Junkyard Vortec

[pontiacgp]

Still wonder why it spit the pushrod out ? A goods clean and a "rattle can" rebuild and you should have a good little motor on your hands

my guess is the valve is seized and rocker arm won the fight

 

[Opie Knievel]

It looks like you saw the worst of it and it looks good. Looks like 062 heads and along with the block heater would say it from a truck. I would also guess that it has been apart - someone correct me if I'm wrong - it looks like a felpro oil pan gasket and the blue on the heads would indicate felpro gaskets there(plus brass plugs). The pistons don't indicate over bore(check it) and you have PM rods. Engine probably got shut when the push rod created the noise and the engine ran crappy. looks like the spider tray and the guide held the lifter in place. Your probably right about getting it running.

I was pretty happy with what I saw. Before I got it apart I was guessing that maybe the problem was a spun bearing or something along those lines. 2 damaged pushrods sounds a lot better to me.
You are right, they are 062 heads.

I do know that the engine came from a '99 Yukon 4x4. It definitely looks like someone had been inside this engine recently. New gaskets (all Fel-Pro), brass freeze plugs, way too clean inside. I scraped the carbon off the pistons, no overbore numbers on them.

 

[Opie Knievel]

my guess is the valve is seized and rocker arm won the fight

Sounds like a possibility. I haven't given the heads a thorough check yet. Other than that, what else could have caused the pushrod failure? Rocker arm nut too tight?

 

[pontiacgp]

I don't think they used the 062 on truck engines, the 906 vortec heads had harden valve seats and were used on the trucks

 

[pontiacgp]

Sounds like a possibility. I haven't given the heads a thorough check yet. Other than that, what else could have caused the pushrod failure? Rocker arm nut too tight?

rocker arm too tight would cause a rough idle and it could damage the lifter but the lifter you took out was in one piece

 

[Opie Knievel]

Still wonder why it spit the pushrod out ? A goods clean and a "rattle can" rebuild and you should have a good little motor on your hands

I'm hoping this is gonna be a cheap engine to get running again. My basic plan right now is to make sure the heads and all of the bearings are good. If they are, get a cam, valve springs, intake, and pushrods. I might have to do a little machining on the valve guides for better springs. I'm not sure yet.

I'm probably gonna go with a carburetor but if I could find an affordable EFI setup, I'd like to try it.

 

[Longroof79]

Still wonder why it spit the pushrod out ? A goods clean and a "rattle can" rebuild and you should have a good little motor on your hands

I agree. That is a bit of a conundrum. Also, why would only one pushrod be affected?
I guess it could be attributed to either a rocker arm locknut that prematurely loosened up, a rocker stud that pulled out, but you more than likely would've discovered that...a defective self aligning rocker arm..? I'm just running across the possibilities. I suppose even a defective pushrod could be a consideration.

 

[Opie Knievel]

my guess is the valve is seized and rocker arm won the fight

I agree. That is a bit of a conundrum. Also, why would only one pushrod be affected?
I guess it could be attributed to either a rocker arm locknut that prematurely loosened up, a rocker stud that pulled out, but you more than likely would've discovered that...a defective self aligning rocker arm..? I'm just running across the possibilities. I suppose even a defective pushrod could be a consideration.

I think PontiacGP is right. Seems like the intake valve on cylinder 7 is stuck. I installed a couple of pushrods and turned the engine over by hand. The exhaust valve opens and closes fine. When it's the intake valves turn, I get resistance. A lot of resistance. I'm pretty sure that's the reason for the destroyed pushrod. I can't find any other reason. Thanks PontiacGP.

Any recommendations on the best way to unstick this valve?

 

[Opie Knievel]

I got the valve unstuck. I just removed the rocker arm and gently tapped the tip of the valve stem with a small hammer.

Upon further inspection/experimentation I think that the rocker arm was too tight on that valve. Just to prove it to myself I adjusted it too tight and bent another pushrod. (I wasn't exactly planning on bending one, but now that I accidentally did, I can see how having the rockers too tight could have been the problem.) I think I had it too tight when I was turning the engine over by hand a few minutes ago too.

After I actually thought about how to adjust the rockers and tried it that way, the valves open and close smoothly now. It's been way too long since I've built an engine.

 

[64nailhead]

I don't think you're correct in that the valve being adjusted to tight is the cause of the bent/bending pushrods. Get the valve spring off and remove the valve. Something else is up there IMO. With no preload on the lifter there should be no way the pushrod should bend. If you adjusted the valve to tight, then the valve should open once the lifter bottoms out.

X2 with the valve is stuck, or possibly bent. I couldn't see in the pic, but is that valve tuliped?

Post some pics of the valve please