curious about valve lash setting/check

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pishta said:
Get the cam to its base circle using whatever method you want, MP decal, degrees or logical crank rotation looking at the opposite rocker. Spin the pushrod, and start cranking down the adjuster-you'll feel it drag when it touches the pushrod. From there, add your preload, or subtract lash on a mechanical. The TPI on an adjuster is 20 so 1 turn more is about .050 and fractions there of. Thats about in the middle of the preload range.
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thank you pishta, that's what I was trying to ask, where to start the load. when I did it a second time, I cranked until they stopped spinning and noticed it was a big difference. I'll set them with the 'drag' as you say. thank you, and all that have helped, much appreciated.
 
RustyRatRod said:
We're all good now. Shut up fool.
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Screenshot_20190603-104915.png

Lol...
 
Spinning the pushrod is the Chevy way to adjust rockers. U have to lift the push rod up and down to know when the play is taken up. If u do it by spinning the p/r lifters that are weak will collapse and u will have way too much preload. A quarter turn us lots. Preload is for hydraulic lifters. Lash is for solid lifters Kim
 
How about some photos of your valve Trane.

I thought 340s had hydrolic lifters, stamped (non adjustable) rockers. And non adjustable pushrods.

If you are using early adjustible rockers with hydrolic lifters I would do as someone else mentioned and adjust till the lifter is about mid travel.
 
oldkimmer said:
Spinning the pushrod is the Chevy way to adjust rockers. U have to lift the push rod up and down to know when the play is taken up. If u do it by spinning the p/r lifters that are weak will collapse and u will have way too much preload. A quarter turn us lots. Preload is for hydraulic lifters. Lash is for solid lifters Kim
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thanks Kim, I believe that is what was happening. thanks for your input.
 
oldkimmer said:
Spinning the pushrod is the Chevy way to adjust rockers. U have to lift the push rod up and down to know when the play is taken up. If u do it by spinning the p/r lifters that are weak will collapse and u will have way too much preload. A quarter turn us lots. Preload is for hydraulic lifters. Lash is for solid lifters Kim
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That's what I do. Pull the pushrod up and push it back down gently until all the slack is out.
 
Dana67Dart said:
How about some photos of your valve Trane.

I thought 340s had hydrolic lifters, stamped (non adjustable) rockers. And non adjustable pushrods.

If you are using early adjustible rockers with hydrolic lifters I would do as someone else mentioned and adjust till the lifter is about mid travel.
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rockers.jpg
 
By adjustment description and the picture, I do believe some of those are adjusted so tight that some of the valves are probably hanging open.
 
IQ52 said:
By adjustment description and the picture, I do believe some of those are adjusted so tight that some of the valves are probably hanging open.
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I wonder which pushrods he has?
 
IQ52 said:
By adjustment description and the picture, I do believe some of those are adjusted so tight that some of the valves are probably hanging open.
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I believe you are right sir, that's why I asked, and am so glad to have the help you all have offered.
 
oldmusclelover said:
I believe you are right sir, that's why I asked, and am so glad to have the help you all have offered.
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I think he's right, too. However, if you have the incorrect pushrods, for instance, if you have pushrods for solid lifters, they are shorter than those needed for hydraulic lifters with adjustable rockers, so that could explain the adjusters running out of room as well. Generally when they are adjusted right, with the correct length pushrods, you won't have any more than about 3 threads showing on the bottom side of the rocker at the pushrod.
 
Yes you don't want your adjusters way out.. my pushrods are almost but not touching the rocker. They're adjusted in just about as close as you can without needing a shorter pushrod.. the further out they are the more subject they are to breaking and that's definitely all bad instantly..
 
oldmusclelover said:
don't know Rusty, bought the car with engine in it.
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Well, if you follow our instructions on how to adjust the valves, you will know quickly which pushrods are in it. If the adjusters end up much like they are now with the rockers properly adjusted, I would not run it, because that means the pushrods are likely the wrong ones. However, if there's a good bit of adjuster sticking through the top when done, you may have the right ones. You'll just have to adjust a cylinder correctly to see. @krazykuda can help with the correct length pushrods if they are the solid lifter ones. He helped Eddie with his engine and they figured it out.
 
If those are in fact pushrods for solid lifters you're only 12 bolts away from replacing them with solids and a bump in performance... but then again you may need the correct cam for that as well LOL another rabbit hole and more bolts...
 
RustyRatRod said:
I think he's right, too. However, if you have the incorrect pushrods, for instance, if you have pushrods for solid lifters, they are shorter than those needed for hydraulic lifters with adjustable rockers, so that could explain the adjusters running out of room as well. Generally when they are adjusted right, with the correct length pushrods, you won't have any more than about 3 threads showing on the bottom side of the rocker at the pushrod.
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RustyRatRod said:
I think he's right, too. However, if you have the incorrect pushrods, for instance, if you have pushrods for solid lifters, they are shorter than those needed for hydraulic lifters with adjustable rockers, so that could explain the adjusters running out of room as well. Generally when they are adjusted right, with the correct length pushrods, you won't have any more than about 3 threads showing on the bottom side of the rocker at the pushrod.
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that was the second time through Rusty (cranking down to stop the push rod from spinning), and I believe Kim was right by saying I bled them out because they are weak. it was much better the first time when I just felt tension (or 'drag' as Pishta corrected me, thanks) and went a half turn after.
 
oldmusclelover said:
that was the second time through Rusty (cranking down to stop the push rod from spinning), and I believe Kim was right by saying I bled them out because they are weak. it was much better the first time when I just felt tension (or 'drag' as Pishta corrected me, thanks) and went a half turn after.
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That may be so. Just know you need to be careful with this and double check everything. You can do some catastrophic damage here if you're not really careful.
 
RustyRatRod said:
That may be so. Just know you need to be careful with this and double check everything. You can do some catastrophic damage here if you're not really careful.
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and that's why I'm here with you good folks. I'd rather ask than spend money I don't have. really do appreciate all of you and your help.
 
oldmusclelover said:
and that's why I'm here with you good folks. I'd rather ask than spend money I don't have. really do appreciate all of you and your help.
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You're most welcome. Let us know how it turns out.
 
Why did u want to adjust them? We’re they noisy? Solid lifter pushrods are longer than hydraulic p/r. U have to have the can on the base circle to adjust each cylinder. If u don’t understand how that is done, just ask. Kim
 
IQ52 said:
By adjustment description and the picture, I do believe some of those are adjusted so tight that some of the valves are probably hanging open.
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I agree. All the adjusters should be damn close to the same adjustment. You've got some that have the adjuster buried in the lock nut.

Do it again. Use a soft finger and as soon as the lash is gone, just not even enough to spin the pushrod...when the lash is gone...screw that adjuster down 3/4 of a turn and tighten the lock nut.

Done. But all the adjusters should be visually very close unless the base circle of the cam is off from lobe to lobe. But I haven't seen that since 1982.
 
oldkimmer said:
Why did u want to adjust them? We’re they noisy? Solid lifter pushrods are longer than hydraulic p/r. U have to have the can on the base circle to adjust each cylinder. If u don’t understand how that is done, just ask. Kim
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I thought they were shorter. My apologies. I caint remember every darn thing. lol
 
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