading up to it and you can hear a light grinding when either o those gears are selected . this isnt the first time i have lost reverse .. i couple years back i lost it for an intire winter before it came back. i regularly do tranny oil changes so its not that. i dropped the oil and it wasnt burnt or anyrhing . if anyone knows something about h3 trannys it would be greatly appreciated . i have a shop manual for this car but it isnt a honda manual and doesnt talk about taking this tranny apart.. could really use some info on it as well . thanks