Bad News - Burning Blue!!

[GEARS]

So I decided to install the Comp 1.6:1 Roller Rockers last week along with the Mallory 6AL and mechanical steering box that I recently obtained for my highly modded 3.4L TBI S10 with a whopping 13,000 miles on it. Installing the ignition and steering box was a breeze, and installing the rockers was an even easier task!! I set the rockers to 5/8 of a turn past 0 lash. I also ground the pushrod guides to provide more pushrod clearance with the larger ratio rockers.

I fired it up outside the shop and there she sits idleing beautifully... not a tick, not a tack, not a click, not a clack.... I let it warm up to operating temperature, then I give it a few little revs.......... AND WTF BLUE SMOKE!!!!!!!!!!!!!!!

I run it some more... and find if I hold a high idle (2000 rpm), the smoke goes away. But if it sits and idles for a while and then I rev it, it puffs blue... but if I rev it like 5 times, by the 3rd time the blue dissapears.

Get it???

I shut it down, let it cool off, then pull the plugs..... nope no signs of oil!! Then I run a compression test.... yup still pulls about 200 psi per cylinder!!

At this point I blame valve seals ...

What do you guys think??

[GEARS]

I CAN'T see it being the rings as the spark plugs look perfectly clean, and the compression is exactly where its always been. There is also absolutely no change in oil pressure and the dipstick hasnt moved down.

I CAN see it being the valve seals. I have seen a few cases now of the crate motor coming with shitty valve seals and burning blue the way mine does. One forum had a member go through 3 crate motors, and finally on the third one he had GM replace the seals and all was good after that.

[1988GTU]

Maybe your lower intake gasket is torn and is leaking oil into the intake port now. How old is the PCV?

[GEARS]

The pcv is new, and I also tested it by leaving it out of the motor and it is not the problem.

So I learned that a bad oil ring will not cause low compression, so what I did is got my dad to drive behind me on the highway and watch when I floor it if anything comes out... Nope, not a hint of smoke of any kind! Its obviously not a ring.

I do see it being a possibility of being the intake manifold gasket... but we had the manifold trued when the motor was built and I have re-torqued the manifold bolts once every few months??

I still think its a valve seal or two or twelve, as it only smokes after idling for a while when there is high manifold vaccum.

[CNCguy]

The bright side is, if it's the seals, they can easily be changed without pulling the engine or the heads. Much easier and cheaper than a ring job.

[geoffinbc]

My money is on the fact that you don't have any exhaust valve stem seals. You can run them by buying Viton Small Block Chevy seals. You can ignore the problem because it wont cause any damage or just go in and pull all the spring and replace all the intake seals and add in the exhaust seals.

What spring and retainer combo are you using? Did you ditch the oil umbrella? Did you keep the O-ring under the valve locks installed?

[GEARS]

Whatever came in the crate motor, is what is in there. I will look into the viton stuff. I do know viton anything rocks.

I really hope its just the seals... if its more I mind as well just park the damn thing and do the whole blower build... but we will see shortly I guess. Its certainly not down on power, infact with the power steering pump gone and the new roller rockers and the Mallory 6AL, the truck has the most balls to date lol.

[geoffinbc]

Yea I don't think the exhaust got any seals. My S-10 does not have any exhaust seals and it burns oil on startup. My Trooper does have them and it never burns a drop.