Car Analogy

Thomas Guide, redo the smoke test with the intake blocked off where you removed the filter. You could use just Saran wrap or something like that.

Imagine trying to test your garden hose for leaks with no sprayer attached to the end, just letting the water spill out the end. With no pressure building up, water won't have much incentive to force its way out the leaks.

Thomas Guide

Should have added this detail as I didn't think it mattered, I actually got the Lisle Vacuum hose caps, and there was one size that fit the intake hose (note the little yellow hose cap in the other pictures, it's the same set). I blocked it off, and after about a minute a lot of pressure built up and it finally just popped off and all the smoke poured out of it. I did this a few times holding the yellow cap on, I also stuffed a rag in the hole and also used blue painters tape to hold the cap in place but the smoke had no where to go and it would pop that sucker right off.

Thomas Guide

It's called breather tube hose, and I have been writing about it here:

https://www.s2ki.com/forums/s2000-un...meter-1191700/

You probably don't need to replace it unless it's cracked, Honda sells this tube as a bulk hose, so you get 4 feet of it and just cut what you need. I would recommend replacing all the other little Orings and gaskets that Deckoz mentions instead.

N777CK T

Ok thanks Thomas, so updating this list again:

PCV Valve - Honda Part Number - 17130-PV3-013 - £49.27 - https://www.lingshondaparts.com/part...=17130-PV3-013
PCV Valve grommet - Honda Part Number - 17139-PK1-000 - £4.96 - https://www.lingshondaparts.com/part-search?partnumber=17139-PK1-000
New Dip Stick - Honda Part Number - 15650-PCX-006 - £41.69 - https://www.lingshondaparts.com/part...=15650-PCX-006
Oil cap gasket - Honda Part Number (please check this) - 15613-PC6-000 - £8.56 - https://www.lingshondaparts.com/part...ber=PFKL315510
Breather Tube Hose (you get 4ft worth) - Honda Part Number - 95005-12001-10m - £66.26 - https://www.lingshondaparts.com/part...5005-12001-10m

All gaskets on the valve cover and all gaskets on front timing cover:

TCT O Rings
VTEC Solenoid Gaskets
Valve cover Gasket
Spark Tube (x4?)
Valve Bolt Gaskets
VTEC Oil Pressure O-Ring
TDC O-Rings
TCT Peep Washer
Cam Idle Gear O-Ring
Valve Stem Seals !

Optional Extras?
(2004-2005) Cylinder Rocker Cover - Honda Part Number (please check this for model year - I have searched a 2005 here) 12310-PCX-010 - £628.25 - https://www.lingshondaparts.com/part...ber=PFKL273137
(TSX PCV to go with updated rocker?)...

So hang on a second, this isn't a "relatively cheap" fix for most people if you still need to have your valve stem seals done too, just a warning that there are some extra steps including having these replaced?

treimche

I'm still wondering if anyone has done compression and leak down tests before and after fixing their crank case leaks. According to the theory of this thread, compression and leak down should improve after sealing up the crank case, right? Or am I just crazy?

Here's my thought process. Car is burning oil, and has a leaky valve cover/oil cap/dip stick/etc. This means oil is getting past the piston rings and up into the combustion chambers. After fixing the air leaks related to crank case pressure/vacuum, car stops burning oil. So this means that the proper amount of crank case vacuum is needed to make the piston rings seal properly. With this being said, shouldn't compression numbers increase and leak down numbers decrease as well?

VashTheStampede

That is an INCREDIBLY expensive PCV valve. My goodness.

Deckoz

I can redo mine this weekend possibly if I have time... Compression shouldn't change much, and neither should the leakdleak. The theory is about moving pistons not stationary pistons. During the intakeintak stroke vacuum is on both the cylinder and crankcase, the pistons must be displaced. When the crank case has low vacuum or positive pressure, but the cylinder has vacuum, oil can get by the rings easier.

As well to your comment, burning oil doesn't always mean ring seating. Which is why I mentioned valve seals at one point to. Positive pressure in the crank case, with bad valve seals, is going to push oil past the seals down the guides and into the runners.

Its not as simple as static leak-down and compression tests. But if your test come out good, like mine(210psi across the board on an ap1 f20 - 5 crank compression test, and 6-8% leakdown). And you are burning oil, then the point of this thread should make some sense. Solve crank case pressure.

As I'm pretty sure I mentioned this earlier, it doesn't matter much on boosted cars, as they hardly ever have vacuum in the combustion chamber, and the pressure in the cylinder is higher than that of the crankcase, during the intake down stroke, keeping pressure on the rings.

treimche

Thanks for your explanation, this makes a lot more sense in my head now.

Filigranas

please help again here, my engine might be bad

https://www.s2ki.com/forums/s2000-un...1190696/page5/

N777CK T