i just picked up a used csb 350, i was told it is a 70's block with newer heads and a new edlebrock 1403 carb, and ran strong. the owner of the motor backed the valves off to keep the springs fresh. so after droppping the motor in i adjusted the valves according to the chiltons. get the motor to TDC and hit one set, rotate motor 360 and do the other set. when finished the motor had zero copression, so i thought i might have gotten it at BDC so i adjusted them again and the same thing??? so i called a freind over, who said the valves were to tight, so i cranked the motor over a few times while he backed off a few valves until it started. he said its better to adjust them with the motor running anyways, so while it was running he adjust them the best he could ( though he said hes never adjusted them fully cause he had some things to do) . it idles well now but during a constant speed it laods up and runs rich, and during acceleration it misses time to time.

i was wondering if anyone knows the correct way to adjust the valves while running? i have read to back off each valve until it chatters, then close it until it stops, then giving it 1/4 to 1/2 turn??? i hope i didnt bore you with this thread, but any help would be nice!

You got it right for adjusting it when running. Hopefully you didnt accidentally round the cam lobes when it was too tight. Make sure the lock nuts are still lock nuts, they are only supposed to be adjusted once because the lock wears off.

^Like he said and your last sentence. See if you can get the engine warm first, then adjust the valves 1/4 to 1/2 after the clatter stops. The engine should slow just slightly as you turn down the adjustment nut. This is the lifter pumping up. Don't sweat it just turn it down slowly till it stops clattering and do the last quarter or half in a smooth easy motion. If the cam is big go 1/4, close to stock 1/2. I personally do all mine at 1/4 turn. Hope you get it running right.

well there was so much noise going on i couldnt tell what was clattering, i tryed my damndest to get it right i felt lost though!!! but the funny thing is after i messed around with the valves its runing like a champ? but i want to make sure i have it exactally right! pretty much dont want anything to break? but i was told nothing should go wrong, aslong as i dont over tighten them! i was told if its running and i over tighten the engin will bog down.

I have never had any luck adjusting valves using the 360 method. What has worked best for me is to either do it running or do each cylinder individually.

easy way to adjust the valves...

watch the rocker arms. when one rocker arm for a cylinder is compressing a spring, the other should be on the base circle or close enough to adjust without starting the engine. spin the pushrod by hand as you tighten until you can feel tension on it, and there is no more slack. watch closely to make sure you dont overtighten it.

move to the next valve.

then, on startup, for a new engine, break the cam in by running the engine for 25-30 minutes varying the engine rpm from 2000-3000 rpm. Change the oil, set the timing, check for leaks, and THEN adjust the valves. then adjust the carb and reset the timing.

Grumpy is describing setting the valves with the engine off. You should be able to twist the pushrod between your fingers as you are tightening and feel a little drag. You adjust it when the valve spring is not compressed at all, that is the base circle. You can do a few cylinders at a time once you get used to recognizing which ones to adjust. You can also do it following the firing order, because both valves are closed at Top Dead Center on the power stroke. Not to be too elementary but the cam is like an egg, the pointed part at the top is when the valve opens, the round part at the bottom is when the valve is closed. (base circle or heel of the cam). If the engine slows down and recovers it is the lifter pumping up, If it slows down and runs crappy the valve is too tight. It is normal for a momentary slowing of the engine (a few seconds) then it will return to normal smooth running. I hope this helps and is not too long winded but the more you know, the easier it is to recognize when you are doing it right.

Grumpy is describing setting the valves with the engine off. You should be able to twist the pushrod between your fingers as you are tightening and feel a little drag. You adjust it when the valve spring is not compressed at all, that is the base circle. You can do a few cylinders at a time once you get used to recognizing which ones to adjust. You can also do it following the firing order, because both valves are closed at Top Dead Center on the power stroke. Not to be too elementary but the cam is like an egg, the pointed part at the top is when the valve opens, the round part at the bottom is when the valve is closed. (base circle or heel of the cam). If the engine slows down and recovers it is the lifter pumping up, If it slows down and runs crappy the valve is too tight. It is normal for a momentary slowing of the engine (a few seconds) then it will return to normal smooth running. I hope this helps and is not too long winded but the more you know, the easier it is to recognize when you are doing it right.

well worded.

sorry, wasnt trying to write for the completely ignorant... this isnt newbie, but i guess for most of these guys, it is newbie, eh?

jesus.... theyre supposed to know this before they get here.... .AREN'T THEY?

