same mistake on 2 tecumseh carbs

[38racing]

I've made a tow behind mower unit using 2 old 6 hp tecumseh push mower engines last summer to use at our large church property . Near the end of season one kept stopping due to fuel blockage crap in carb bowl. I took off carb and take apart to clean up everything. I found that the centre plastic nozzle didn't look right . I found bottom piece broke off so I replaced it. When assembling I found bowl nut didn't have room to tighten. I verified that bowl nut was correct part. Then I realized that the top o-ring was still in the tower making the nozzle lower. I then realized that my problem was that when I previously serviced the engine for use I had left the old o-ring in place and then added a new one. I must have not noticed the issue with the bowl nut and tightened it in until it broke the nozzle, creating the crap along with now out of place lower o-ring. So today it's running fine but it's twin on the other side seems to be flooding out. I brought carb home to service and found I had made the exact same mistake . Bottom of nozzle is broke. I've pulled a lot of theses tec nozzles but go figure that I messed up both of these. Anyway I was checking my supply of o-rings and I found that tecumseh has two part numbers,632547 and 630740. I'm wondering why. Supplier are selling one ring to replace both. My supplier is .50 cdn per o-ring. Here's some craziness
https://www.amazon.ca/Genuine-OEM-Tecum ... B008TSXJEY

[38racing]

I couldn't locate the o-rings from my supplier but I had 2 oem 630740. The id on them was too big for the nozzle. I just used 2 from my o ring kit and they were snug on nozzle and in the tower.
The carb had manufacturer number 1916 but it''s not on the list at outdoorpowerinfo.

[KE4AVB]

I have three different o-rings sizes listed here.

• 3/32 x 7/32 (Dash 005) (actual OD is .241)
• .114 x .241 x .070
• .125 x .250 x .070 (Dash 006)(actual OD is .254)

Both of the Dash numbers are available through Grainger here. They are about .05 USD each but you must order a pack of 100.