my oil cap on my 88 turbo wagon seems to be leaking , so i switched it with another 1 , you can see oil leaking down the neck , can the seal underneith the cap go bad ? , what i did was back it off alittle and is tighter now, or is there something else causing it, ? oil level is good, and fresh,

Every soob I have had, or worked on, I had to back the oil cap off a bit to snug it up. I never looked into it further than that.

If you remove the cap while it's running, you will notice an air pulse from the crankcase pressures. Essentially from the pistons pumping the air around. The oil you see coming down the tube was originally vapor that condensates at the top of the tube. You may have excessive blow by from worn rings creating more air/oil vapor movement. Or maybe just a cloggged or just dirty PCV. Does the engine use a lot of oil??

maybe 1/2 qt every 3000 miles, it drips it from the rear main

1 qt. every 3000 is still within spec. according to Subaru. I would say 1/2 qt is fine for any 20 yr old car.

 

GD

Turbo's have more pressure in the system, it will cause oil to leak out the filler tube if the cap isnt tight. I've taken the ears on the under side of the cap and squeezed them in a little with pliers to make a tighter seal. The ideal fix is a new cap tho, should be able to get one from the Dealer. Dont the rebuild kits come with a new seal? I believe I've seen one before.

thanks,

I have fixed a few with large o-rings. Takes a few experiments. Turn past friction, then back to seal.

after afew days of a tighter cap , i have noticed less oil leaking , here i was thinking it was a power steering fluid leaking around the fitting and dripping onto the spash plate , i should have noticed it sooner

Every soob I have had, or worked on, I had to back the oil cap off a bit to snug it up.

 

all three of ours are like this...if fully closed (to the stops) the cap is loose, if backed off a little it snugs right up.

Kinda surprising that Subaru didn't come out with a fix for that since it probably affects emissions. My loyale does the same and I back it off like the others who have posted here.

I wonder if the loose fit is part of the PCV system? Supplies a little fresh air to the crankcase, and perhaps helps stop oily scudge build up in the filler neck?

 

Is there a breather elsewhere in the system? If not, where does the crankcase air come from?

 

I sealed mine. Maybe it is not a good idea?

i cleaned the tps , and yes it was dirty, but i think i did something else to cause this and not the oil cap , but it could be ,

Every soob I have had, or worked on, I had to back the oil cap off a bit to snug it up. I never looked into it further than that.

+1

 

So are you or are you not leaking from your breathers?

They are supposed to seal down tight. If it does not, or you have to "back it off" then you need a new rubber gasket inside the cap or the tabs need adjusting.

 

GD

I wonder if the loose fit is part of the PCV system? Supplies a little fresh air to the crankcase, and perhaps helps stop oily scudge build up in the filler neck?

 

Is there a breather elsewhere in the system? If not, where does the crankcase air come from?

 

I sealed mine. Maybe it is not a good idea?

They are supposed to seal. The crankcase gets fresh air from the intake.

They are supposed to seal down tight. If it does not, or you have to "back it off" then you need a new rubber gasket inside the cap or the tabs need adjusting.

 

GD

 

NOBODY ever touches on that... the cap is held in place, not by threads, but by two metal tabs on the underside. Bending those tabs "up" towards the rubber seal, tightens the fit of the oil cap. I discovered this right after I did my timing belts, as I was checking the oil before I started her for the first time.

NOBODY ever touches on that...

 

I have seen it (occasionally) addressed..... I'll tell you what NOBODY touches on - the o-ring for the dip-stick. If you have an air leak into the crank-case the FI computer will judge the mixture incorrectly (it creates a vacuum leak). The engine needs to be TIGHT, and the oil cap, and to a lesser (but by no means insignificant) extent the dip-stick o-ring are the two weakest links in sealing it.

 

GD

I have seen it (occasionally) addressed..... I'll tell you what NOBODY touches on - the o-ring for the dip-stick. If you have an air leak into the crank-case the FI computer will judge the mixture incorrectly (it creates a vacuum leak). The engine needs to be TIGHT, and the oil cap, and to a lesser (but by no means insignificant) extent the dip-stick o-ring are the two weakest links in sealing it.

 

GD

 

glad I put it that way, and thanks for the tip

I have seen it (occasionally) addressed..... I'll tell you what NOBODY touches on - the o-ring for the dip-stick. If you have an air leak into the crank-case the FI computer will judge the mixture incorrectly (it creates a vacuum leak). The engine needs to be TIGHT, and the oil cap, and to a lesser (but by no means insignificant) extent the dip-stick o-ring are the two weakest links in sealing it.

 

GD

Haha, I was looking at this just yesterday! I want a tighter seal on the oil dip-stick. Is there a standard o-ring you can get at a store or something you can order from Subaru?

 

And I got my oil cap to go on incredibly tight by adjusting the tabs, it still loosens up at the very last point of turning... So I back it off a little bit still.

The oil caps can be purchased brand new. Any auto parts store should be able to at least special order you one. I got one for Dorothy for about $6 at Checker. They special ordered one from Stant.

Brand new.

http://cgi.ebay.com/ebaymotors/Subaru-1600-1800-BRAT-XT-XT6-LOYALE-OIL-FILLER-CAP-NEW_W0QQitemZ320051968321QQihZ011QQcategoryZ33622QQrdZ1QQcmdZViewItem

cap must be tight, especially if the frantz dumps into the filler tube

 

if it ain't leakin, it's out

My 92 Loyale had same problem, so I backed it off and one day, it DISAPPEARED! Didn't hear it fall or any strange noise under hood, just went to check the oil and it was gone. Went to Autozone and for about 4 bucks got a new one that is tight right at the stops. Aparently there is a rubber gasket in the cap that gets hard and crushed by age and that is why caps get loose.