What are the symptoms of valve blow-by

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Dct5289

GT5 FTW
I have a b18c1, and i need to do the valve seals. It burns oil, but it doesn't leak, and im pretty sure its burning the oil through the valve seals.

So here are the symptoms im experiencing. I was going down a long slightly steep hill the other day engine braking at about 3000 rpms and when i got to the bottom there was a stop sign. So as i pulled away from the stop sign i see a significant amount of smoke rising up in the exhaust. It stops smoking shortly thereafter. This also happens when i rev it to around 7.5k to 8k and then shift, as soon as i stomp it in the next gear, a huge cloud of smoke trails me, but only for a few seconds.

Im guessing that oil is getting sucked by the valve seals aided by the combination of oil pressure and intake vacuum. But i want to make sure before i go through the valve seal replacement.


If it does happen to sound like valve seals, what is the best/easiest tool on the market for replacing the seals. (but not super expensive)

The head gasket is new and my compression is up around 200 on all four cylinders.
 
Could be valve stem seals, but I have also had a problem both in the past with my GSR and recently with my friends GSR swapped CRX that had the same kind of symptoms that I pretty much have narrowed down to bad oil control rings. A compression test won't show anything being wrong with the oil rings as long as the compression rings are ok.. and his engine has basically perfect compression like yours, but the valve seals are not leaking. From what you are describing it sounds more like blow-by than bad valve stem seals.
You can check the exhaust side valves relatively easily by pulling off the exhaust manifold from the head and inspecting the valve stems through the ports for any visible oil leaks, since they are usually the ones that start leaking first. If they look okay chances are it's not a valve stem seal problem.

Do you have any idea how many miles might be on your engine? Although it is possible to change the valve seals with the head on the car (not the best way to do the job IMO), you might want to consider pulling the head and installing new rings & rod bearings while replacing the valve seals and possibly resurfacing the valves at the same time.

On the other hand, if you want to just replace the valve seals and see if it helps there are some methods to that as well while leaving the head in place. The first one, which I would recommend, is to find a threaded fitting to put in your spark plug hole (such as a compression tester hose), and connect that to an air compressor to supply a constant supply of high pressure air into the cylinder. That will hold the valves in place and will allow you to remove the springs/retainers and change the valve stem seals without removing the head. If you feel inclined you can also change the valve springs at the same time for some upgraded units such as the ITR or similar. Another method which I don't feel is as good but has worked for many people, is to insert some nylon type rope into the spark plug hole and turn the engine over until the piston compresses the rope against the valves at TDC. It will hold the valves in place and allow you to do the same procedure.
 
Well when I got the engine it had around 70k miles on it. I have already pulled the head once and replaced alot of the seals, but I didnt have the tools or the time to do the valve stem seals. I guess either way its going to be a pain, but i'd rather not pull my engine out again and do the rings.

I'm guessing that my engine has around 110 or so k miles on it which would probably move me away from the rings, hopefully. However, I don't know how the previous owner drove the car so theres no way to tell.
 
You actually don't have to pull the engine to replace the rings. If you're going to pull the head eventually and replace the valve seals all you need to do to change the rings is pull the oil pan & crank girdle, and then you can unbolt the connecting rod caps and pull the pistons out and re-ring them.
 
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