The Stovebolt Site Forums The Shop Area Engine Shop noisy lifter

I have run my 58-62 235 many times for 30 minutes or so each time, and adjusted the valves. Hydraulic lifters. Upon closer inspection, I noticed a bent pushrod and that is where the noise was coming from. the push rod looked like it was rubbing against the hole and the rod was marked up on the side. I had a new one on hand and put it in, and now, I still get the noise and the new rod looks bent now. Rest of the valves sound real good. Now what? Bad hydraulic lifter? clean? What would cause that push rod to get bent?

Thanks all!

You've got a sticky valve guide, and the pushrod is getting bent by trying to force the valve open against some major resistance. It might be possible to work some carburetor cleaner down the valve guide from the top, but it's more likely you'll need to pull the head and clean up all the valve stems with a wire buffer, plus do a cleanup on the inside of the guides. If one is sticking, others are probably close to having the same problem. Bite the bullet and do a valve job.
Jerry

Purney,

Too bad. Before I went nuts on a valve job I would at the very least pull the sidecover and see what is going on, you might get lucky.

Stuart

I pulled the side cover and pulled the lifter out I think is causing the problem (or it could be the valve guide. What do I look for, little green men? or run it with the side cover off?

How do I clean the lifter?

Secondly, this valve with the bent pushrod was the one sticking early on before i got this beast running, so it could be the valve guide as mentioned. The valve is working but could the rapping be the valve not returning cleanly and the rocker arm slapping against it? Interesting thing. when I pulled the pushrod up the lifter came with it. Is that what it supposed to do?

Thanks!

If its just sticking dont waste time and money on a valve job unless you need one to begin with. This is fairly normal if there old gas in the lines or tank. I broke 4 rocker arms and bent a few pushrods on my 248 after everything was warmed up when I first got her running.

Spray a bunch of wd40 down onto the valve guides and use a sledge to tap the valves. Eventually this will dissolve whatever varnish is left on the guides.

You need to investigate a little more to. If you do a complete valve job and still have old gas in the lines, theyll just stick again and really tick you off.

Jeff

How about applying a little common sense here? How can a lifter, which is BELOW the pushrod, cause it to bend? The only parts above the pushrod are the rocker arm, and the valve stem. It's easy to check the rocker, especially with the pushrod removed- - - - -just grab it and see if it moves easily. It does? OK, the only other thing it can be is the valve sticking in the guide, which it's already done. Either do it right by cleaning up the valve stem and the guide, or buy a bunch of pushrods. Straightening a bent one is simply not an option.
Jerry

Push rod was bent exactly in the middle. Rocker moves fine. clacking sound must have been the pushrod slapping against engine as it was bending while running. I'll work the valve a bit more with cleaner. when I tighten down the screw in the rocker to take up lash, I can see the valve spring start to collapse so the valve does move.... I have clean gas running so I know that is not the problem.

Would it help to run that motor wash through again? I did that once last year when I got it runningk then put in clean oil.

How do you clean the lifter when you get it out?


Lots of great info. thanks guys.

I disagree. Ive bent several and straightened them just fine. Unless your building a high horsepower engine, even a little quirk in a pushrod shouldnt drastically effect these engines. I imagine Im not the only one in history to do this either. Lay them on an extremely flat surface and give them a roll. Watch where the wobble is and correct it, these engines arent rocket science.

1951purney, the pushrod will stick in the lifter just because of the viscosity of the oil. Give it a little shake and the lifter will drop right off.

Another thing, when I went through the gas lines in my COE I was amazed as the lines were about 95% plugged with the black tarry goo that gas turns into after years. I replaced the lines, there was no way I could have cleaned that gunk out, and it will dissolve with the new gas running through the lines and stick your valves. This happened repeatedly the first time I ran the 248, and like I said, I broke 4 rocker arms and bent several pushrods (all of which were straightened and reused).

Good luck! Jeff

I have to go with Jerry on this. While one can strighten out a pushrod, why bother when their not realy that expesnive to begin with? I had one that the top brke off of (still not sure why), went to th flaps, got a new one for about $8. They even had one in stock.

If it aint broke dont fix it.

I say straighten because my 248 has the really early style which are roughly 16" long and are scarce. They also used 2 other sizes more commonly found which were around 12-14" long. This is all by memory so my sizing may be off.

Push rods are about 4 bucks, Ill buy a few and just keep messing with it till it quits bending them. I have all new lines and using a clean gas can for a gas tank so I am not create more gunk.

I think the issue is the valve, but while I have the side cover off, should I clean the lifters? If so how?

Purney,

It sounds like your previous engine flush procedure got things pretty clean inside. I wouldn't mess with the lifters...they usually either work or don't. If you feel a burning need to take one apart, I have enclosed a exploded view of the lifter. Have fun!
http://chevy.tocmp.com/shop/1955/55csm0611.html

Stuart

Thanks stuart, next question, Can I just buy one or do I have to replace as a set?