Setting valve lash

[Licensed to kill]

I've been researching the setting of the valve lash on my C59A but am still left will some things being unclear. First, what should the lash be set at?. there seems to be quite a few different numbers out there. I'm thinking .014EXH and .010INT but have seen other numbers given as high as .018 and some suggesting the same lash on INT and EXH. The next thing that is not clear is what prevents the adjustment screw from "self adjusting". There is no lock nut that I can see and I've read that some use, what I gather, is two sections of thread slightly out of phase from one another to create a friction grip to prevent the screws from moving easily (or something to that effect). This seems to me like it would work as long as you are only adjusting the screw in to increase lash. As soon as you have to back it out to reduce the lash, the tension would be lost to my way of thinking. Could use blue locktite??. I'm thinking of doing my lash adjustments out of the engine so using locktite should not be too difficult unless there is a reason not to use it or it's just not necessary. Just looking for some clarification and insight before I start.

[JSeery]

The setting depends on the cam, different cams will have different valve clearances. You need to use the setting for the cam you are using.

The adjustment screw is held by tension and if it the tension is not correct they will move! One thing that will loosen them up is moving the screw around, so it should only be moved as required to adjust the clearance. It should be fairly difficult to move. Moving the adjuster in or out is not an issue, excess adjusting is. There are ways to tighten up loose adjuster threads if required.

Not sure how you are going to set them outside of the engine. If you get the first set of lifters adjusted, then you set the other lifters to that height, but that is still just a starting point. The final adjustment will have to be in the block and will require a couple of rechecks.

[GB SISSON]

Search my thread from a year or two ago called 'Light in the Lifters'. There was a lot of good info added by experienced barners. I showed a quasi-scientific method to check if the lifter's thread was tight enough to hold in service, aided by guys way smarter than me. EDIT: 'Loose in the lifters'

[Licensed to kill]

Originally Posted by JSeery

The setting depends on the cam, different cams will have different valve clearances. You need to use the setting for the cam you are using.

I have no idea what can I have. It's just what was in the engine. All I can tell by looking at it is that it appears to have absolute minimal duration, sharp lobes and rather straight ramps.

The adjustment screw is held by tension and if it the tension is not correct they will move! One thing that will loosen them up is moving the screw around, so it should only be moved as required to adjust the clearance. It should be fairly difficult to move. Moving the adjuster in or out is not an issue, excess adjusting is. There are ways to tighten up loose adjuster threads if required.

Yes, my plan is to move them as little as possible, the reason I was planning to adjust out of the engine thinking it would be easier to adjust just once and get it precise (unless I'm overlooking something).

Not sure how you are going to set them outside of the engine.

The plan is to put the lifters in (one at a time) on the cams heal, put the valve/guide in (no spring) and, while firmly pressing on the valve to ensure that it is seated, take a measurement with feeler gauge, then remove the lifter and adjust using a micrometer. Example, if I want .014 and get a feeler gauge measurement of .018, I check the length of the lifter with the micrometer, then adjust it .004 longer (measured with the micrometer) and, theoretically, when put back in should be exactly .014 (double checked with feeler gauge of course). I'm thinking that I can set all of the lashes this way, one at a time with only the cam in the block, not have to rotate the cam with pressure on any lifters and have everything set before final assembly. Seems like the logical way to do it to me but I'm sure I'm overlooking something, I usually do.

[Licensed to kill]

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Originally Posted by GB SISSON

Search my thread from a year or two ago called 'Light in the Lifters'. There was a lot of good info added by experienced barners. I showed a quasi-scientific method to check if the lifter's thread was tight enough to hold in service, aided by guys way smarter than me. EDIT: 'Loose in the lifters'

I checked that thread out. Lots of good info regarding the tension on the adjusting screw. Thanks for the heads up.