I was a bit worried yesterday when I went to do a spontanious compression test on my d16y8 in my 1999 honda civic si (USDM Ex model). I pulled the wires off the plugs for 1-3, but when I get to 4... The wire pulled a good amount of oil to the surface of the valve cover. Im not a car guru, but I know oil does NOT go in here lol. I took the initiative to buy a valve cover gasket, and spark plug tube seals... but obviously this is a common issue as Im seeing this more and more, so Im curious if there is a few possible causes of this? Im pretty sure my rings are fine, Despite the oil I still had 150-150-150-150 psi across the board for all cylinders. Im not blowing blue smoke (from what I can tell), its all internal leaking, MINIMUM drops on the ground from day to day. any opinions? appreciate it guys

 

p.s I have not installed either the NEW valve cover gasket or spark plug tube seals, I am awaiting more opinions before I start replacing things.. I'd rather do it all at once if there could be more. my buddys are all civic guys and got me into them, and they said its probably the tube seals.

 

Probably just tube seals. Might as well buy OEM plugs, wires, cap, rotor if have not done it in a while.

 

seal got old and started leaking oil it happens I wouldn't worry about it again unless you replace the seals and 2 days later it has a bunch of oil in it again

 

Its the valve cover plug hole gaskets.

They get old and start to leak oil into the plug area.
Just replace them with oem seals.

 

So unless leaking continues after this is all repaired, I shouldn't assume the Lower spark plug o-rings need changing as well?

 

yeah its the seals where the Valve cover meets the head, swap em out with some new ones, Id suggest a Valve cover gasket to if your spark plug tube seals are leaking.

common problem easy fix

 

there are no lower tube seals on a y8. just the ones on the vc.

 

yup what he said too,


I think you have your plan of attack now get it done lol

 

replaced the vc seals and no more oil, yay. however, I thought this was my major oil leak. im still leaking quite a bit of oil. any other common areas on a y8 i should consider checking out?

 

vtec solenoid gasket, inner and outer distributor o rings, oil pan gasket, front and rear main seals.

Just to name a few. Clean your engine and bay until it's spotless, and work from there.

 

From 1999 I would assume it has quite a few miles on it. The three enemies of seals are: time, heat, and seal/swell characteristics depending on the oil you use.

By 60,000 miles (or any multiple of it) certain seals are going to start to harden up. The Valve cover gasket, spark plug tube gaskets, and valve cover bolt gaskets are prime examples. They suffer the most because they don't really get cooled by oil and aren't in constant contact with it. For the top end, those seals, your distributor o-ring seal, and your camshaft seal(s), and the PCV system (if you have one) are going to be the major contributors up top. Below that you have your head gasket, which doesn't typically leak oil externally and if it is leaking oil INTERNALLY you've got a serious problem. An occasional cause (and where it is on the particular car determines obviously if it's a top or bottom leak) is the oil pressure sensor. Sometimes the thread sealant on it fails and and oil leak starts.

After that you have the oil pump seal, front & rear main seals (crankshaft), and your oil pan seal. The latter three are your best bet, but if you have everything apart to replace them you would replace the oil pump seal... and depending on your mileage a whole bunch of other stuff.

Take some pictures, be observant, jack up the car and place it on jack stands at the proper lift points and get underneath and take a look around and some pictures.

Get back to us.

 

FYI My most recent 'decent' size top end oil leak was the distributor's sealing o-ring.