B18c7 white smoke under full throttle

[Dyln.bxtr]

I've replaced the PCV valve and it seems to still be smoking, but again. Only during vtec.
I'll try doing a compression test across the cylinders and see what I come up with.

[Super-DA9]

I've replaced the PCV valve and it seems to still be smoking, but again. Only during vtec.
I'll try doing a compression test across the cylinders and see what I come up with.

If the compression test comes up good then your valve guides and seals are most likely worn out. Happens to all B series (and most engines in general) it's just a matter of when. Fixing involves removing the head and taking it to a machine shop/engine builder. Alternatively, use a thicker engine oil and it should reduce the smoke.

[cbauto]

If the compression test comes up good then your valve guides and seals are most likely worn out. Happens to all B series (and most engines in general) it's just a matter of when. Fixing involves removing the head and taking it to a machine shop/engine builder. Alternatively, use a thicker engine oil and it should reduce the smoke.

Use best in market

[Dyln.bxtr]

Yeah, I've increased the oil to 15w50 and not willing to go much higher.

[Super-DA9]

Yeah, I've increased the oil to 15w50 and not willing to go much higher.

Well then you know what the solution is.

[Dyln.bxtr]

I have no idea what the solution is.
The 10w40 was burning a shit ton, the 15w50 is burning oil still.
The PCV valve has been replaced.
Compression I still haven't done, but will find out whether it is a bad seal when done.

[curtis265]

sounds like you need a bit of work done..

[Super-DA9]

I have no idea what the solution is.
The 10w40 was burning a shit ton, the 15w50 is burning oil still.
The PCV valve has been replaced.
Compression I still haven't done, but will find out whether it is a bad seal when done.

Read this again..

If the compression test comes up good then your valve guides and seals are most likely worn out. Happens to all B series (and most engines in general) it's just a matter of when. Fixing involves removing the head and taking it to a machine shop/engine builder. Alternatively, use a thicker engine oil and it should reduce the smoke.

Dyln pls

[Dyln.bxtr]

Oh... I thought you were responding to the oil change... My bad.

[amant02]

Mate, I wouldn't even worry with a compression test. Do a leak down test if you want to know for sure.

If you really worried. Take the block out and send her to machine shop ~$500 (depending on how far you wanna go whats really broken) add ~1k if you cannot remove and disassemble yourself.

When you get the motor back your vtec will go BWAHHHHHHHHH!

Best time to add cams or b20 if you ask me. I'd spend that extra 2k on a better valve train and rev to 9k on sweet cams. Add that extra offt to your BWAHHHHHHH!

[Super-DA9]

Mate, I wouldn't even worry with a compression test. Do a leak down test if you want to know for sure.

If you really worried. Take the block out and send her to machine shop ~$500 (depending on how far you wanna go whats really broken) add ~1k if you cannot remove and disassemble yourself.

When you get the motor back your vtec will go BWAHHHHHHHHH!

Best time to add cams or b20 if you ask me. I'd spend that extra 2k on a better valve train and rev to 9k on sweet cams. Add that extra offt to your BWAHHHHHHH!

Fair call. But just FYI if he was to take this advice and just go straight to rebuilding the block, but it turns out to be seals in the head that was causing the oil burn then he is back to square one again. Burning loads of oil and smoking.

The information we've been given seems to point toward top end problems. He says the burning/smoke happens at high RPM (vtec) which is when the engine creates significant enough vacuum to pull oil through the valve guides/seals if they are worn enough. It's extremely common on old B series.

I've had piston rings that weren't sealing properly before, it smokes a LOT and not just under high vacuum.

A compression test or a leakdown test will both give you an idea of how well the piston rings are sealing. Only one of them is more available and does not require an air compressor to perform. If we were testing for bent valves, that would be a different story.

So in theory (and in my experience building one of these), if a compression test or leakdown test yields acceptable results/figures then it can really only be one thing considering the PCV valve has been removed from the equation.

[Dyln.bxtr]

The compression test is showing an even compression across each of the pistons. Due to the tester I was using (rubber wedge to seal) which is designed for old Holden v8's (old mans 308 and my 253) with far lower compression, I couldn't get a solid answer. But the tests were within 50kpa of each other.
Is there any definitive way of testing leaking seals and guides? Or would I be best to just replace them rather than go through the hassle of testing??

On a lighter note though, The nutter has been getting a few touches of cosmetics.