HF O-Ring Assortmant Questions

[red73mustang]

So Im rebuilding a cheap hydraulic floor jack because I hate to see stuff thrown away and I was in need of some replacement O-rings. Harbor Freight sells several very nice assortment kits that claim to be petroleum resistant, but are the Nitrile ones better suited for this environment than the standard rubber ones?

Regards, Chet

 

[k-os]

So Im rebuilding a cheap hydraulic floor jack because I have to see stuff thrown away and I was in need of some replacement O-rings. Harbor Freight sells several very nice assortment kits that claim to be petroleum resistant, but are the Nitrile ones better suited for this environment than the standard rubber ones?

Regards, Chet

I would guess that the "standard rubber ones" are nitrile. Buna-N (Nitrile) is the most common o-ring material.

 

[gte718p]

They sell a Viton kit as well that is definitely petroleum resistant. I have the Viton orings on the jack for my truck crane.

They work.
http://www.harborfreight.com/180-piece-viton-o-ring-kit-67525.html

 

[rlitman]

They sell a Viton kit as well that is definitely petroleum resistant. I have the Viton orings on the jack for my truck crane.

They work.
http://www.harborfreight.com/180-piece-viton-o-ring-kit-67525.html

+1 You want Viton for petroleum resistance.

But, I will say this. While I had great luck from a $7 buna-n o-ring kit from HF, I returned the $20 viton kit I bought, because most of the rings were misformed, and had flash on the mold lines. Total ****, and useless for sealing purposes.

 

[red73mustang]

I think the Buna-N type might be the right ones for my application:

Viton is far superior to Buna for high temperature applications. Viton seals provide an indefinite seal for temperatures up to 400°F, and for temperatures up to 600°F they offer an excellent seal for more than 48 hours. Buna on the other hand is only effective up to 250°F. However, Buna seals provide a low temperature sealing option with effective sealing down to temperatures of –22°F, while temperatures below 5°F render Viton seals ineffective as they become quite hard and inflexible.

 

[1982fxr]

imho those kits at hf are all ****. Never again for me

 

[WVBrady]

+1 You want Viton for petroleum resistance.

But, I will say this. While I had great luck from a $7 buna-n o-ring kit from HF, I returned the $20 viton kit I bought, because most of the rings were misformed, and had flash on the mold lines. Total ****, and useless for sealing purposes.

That's what about half of the ratings said.

 

[Fcvapor05]

Just order the exact o-rings you need from mcmaster. They're cheap.

 

[bwringer]

Just order the exact o-rings you need from mcmaster. They're cheap.

McMaster even has some decently priced assortments in Buna-N and Viton in standard and metric sizes.

As noted above, Buna-N is the correct material for oil and gasoline; Viton offers added heat resistance over Buna-N in places where that's needed, but it's harder and more expensive.

 

[G_P]

I'd just go buy individual O rings from a auto parts store or hardware store. I dont think I want to trust lifiting my car to a gasket made as cheap as humanly possible.

 

[TheEquineFencer]

Ask Hiball in his thread about the jack rebuild thread.

 

[rlitman]

McMaster even has some decently priced assortments in Buna-N and Viton in standard and metric sizes.



As noted above, Buna-N is the correct material for oil and gasoline; Viton offers added heat resistance over Buna-N in places where that's needed, but it's harder and more expensive.

No, and no.

Buna-n has ok, but not great petroleum resistance. Viton is fluorinated to give it more chemical resistance. HNBR is a hydrogenated form of buna-n that has higher heat resistance.

All three sorts of o-rings come in various hardnesses measured in the form of durometer.

 

[rlitman]

I'd just go buy individual O rings from a auto parts store or hardware store. I dont think I want to trust lifiting my car to a gasket made as cheap as humanly possible.

LOL. O-rings are ALL as cheaply made as possible. 99% of the retail price of an o-ring is in packaging. Buy one, spend $1. Buy 50, spend $2. Buy 500, spend $4. The hardware store isn't going to have anything better than an HF kit. OTOH, a parts counter MIGHT, but only if you're buying OEM parts, and that part isn't necessarily going to be "better", just the correct spec.

 

[Fcvapor05]

You live in New Jersey- if i were you I'd avoid Viton. It doesn't handle low temps as well, which means your jack might leak over the winter. If I lived in Texas I'd probably use viton and not look back.

 

[Mooky]

Find a Parker Store in your area. They'll have the individual O-Rings and can recommend the material. Enter zip code:
http://www.parker.com/portal/site/P...08743410VgnVCM10000014a71dacRCRD&vgnextfmt=EN

Page 187 has material compatibility ratings for various O-ring materials in hydraulic fluid
https://www.parker.com/literature/ORD 5700 Parker_O-Ring_Handbook.pdfI'm

 

[Contract_Pilot]

+1 for Parker. HF O-Rings are Junk!