Please help determing what material oring to use.

[wantabeengineer]

Hello Engineers,
I am working on ford powerstroke heui injectors. Im needing to figure out what material orings to use for the internal orings. There are 3 of them. One is static, sees 400-2800 pounds of pressure and is in contact with motor oil only. Another is static, sees 400-2800 pounds of pressure and is in contact with oil and diesel. The other is dynamic reciprocating, sees 400-2800 pounds of pressure, it's used on the intesifier piston and is subject to motor oil and diesel. I can only get a new injector through ford and the injector rebuilders will not sell me orings because so many people have messed up their injectors. I asked a seller from china what the orings they were selling for internal heui were made from and they told me FKM, FPM but i dont know if what they are selling is proper. Please help!!!???
THANKS!!!!!!!!!!!!!!

 

[monkeydog]

wantabeengineer,

If you wantabeengineer, the first thing you need to do is perform your own research on your design solution. 30 years ago, I would have gone to an experienced engineer and asked the same question. The engineer would have pointed to the Parker Handbook and said "the answer is in there." "If you need help understanding it, let me know"

http://www.parker.com/portal/site/P...CRD&vgnextfmt=EN&Keyword=O-RINGS&wtky=O-RINGS

If you need help understanding it let me know.

 

[btrueblood]

...and the proper reply is a thank-you, and maybe a star, for monkeydog.

 

[1gibson]

You're comfortable guessing at the durometer for that dynamic o-ring?


If so many people have messed up their injectors, what makes you different? How did they mess them up? Not saying you can't handle it, just making the comment.

 

[wantabeengineer]

Hello,
First I want to thank you all for helping me with my post. (Monkeydong) Although wantabeengineer may be misleading I intended it to send the message that I am not an engineer, right off the bat. I don't actualy want to be one. I have been in that manual already but now I'm a little more confident so I will look again. Thank you for offering to help me if I need help understanding it. (Btrueblood) Thank you, I will take your advice. (1 gibson) I'm not comfortable guessing the durometer, especially for the dynamic one. I was hoping someone that knows a lot would tell me what type oring should be used. What makes me different from the average do it yourselfer is that I have been a mechanic for 20 years. I don't know what they mess up on them. Thank you for responding to my post.

 

[Hidromar]

Hello!

The question here, mainly, is not about the o-ring material, but mostly about housing.

You can use a "poor" material with a very good housing, and the o-ring will work OK

In case of doubts, try to use a NBR 90 Shore A O-Ring. In case of high temperature, use FKM/FPM, but aways being 90 Shore.

NBR will work nice on a diesel environment.

The problem about pressure is extrusion, and this one is made by a poor housing design.

http://www.hidromar.es

 

[monkeydog]

wannabe,
Semi-clever twist on my moniker.
Almost redflag worthy.