Yea I suppose so. But I remember the first time I tackled the valve adjustment thing myself and his comment about makin so much noise because they were all clattering touched a nerve...and I just had to try to help.

yes, i was just told fail safe way while running was to tighten the valve until the engine bogs down then back it off 1/2 turn and engine runns better??? kinda back aswards from the chattering method, but i found a so called professional to hopfully come over and show me the ropes! but i do understand when the motor bogs, the valve is to tight, im new to valve adjusment but understand the consept of the cam and timing! it was just hard to comprehend why the by book method didnt work?

yes, i was just told fail safe way while running was to tighten the valve until the engine bogs down then back it off 1/2 turn and engine runns better??? kinda back aswards from the chattering method, but i found a so called professional to hopfully come over and show me the ropes! but i do understand when the motor bogs, the valve is to tight, im new to valve adjusment but understand the consept of the cam and timing! it was just hard to comprehend why the by book method didnt work?

the book method does work.

some people used to use the book method to do solid lifters. it evolved into hydraulic lifters, where it is not quite as perfect. I dont use it with either solid or hydraulic lifters. im pretty picky, but my engines generally run pretty well.

the book method does work.

some people used to use the book method to do solid lifters. it evolved into hydraulic lifters, where it is not quite as perfect. I dont use it with either solid or hydraulic lifters. im pretty picky, but my engines generally run pretty well.

Judging from the videos of the mud truck, I'd concur and say its an understatement. The truck runs and sounds good.
Lumberjack, I am glad you have a grasp on valve operation I was not sure of your knowlege base and wanted you to understand. IMO tightening down till it bogs and runs rough, then backing off, is too tight.
I like to dead time (cold adjustment) the engine with both valves at TDC. Start at number 1, adjust both valves with the finger method, add 1/4 turn. Rotate the engine till number 8 is at TDC adjust both valves, next number 4...all the way through the firing order. Then when you start it nothing should be loose enough to clatter or click so loud you can't adjust it easily. The cold adjustment takes more time than other ways, but it is simple and works.

With regard to using the "finger method",IE: with lifter on the base circle, loosen the adjuster until definite slop is felt when turning push rod with your fingers, then tightening until all slick is gone. That last part separates a good job from a bad one. It takes a delicate touch to "feel" that point where all slack has been removed. I've found that at the very first sign of resistance when tightening the adjuster, is the right spot. Don't expect the push-rod to be dificult to turn. If it becomes difficult to turn, you've probably gone too far.

well i respect your opinions, cause theres only so much bullshit out there until you start to hear ideas from people that argue there point leading you in the drection of there ideas though the pride in there responce! the individual cylinder at TDC deff sounds the way to go, if you are as green as I in the valve world, but deff need to get the hange of it for my own experience(that is the proper point to call 0 lash, maybe thats were i messed up in the first place???) well ill be back hopefully soon to let you know the final verdict!

Lumberjack, the first part of your post sounds kinda funny. You said that the previous owner "backed the valves off to keep the springs fresh".....sounds like an excuse to cover himself for something that might have happened to the motor.
In light of that, if you can't get this motor to run right, don't rule out that he might have had flat cam lobe or two cause he didn't break it in right, or had the valves adjusted to tight.
Some people are momos, and will try to sell a heap of doo-doo for big dollars.

ya im picking up what ur laying down. but he did say he would give me my money back if there were any problems! so i guess we will see!, but all in all after my attempt it ran pretty strong, final attempt will happen tonight, i have a proffessional mechanic in the hot rod indusstry comming over to help out!!!

With regard to using the "finger method",IE: with lifter on the base circle, loosen the adjuster until definite slop is felt when turning push rod with your fingers, then tightening until all slick is gone. That last part separates a good job from a bad one. It takes a delicate touch to "feel" that point where all slack has been removed. I've found that at the very first sign of resistance when tightening the adjuster, is the right spot. Don't expect the push-rod to be dificult to turn. If it becomes difficult to turn, you've probably gone too far.

Very good description! Thanks for the clarification. With all this information and his help tonight, I think he should get there. You should have a nice running engine tomorrow. Let us know how it goes OK.

If it becomes difficult to turn, you've probably gone too far.

If it becomes difficult to turn you have DEFINITELY gone WAY too far. This is the mistake the rookies make all the time when adjusting hydraulic lifters.

Just finished a leak down test on the sons truck, with the valves at TDC the rockers will wiggle side to side. The pushrod will not move up and down though. Like was said earlier as you snug down the nut the slightest drag is the point that you stop and physically the pushrod should not move up and down.
I did the sons truck in Seattle when he was stationed up there and it was so damn cold and rainy (I was working in a carport with sheets of plastic to keep the water out) that I just dead timed it plus a quarter turn and ran it.
It was cold and miserable and my back was killing me. It run fine with no clatter, warmed it up, timed it and shipped it.
That was the first time I ever dead timed an engine and not readjusted the valves running. It lived, ran fine and serves him well for an old truck.
Started using a little oil so we tested the compression and ran a leak down.
Got a little oil buildup on a couple of plugs and some leaking past a couple valves. Got some oil burnoff on startup too, so we will pull the heads and do it again. Thankfully he is stationed in San Diego now so we will do the job here in California in much more agreeable weather.

well, i was stood up yesterday! wich really sucks, so it looks like im on my own from here, i am going the route of each individual valve at a time a TDC, rotate motor 90* yadda yadda, my only question is how exact do i have to when both valves closed, its obvioslly easy for 1 and 8? i am just going to try and watch the valves while i rotatr the motor, but i was thinking a reasonable idea would be to mark the balancer threw the first set, so threw the second you would have a closer idea, any ways just thought i would throw that out there, for some pointers, oh and i did get some new rocker nuts! im sure someone will say something about it, my old ones were getting soft, ill be back at the end of the day with results this time!!!

