Injector o-ring erosion by oil pressure?

[JCart]

Note sure if this is the correct forum please move if needed.
Hey guys,
Just in the process of pulling out squirters and noticed all the driver's side ones have the top most o-ring (next the split ring) ruptured. Hope to get passenger side pulled tomorrow, shall see if they are the same.

Not sure of the history of these injectors and I think the PO said they where Swamps tranny savers so thinking 140/146? Been in the truck for at least 4.5 years (that's how long I've owned it) and I have put on 210,000 kms (135,000 miles), total of 465,000 kms on the clock, albeit again not sure how long they've been ran.

Gonna shoot them off to Tim at P.I.S., for 175/80, once I get the rest out and packaged up. So it looks to me that oil pressure has eroded the o-ring until it has ruptured at the split ring. Guessing this is not uncommon and wondering if anyone tried to stack two split rings and clock them such that oil pressure will not squeeze passed and erode the o-ring? Seem to recall this a few years ago when high pressure oil first came out (erosion of o-rings) but can't remember if anyone tried this?

What say yee....

Thanks jrc

 

[Chvyrkr]

The only other 3000 psi system I've worked with, had multiple split rings before the o-ring on servo feet. And yeah, you had to clock them or the o-ring would fail.

 

[lincolnlocker]

Post pics...


When I had my motor rebuilt, I had o rings like that and I think there was only 30k miles on those o rings... no clue what did it...


Do you by chance use STP oil treatment?

live life full throttle

 

[JCart]

Hopefully get the passenger bank out today.... No STP or any oil treatment. The last 2 years Mobile one synthetic 5w-40 with Donaldson ELF 7405 in stock location and ZGuard by pass filter. Prior to that Delo 400 and fleetgard filters. Run stanadyn and power service.

I'm not so concerned with the service life because I don't know the history of these injectors and it's kinda mute as Tim will be rebuilding to 175/80's. I guess I was more wondering if anyone doubled up on the split rings (perhaps thinner ones) to prevent o-ring erosion at the split ring joint. I would think by clocking thinner split rings this would minimize the issue.

Once I get the PB out I'll shoot some pix. The notion is to install fresh 175/80's and T500 then limper through till I can do a full rebuild.

jrc

 

[lincolnlocker]

Hopefully get the passenger bank out today.... No STP or any oil treatment. The last 2 years Mobile one synthetic 5w-40 with Donaldson ELF 7405 in stock location and ZGuard by pass filter. Prior to that Delo 400 and fleetgard filters. Run stanadyn and power service.

I'm not so concerned with the service life because I don't know the history of these injectors and it's kinda mute as Tim will be rebuilding to 175/80's. I guess I was more wondering if anyone doubled up on the split rings (perhaps thinner ones) to prevent o-ring erosion at the split ring joint. I would think by clocking thinner split rings this would minimize the issue.

Once I get the PB out I'll shoot some pix. The notion is to install fresh 175/80's and T500 then limper through till I can do a full rebuild.

jrc

Ok. Sounds good..

live life full throttle

 

[Patrick Feeley]

I also remember the postings regarding using 2 backup rings, but I can't remember the consensus opinion on going that route. I do know that the failures did seem to be right at the split of the backup ring. Cheers!

 

[Tom S]

My recollection is that had a lot to do with the brand of O-rings.

 

[09stroker]

How are the backup rings cut?

 

[Pstroke96]

that is a fairly common high mileage failure on these injectors, i dont think that adding another split ring would help since it is only moving the o ring down in the cup and not really spreading the load any better since there is still just the one ring contacting the o ring. also it might squeeze the o ring out of the groove farther than its supposed to be and put more strain on it than its supposed to have