Taking off my primary injectors later today. The front one started leaking from the upper O-Ring, so both are going to be sent off for cleaning and flow testing.

I've contacted RC Enginnering and Witchunter and both use aftermarket Viton O-Rings to replace the OEM O-Rings (2 per injector).

Has anyone had bad results with these aftermarket o-rings with improper sealing causing fuel leaks ?? (Not including human error such as pinching the o-ring or not creating proper seal when re-seating at time of installment).

I'm just a little apprehensive about using aftermarket o-rings.

Thanks.

 

I would be more worried about mazda rubber parts as I and many others have had failures; vac hoses, oil pedistal o-rings, fuel lines, electrical insulation; these parts weren't spec to high enough temps. I'm much more confident when the provider can tell you the specs on their product.

A couple of months ago (2/05?) RC was using nitrile (n-buna) because their viton was on backorder. I believe the nitrile was a green o-ring. They'll work, but probably not as long as viton.

I order some hardware parts from mcmaster.com for this reason.

 

As long as they're a tight fit, the size is the same and you don't pinch them when you install them, a viton o-ring should outlast the stock unit. Lube them with oil before you install.

If you're concerned you could always pressure-test them before you put the car back together. Hook up the rail to the fuel line but don't bolt it down and ground the (I forget which) pin at the DIAG port to enable your fuel pump. Check for leaks.

 

i used some viton injector orings that i got at the auto parts store it fited snug and nice but it still leaked when i reinstalled it. i got new oem ones and booom, problem solved.

 

did you size them with a micrometer?

here's my scoff at oem; why are still selling the same vacuum hoses?

 

Both of those are excellent sources for O-rings. Aside from Mazda, I would trust no other source for them.

Dave

 

The cars are allready sold. They redesigned a new system for the newer 3rd gens to lessen the vaccum line mess. By the time any of us seriously need vacuum lines the car is out of warranty, so what would motivate them? Also, if you have to replace them (as a repair, not as a preventative measure) it will probably only be once anyway.

Danny, where in Laurel are you? I'm living here for another 2 weeks and moving to Woodbine.

 

West Laurel, do you know Oui over at Z auto?

 

When I sent my injectors out to RC engineering they said the size fo the o-rings on my injectors was not a standard size so it came back without them. I have seen posts of others who used something close and had leaks. I just went to Mazda to purchase OEM ones. I guess I did not want to have to pull my UIM and vacuum lines again just to save a few $ on o-rings.

 

I'm up North. And yeah, I donated a few parts to Oui when he was trying to ressurect his car from the engine fire.

(sorry for the off-topic content)