Mr_Mudney 2 Report post Posted November 3, 2020 I’m in the process of rebuilding the carb on my 79 620. While taking apart the vacuum valve for the secondary two silver ball bearings fell out onto the garage floor..... I found one but lost the other, luckily the rebuild kit comes with replacements, but it does not show where they go in the exploded view and neither does the repair manual. Id appreciate some help in finding a home for these ball bearings, thanks! 1 Quote Share this post Link to post
datzenmike 37,336 Report post Posted November 3, 2020 I think there is only one BB in the bottom of the hole with a small spring on top of it. Do you have the spring? Maybe that is what you saw. The accelerator pump circuit uses two BBs as one way valves. Maybe that's what they are for. Usually the secondary vacuum diaphragm isn't dismantled. 1 Quote Share this post Link to post
bilzbobaggins 832 Report post Posted November 3, 2020 Thought I heard somone yell loudly from across the river. 1 Quote Share this post Link to post
Mr_Mudney 2 Report post Posted November 4, 2020 I opened it to check the condition of the diaphragm, I’ll take a look around for that small spring.... wish me luck XD And thanks for the feedback 1 Quote Share this post Link to post
420n620 541 Report post Posted November 4, 2020 (edited) https://www.carpartsmanual.com/datsun/pickup-1972-1979/engine-(l20b)/carburetor number 43 has a BB & number 13, piston has a BB When working on any carbs a towel should be placed under your work to catch your BB's or springs. AND never remove more then 1 screw at a time when working on the inside of a Hitachi ( main body ) , that way you can know where the piece came from. I also take pic's of the carb before I dismantle one for reference later if needed. good luck Edited November 4, 2020 by 420n620 1 Quote Share this post Link to post