New -12 Oil Lines Leaking

[StreetSnake]

I just installed -12 oil lines running to my remote oil filter and oil cooler and back. The larger lines (vs. -10) don't seem to be staying tight. I don't want to over torque these fittings. Does anyone have a suggestion on how to fix this.

[Rick Parker]

What type fittings did you use? Are they the type that use a "Cutter" that cuts into the end of the hose as the hose end is assembled? Some others use more of a compression type and sometimes leak within the individual hose end. I fought this with the -10 size hose ends I was originally using. It was very frustrating. I did not have trouble with the assemblies staying screwed together, they were leaking within the female assembly.

[StreetSnake]

Rich,
I'm not sure what type of fittings (they're red & blue, maybe aeroquip). If you would take a look at my gallery, I have a front end shot which shows my oil cooler. I thought about locktite or teflon tape but thats probally not a good idea either. Thanks for your help.

[Richard Hudgins]

StreetSanke,

Your fittings appear to be standard Aeroquip stuff.

They should should be drilled across the flats on the nuts for safety wire.

Just look high on the nut for the holes.

It is quite normal for the larger size fittings to not stay tight due to vibration etc.

That is why there are safety wire holes on the Mil spec Aeroquip stuff.

Helicopters proved the need for this bit of prevention in the 50's.

[vector1]

the aeroquip fittings are pretty tough stuff. if it is the flare portion that is leaking, make sure both mating surfaces are smooth with no grit or debris. i've had a couple prestart leaks because i didn't get them tight enough, just tightened them some more and it was cured. once the surfaces make contact i would guess another 1/8 to no more than 1/4 turn should seal well enough.

if it is the hose portion and the hose is inserted on the fitting the correct amount tighten some more also. otherwise take it apart and inspect and try it again.

i've put some pretty good torque on the hose portion and haven't damaged any fittings. i do use a lubricant on the threads sometimes to keep the aluminum from galling and ease installation.

[StreetSnake]

Thanks for the info, I'll work on her again today and let you know how it goes.

[427 S/O]

Victor! is correct, I marked the hose to make sure it was fully inserted, then clamp in vise with aluminum plates to protect finish, and torque pretty good. CAUTION---Don't forget to blow out the finished hose with lot's of air pressure.

[sdonnel]

Keep in mind that the 37 degree connection only seals on a hairline point of contact. Many people have falsely thought that the angled portions of the male and female halves compress together. Look for small nicks or dings on both the mating surfaces.

Scott D.
Aeroquip Training Specialist (previous life)