Glass Mechanix O rings

[shermfiddle]

Question: I've used GM O rings for years on my Power Vac Injector. These are the O rings that are located in the injector shaft. There are two that are installed and replaced on a regualar basis However, when I ordered more of them they won't work? They swell up and its very diffecult to engage the plunger shaft up and down. GM is working on the problem. If I buy O rings at Home Depot or other hardware stores they swell up too? There is a very important diffence in the O rings that GM sold and the ones you buy in the stores.

Thanks for your help.

[SeeClearly]

With the resins we are using, it is important to specify the material for the o-rings you are purchasing. It sounds as if GM either ordered their restock with the incorrect material specification, or someone in their supply chain screwed up on the material specification of what they supplied. The o-rings that are typical "over the counter" are not chemical resistant to the resins we all use. A more durable chemical resistant material should be used, and there are a few out there that are suitable. You will need to be careful though, as the more chemical resistant the materials, the higher the price. Feel free to PM me if you have any further questions. I hope this helps.