You should be able to see with the valve covers off when the valves are both closed. I turned the engine with the alternator and the plugs out so I could turn it and watch the valves move.

well had a hell of an idea! measured the balencr, divvided by four, and marked the balancer, rotated the the motor 90* for every valve, now she purrrrrrrs like a kittin, and roars like a monster!!! yaaaaaaaaaa! i only tighten each nalve 1/4 of a turn, cause i am a rook in the valve derp. and didnt want to over tighten them again!!! i figured if they clicket while running, another1/4 turn and all would be well! so after the job, there was some clicking, (soft but some!) and with 1/8 of a turn on all valves, the noise was all to b gone! deff sounds like a healthy 350 even with new stock exhaust! thanks so much 4 the great help! i am now a confedent valve adjuster! also found a soft cold valve adjustment finishing with a running valve adjustment might b the way 4 a rook! cause its deff better to b soft then too hard! not to usual in other dpartments, i would say its deff a nak for a pro, to get it done right the first time, but it pays to try!
thanks for all the help!

well had a hell of an idea! measured the balencr, divvided by four, and marked the balancer, rotated the the motor 90* for every valve, now she purrrrrrrs like a kittin, and roars like a monster!!! yaaaaaaaaaa! i only tighten each nalve 1/4 of a turn, cause i am a rook in the valve derp. and didnt want to over tighten them again!!! i figured if they clicket while running, another1/4 turn and all would be well! so after the job, there was some clicking, (soft but some!) and with 1/8 of a turn on all valves, the noise was all to b gone! deff sounds like a healthy 350 even with new stock exhaust! thanks so much 4 the great help! i am now a confedent valve adjuster! also found a soft cold valve adjustment finishing with a running valve adjustment might b the way 4 a rook! cause its deff better to b soft then too hard! not to usual in other dpartments, i would say its deff a nak for a pro, to get it done right the first time, but it pays to try!
thanks for all the help!

glad it worked for you.

x2, doesn't feel good to hear that engine run nicely? I m having a cool one for you:beer:

ok so ive only drivin the jeep for a bit and can here a valve clattering! but the motor is still running smooth as butter? so i was wondering on the next steps from here, was just thinking of finding it and adjust it while its running, unless this is not a wise idea! i thought i would run it buy you guys since you guys have help out b4, and were right on the money!

take a piece of hose, and put one end to the valve cover and the other to your ear.... or a broom handle, or something...., find where the rattle is....

remove the valve cover.

watch the rocker arms as it runs, and compare them to their neighbors.

you may find that you have a couple that are barely moving.


lets hope its not so... but be prepared.

not moving like, a worn cam i would imagin? from over tightening of the valves! lets hope not! we'll see! thanks!

What did you find out? Sometimes the nuts lose tension and you can replace them. Try adjusting it again and if it loosens up replace the nut. If the nut is snug and the lifter is barely moving then...you might have a toasted lobe on the cam. Usually when one nut is bad, they are all ready to be replaced.

generally, the nuts dont loosen. the end result is a bad cam, due to a lack of the right oil components. The amount of zinc and phosphorous have been cut back so drastically as to destroy the ability of our older cars to operate with flat tappet camshafts. these changes are done for emissions purposes, just as leaded gas was killed for emissions purposes.

I've had a couple back off, but generally your right it is not common. But if he was lucky enough to get by... On the oil, the Shell Rotella for diesels is supposed to be good break in oil. Would you run that all the time on a flat tappet engine now that the additives are being depleted on gasoline engine oil?

I've had a couple back off, but generally your right it is not common. But if he was lucky enough to get by... On the oil, the Shell Rotella for diesels is supposed to be good break in oil. Would you run that all the time on a flat tappet engine now that the additives are being depleted on gasoline engine oil?

yes, I would.

either that, or run synthetic oil with the same values.

break any engine in with a good oil, and then change to a synthetic oil

contrary to popular belief, you dont have to drive it 40k miles to seat the rings, either.

yes, I would.

either that, or run synthetic oil with the same values.

break any engine in with a good oil, and then change to a synthetic oil

contrary to popular belief, you dont have to drive it 40k miles to seat the rings, either.

40k miles? Wow thats crazy. When i finish an inframe I take it out for about an hour to seat the rings.

the motor is deff used, but i dunno how many miles are on it? ive already replaced the lifter nuts when i adjusted the last time! but ive been so busy with work i havent had time to check oout the problem! but hopefully today i can take a look! thank all for the input