Atomic1

Just trying to learn a bit about head internals as I investigate oil burning on a B16. I understand what a valve stem seal is, but what is a valve guide seal? Seems like the terminology is loosely used and I haven't had the opportunity to tear into a head to see for myself.

I'm thinking that the valve guides can be worn and cause the stem seals to leak, but not that they have seals themselves.

PyroProblem

Valve guide seal is the incorrect term for a valve STEM seal. I think some people just confuse the words.
heres a pic..
http://www.team-integra.net/images/B...gs/1010282.jpg

Atomic1

That's what I thought.

This thread on valve stem seals has been helpful https://honda-tech.com/forums/acura-integra-6/%2A%2A%2Ahow-%2A%2A%2A-install-valve-springs-valve-stem-seals-1604753/


So how common is it to wear valve guides out of spec? and how would they cause oil consumption?

Scott_Tucker

If your valve guides or valves stems wear you will have excessive valve guide to stem clearance. A new seal will not help an engine that has excessive guide to stem clearance for very long because the seal will get prematurely worn out as the valve rocks back and forth in the guide.

Both those terms mean the same thing. Although as someone else said, the correct term is valve stem seal.

Bad valve stem seals or worn out guides will cause the engine to burn oil when the engine is decelerating in gear. With the throttle closed, and the engine rpm high while decelerating (like when downshifting), vacuum in the intake port is high. Pressure in the crankcase will force oil past the guide and into the intake port.

Bad oil control rings will show up on hard acceleration (blue-ish smoke out the exhaust). A compression or leak-down test will tell you nothing about your oil control rings.

Atomic1

I thought a leakdown test WOULD tell me the condition of the oil control rings but NOT the valve stem seals.


So is there any way to determine if the guides are worn without pulling the head and having a machine shop look at it? It would be a waste to throw new stem seals on and not fix the problem. The engine has been well taken care of.... would it be surprising to have worn guides at 130,000 mi?

PyroProblem

Leakdown test mainly shows you the compression rings condition. (Think about how much tension the top rings have against the bore compared to the oil rings)

I dont think theres a standard way in testing valvestem seals, but at 130K miles and 10 years old + in a high revving b16, it might be time for a re-fresh...

If it comes down to it, rebuild the head first. Its cheaper,easier, and you should do it anyways if it ends up being the bottom end, so its not really a waste, even if you decide to go to a bigger block (hint hint)

but yeah, you gotta pull the head to accurately measure valvestem to guide wear.

Scott_Tucker

No, it will not. If your oil control rings were stuck, or if you even took them off the piston completely, your compression readings would be better than before due to the oil on the cylinder walls helping to seal the compression rings. Compression rings seal compression (cylinder pressure) and oil control rings control oil.

Atomic1

Makes sense. Thanks for the guidance guys.

Looks like I'll do a little testing first and probably plan on headwork and go from there.