Nickyloves442s

I bought a 1971 442 convertible a while back (my dream car) and it had been sitting for about 10 years. I changed the oil, put gas with seafoam in the tank, and changed the fuel pump, wires, etc. I got it running in November, and ran it periodically, but never drove the car, because its not licensed and has no plates. It ran really well. Tried to star it a couple of weeks ago, and it was making a bad noise up top. Pulled off the valve covers and discovered a bent pushrod caused by what I believe is sticking valves. I bought 2 new pushrods, and replaced the bent one and its cylinder partner. Ran the car, and heard the same noise, only to discover another bent pushrod. I believe that some of the pushrods may have been clogged from the sludge in the motor, causing no oil to help the valve stick in the guides. I also notice wear of the rockers against the bridges, etc.

I've been spraying penetrating fluid on the top of the valve stem hoping to loosen the sticky valves, and also ran treatment and atf fluid in the motor oil and cycled it through a couple of oil changes, etc.

I plan on doing a rebuild, but would.like to get the car running to plate it and so on and so forth.

I noticed there was wear on the rockers and bridges, and would like to replace the rockers, bridges and pushrods. What are your recommendations as far as where to get them, and best prices. I went to an engine supply house here in town, and the guy tried to sell me on roller rockers, to replace the bridge set up.

What are your opinions, any help is appreciated.

oldcutlass

Was there also old fuel in the tank, as it turns to a varnish that tends to gum up and cause things to stick when the engine cools down. Is it possible that one of the valves contacted the piston and bent, where as no amount of new pushrods will correct this issue?

Oldsmaniac

X2! had a similar situation, only real fix for me was to pull the heads for a valve job. The black sticky glue like tar in the valve guides was terrible.

MDchanic

Did you bend the same pushrod, or a different pushrod?

Remove the associated rockers and, using the pry tool of your choice (there is an official GM valve spring compressor available that uses the rocker pivot as a fulcrum) or maybe just a plastic mallet, confirm smooth, complete movement of the valves in question - if they don't move, or don't quite close, no matter what you do, you've probably got a bent valve.

If this is a stock engine, then replacing the rockers and pivots with stock units is completely fine.
You can get them at any auto parts store.

Note that slight wear on the bearing surfaces of the rocker and pivot is completely normal, but the aluminum factory pivots can wear out, producing excess valve lash and ticking.

- Eric

Nickyloves442s

Thanks guys, for the info. I don't think the valves are bent. I think the old gas may be causing a lot of it.