I'm having them too ... the SBC problems that is. I have so many SBC's apart and spread out all over my garage right now....blocks, cranks, heads, pans, intakes......trying to make one good one out of the lot. Sounds a lot easier than it is....for me anywho.
He's got a sbc vortec, w/ early heads and he has an iissue with bending pushrods. The first time, it bent 2 pushrods and the lifters came apart. Now he has bent pushrods and the lifters seem to be ok. He pulled the intake and a lifter was laying in the valley. I don't know maybe a bad cam?
I think he will be glad to get some answers anywhere he can. The valves were set at 3/4 turn after quiet. He has been on here about 2 years. I called him and he is retyping. Soon to come
We checked coil bind today and seems to be no issues. I don't think there are any issues w/ running the early heads but unsure.
at first i thought it was a funny thread...laughed my ass off at first...well...now that I know its serious, it could be the cylinder filling with unburnt fuel due to a bad coil or spark plug...maybe also preignition probs....I hope you solve your issues....but hey, welcome to the HAMB!
I called him and he will post under his name pontiac4903 His wifes isnt working!!! That is funny . He will try again
Sorry for all the problems. I logged in under the wife's user name and everything appears to be ok. I type and type and type, get ready to send and the damn thing says I need to sign in. Been there and done it. Then it erases the message. HAPPENED THREE TIMES, I'M TIRED AND CAN'T TYPE. SORRY AGAIN.
That happened to me a lot too......now when i finish typing I "copy" using the right click and then I can "paste" it back in if it goes missing..works great. There is obviously a mechanical problem here. Valves hitting pistons, valve guides hitting retainers, valve springs stacking up...that kinda thing. Are you running a massive cam? Do you have adequate valve to piston clearance? If the pushrod bends enough it will fall out of position, allowing the lifters to be thrown up out of their bores. When is he having these problems? As soon as it is started? During a 6500 rpm 3rd to 4th shift? I can't see it being a cam problem. I am assuming you are using the lifters that were made for that engine. They can't (?) get "caught" on anything. They simply push the pushrod. Now something is stopping the pushrod from being pushed up...mechanical interference of some sort. Are you using a large cam, but aren't using the "long slot" rockers maybe? You can run Vortec heads on the earlier engines so I assume you can run early heads on a Vortec engine.
We pulled the heads and valves today, all clerances are good. He was unaware of any issues. The first issue was found when he bought the engine from a buddy, ran a comp. test and found the issue. This time it was found when installing a new intake. He did not notice anything.
wonder what that was??? but hey my balls itch not unlike the crabs but more like lobsters!!! i wonder if any of my HAMB brothers can help me with that??
If the slot in the rocker is not long enough (not allowing enough movement) the pushrod will bend. Are you running a large cam or is it stock? With the heads back on (don't use new head gaskets, you aren't going to be firing the engine this way, just mocking it up so you can check stuff, you may need to pull the heads again) and the intake off and the valve covers off, turn it over SLOWLY by hand. There is something binding here and it should be fairly obvious. Just set the lifters, rockers and pushrods for one cylinder at a time and turn the engine over by hand. Did you use clay to check for valve to piston clearance? Did you remove the clay? Not making fun, anything is possible.
in the meantime try applying listerine....hey its an antiseptic....go get yourself diagnosed correctly though with your honkey ass doc! and wash your hands after scratching your balls!
Speaking of rockers, you do know that with early heads you can use late or early rockers but with late (86 & newer) heads you must use late rockers if the pushrod hole in the head is round & not slotted. Van
That is certainly possible...I just assumed the shortblock was Vortec and the heads (rockers included) were old style. That would be a nice easy fix, hope you're right. So hard to diagnose when it isn't right there in front of you. Sorry Vandy...I got this in before I saw your post. That is interesting, one of these possibilites has to solve their problems.
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