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Valve Adjustment on a 305 Chevy? easy way of doing

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hey guys. I just got my IROC camaro back from the shop after a ton of rewiring. It runs 1,000,000 times better now that everything is the way its supposed to be. The question i have is what they told me i should do. They said they heard a bit of lifter noise and suggested that when someone replaced the cam and lifters they didnt go back in and readjust them when the engine was hot. They told me i should do it with the engine running and warmed up. Is there an easier way to do this that will work just as well? they were suggesting cutting an old valvecover to get at the rockers and not get hot oil all over my headers.

 

Just so everyone knows, this is not a dealership. I am not taking it back to the chevy dealer. They did not know what they were doing. This is a small repair and restoration shop that specializes in Corvettes. Since a camaro and a corvette are very similar under the hood they had no problems redoing the wiring for me.

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Assuming "regular hydraulic lifter" Chev V-8)

 

1) I am not going to tell you that there is a clean way to do this, because there isn't one, no matter what you do there will be oil.

2) cut the center out of an old tin valve cover (a slot wide enough to get a socket in, front to back)

3) Or buy a box of these:

http://www.lislecorp.com/tool_detail.cfm?detail=570

(this is what I use)

 

Hydraulic lifter only:

With the engine warmed up (turned off) whip the valve cover off, and install oil stoppers, or cut valve cover.

Start up, back off rocker arm till it "clicks", then tighten until it stops, then slowly add 1 full turn (by "the book"). I myself only add 1/4 turn, but whatever works for you, and the state of your lifters.

Carry on doing the same for each rocker arm.

 

NOTE: solid lifters are a different story!

 

Now, the 305 Chev engine is KNOWN to wear out valve guides. The noise of a sloppy guide in these engines is like the noise you describe. If AFTER adjusting the valves the noise persists, you isolate the noise maker with a stethoscope

http://www.lislecorp.com/tool_detail.cfm?detail=1062

then using the wooden handle on your favorite hammer, you insert the wood between the valve springs, prying carefully/gently one to the next, if the noise goes, you have a bad valve guide.

Pull both heads and send to a machine shop for guide replacement, no knurling, unless you decide to install proper umbrella valve seals.

When you get your heads back throw the 205 thermostat in the garbage and install a 195 MAX.

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You can roll the motor over manually, one cycle at a time, and adjust each valve with a feeler gauge. But that takes more time. It is technically the "correct" way to do it, but I've always found the way your shop described to work much much better.

 

It really isn't as big of a deal as it sounds. I've done it to alot of vehicles without even using the cut up valve cover trick. It really just depends on if your heads have much of a lip or not. If they have a 1/2 inch lip or better, i'd do it without a valve cover, just DO NOT REV THE MOTOR UP. That will make a little mess.

 

It seems a little hectic the first time you do it, and honestly, you may bend a pushrod your first time, but it's so hard to hurt a healthy v8 that there really isn't much to worry about. Just go real slow, there's no rush. Take your time, and loosen the nut a little first to get a sound reference point, then work your way in slowly until it quiets out. Then it's anywhere from 1/8 to 3/4 of a turn further (depending on who you ask). I like to go from 1/4 to 1/2 a turn further, especially on an older v8 where the cam may be getting tired.

 

Just whatever ammount you decide to go past the point of quiet, BE CONSISTENT. If you decide to go a 1/4 turn further, do the same exact ammount on all of the valves. Don't do 1/4 on this one, and 1/2 on the next.

 

There's alot of literature on this all over the place. Or better yet, find and old guy at the parts house that like small blocks. That'd be the best source of info.

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Ok thanks guys. I figured what these guys told me was the right way to do it but i wasnt sure. It is a hydro engine. As for the cam/lifters they are both within the last 10,000 miles but 4 years ago. This car did alot of sitting in a garage before i got my hands on it.

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Yeah, the way they told you to do it pretty much is the easy way to do it. The biggest thing about doing this job is taking your time. Don't get in a rush, because that's how pushrods get bent :grin: ! Also, you couldn't have a better, or more forgiving motor to learn how to do this kind of stuff on. The fact that there's a small block Chevy swap kit for pretty much every car that will hold one tells you that you are working from a very solid platform.

 

Good luck man!

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You get your best performance in a "zero lash" condition.

When you back off the adjuster until it clicks, you are forcing the hydraulic lifter into it's fully extended position (caused by the engine's oil pressure), turning it into, in effect, a solid lifter. When you tighten it back down, to quiet it, anything past the disappearance of noise, forces the lifter to operate within it's hydraulic cushion. You will see/hear the engine slow up a bit as you tighten into this zone before the lifter self adjusts and allows the engine to run normally/smoothly.

 

If you encounter one that won't go quiet, do the side loading test, as I described above, before you condemn the lifter.

 

Adjusting Chev valves in this way has been going on since 1955 consider the history while you are doing it.

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Reveeen is excatly right. I owned small blocks for decades. Learned about them from a friend that built GMs when they were built in Mass. The modified valve cover is the best way to go. I had a set that I cut, but long ago gave or threw it way when I found soobs. The only real issue these motors had were a cam lobe at the front and/or back of cam would wear down prematurely. You replaced the cam so you should be golden for a long time.

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hey guys. I just got my IROC camaro back from the shop after a ton of rewiring. It runs 1,000,000 times better now that everything is the way its supposed to be. The question i have is what they told me i should do. They said they heard a bit of lifter noise and suggested that when someone replaced the cam and lifters they didnt go back in and readjust them when the engine was hot. They told me i should do it with the engine running and warmed up. Is there an easier way to do this that will work just as well? they were suggesting cutting an old valvecover to get at the rockers and not get hot oil all over my headers.

 

Just so everyone knows, this is not a dealership. I am not taking it back to the chevy dealer. They did not know what they were doing. This is a small repair and restoration shop that specializes in Corvettes. Since a camaro and a corvette are very similar under the hood they had no problems redoing the wiring for me.

 

I have a set of Mister Gasket...clips that will stop all the spraying oil.

 

 

But you don't. One valve cover off, adjust all of them. Fire extinguisher handy. Repeat other side.

 

 

That isn't the whole story.

 

Doug

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I suscribe to the school of thought that believes that the lifter plunger should be set in the middle of it's stroke and then left alone. Hydraulic lifter engines, of course.

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The only real issue these motors had were a cam lobe at the front and/or back of cam would wear down prematurely. You replaced the cam so you should be golden for a long time.

 

And by prematurely, you mean after 150,000 or so miles. :) And all that while making an honest 250 hp.

 

Bless the small block Chevrolet.

 

Where would the world be without it?

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No actually they'd be worn @ around 60k but it didn't get bad enough to notice until around 150k. I've seen dozens of small block cams with less than 100k with worn cam lobe(s). It's just that it is such a good engine as a whole that it runs fine with that condition for a long time. God bless the small block 283 / 305 / 327 / 350 / 400. Now put any of those with a awd and you got yourself a machine. HUMMER

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