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valve adjustment solid lifters


Guest Gil Dobson
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Guest Gil Dobson

Motor's Manual states to obtain a road operating clearance of .015 ( hot ) you must use a .017 gauge checked against .018 which shouldn't go.

The tune up spec clearly states that .015 is the tappet clearance which I set with a warmed up running car--a fairly loose .015..Did I blow it and is this popular manual right on ?

thank you,

Gil Dobson

53 Buick Special 48D

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Guest Jim_Edwards
Motor's Manual states to obtain a road operating clearance of .015 ( hot ) you must use a .017 gauge checked against .018 which shouldn't go.

The tune up spec clearly states that .015 is the tappet clearance which I set with a warmed up running car--a fairly loose .015..Did I blow it and is this popular manual right on ?

thank you,

Gil Dobson

53 Buick Special 48D

Gil what engine have you put the solid lifters into? Are they common lifters or are they roller lifters. The specs in Motors will be for the type of lifter originally in the engine and may not be proper for adjusting rockers for solid lifters or either variety of roller lifter.

There is an inherent problem with getting adjustment for solid lifters too tight using specs for hydraulic lifters not the least of which is abnormal wearing of cam lobes. It is usually a good idea to use a cam designed for use with solid lifters as they will be harder than typical production cams for use with hydraulic lifters.

Edited by Jim_Edwards (see edit history)
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Motor's Manual states to obtain a road operating clearance of .015 ( hot ) you must use a .017 gauge checked against .018 which shouldn't go.

The tune up spec clearly states that .015 is the tappet clearance which I set with a warmed up running car--a fairly loose .015..Did I blow it and is this popular manual right on ?

thank you,

Gil Dobson

53 Buick Special 48D

________________________________________________________________

I set my valves exactly how the manufacturer says. The feeler gauge I use for setting valve adjustment is about fifteen inches long ( this is not a go-no go gauge ) at .004'" and .006" thick for VW & Porsches. With these long feeler gauges it's easy to tell proper clearance because when you have the proper clearance the feeler gauge makes a sound like someone playing one of those large saws with a bow.

BTW, in high school or college auto shop , if any one of my instructors saw someone using a crescent wrench or go-no go gauges or using a screwdriver as a pry bar they were in big trouble.

Don

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Guest Gil Dobson

Jeff,

I finally paid attention to motor's manual and figured out why they suggest that you use .017 clearance checked against .018 which should not go.. It's almost foolproof and the vehicle never ran better since I rebuilt it years ago. sometimes too many opinions can be too much ..

Thanks so much for your reply and also I can see why you might want to lower idle speed

Take care,

Gil

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Good heavens . . . setting solid lifter valve lash with the engine running??? Even at low rpm?? Never heard of that, with all due respect.

Solid tappets have "clearance", hydraulic tappets have "preload" of some amount. Two DIFFERENT things all together, with all due respect.

In setting valves for solid valve lifters/tappets, the shadetree method my associates always used was "Intake open, set exhaust" "Exhaust open, set intake", or something to that effect. KEY thing was that the valve being set was on the backside of the lobe from where the lift is. Whether you follow the firing order is not important, though, but can be done if desired. This is also the most bullet-proof method to ensure that the valve being set in not on the edge of the clearance ramp at the start of the lobe's "valve lift" section.

The first .006" of lobe lift is to gently allow the clearance (or valve lash) to be taken up before real lift begins. Seems like it is .006" on intake and .008" on exhaust? But there is a clearance ramp built into the basic lobe shape to help decrease the clearance adjusted-into the solid lifter valve train.

Hydraulic lifters (and camshafts designed for such lifters) can have similar acceleration ramps, but there should be no "lash" in those systems as hydraulic valve systems generally operate with adjustments of 1 turn preload from zero lash (factory recommendations). Over the years, higher performance seekers found they could decrease the factory-recommended preload for higher rpm capabilities, either by using less preload on the rocker arm adjustment or installing shims under the rocker arm pivots, but not by decreasing preload until valve tappet noise occurs.

In some respects, the solid lifter's valve lash can be a tuning aid. More lash effectively shortens the lobe's "open" duration and valve lift, to give a little better lower rpm performance. Tightening things up a little can do just the opposite, as long as there's still some lash in the system. Then, after the research has been done, you can get a cam ground to something closer to the de-lashed specs and still have the necessary valve lash for quiet performance when the engine's warm.

Just some thoughts,

NTX5467

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Guest steve283

I think I understand the lifter while running,my grandpaw used to do this.When asked he said he always done it this way,and this started in the 20's.He set them by the sound,back then He did not know anything about gauges and torque wrenches.he set timing by ear also.never saw any problems with his work...just sayin'

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Good heavens . . . setting solid lifter valve lash with the engine running??? Even at low rpm?? Never heard of that, with all due respect.,

NTX5467

I've done it and seen it done many, many times. I still have a set of deflectors to keep the oil from flying all over the place while setting the lash on a Chevy
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I adjust the valves with the motor running,run it for a couple miles and set the idle lower and its usually no problem. This is the only way I can do it on the 235 that is in my 37 Chevy or I will have a couple still making too much noise.

__________________________________________________________________

Chevy has a cold lifter adjustment which is the best way to get a uniform adjustment if you are not adjusting while running the engine. VW, Porsche, Nissan/Datsun, Flathead Pontiac/Olds etc. only recommend a stone cold adjustment and of course all OHC engines are stone cold. No Go gauges are for the uninitiated in the automotive trade.

D.

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Good heavens . . . setting solid lifter valve lash with the engine running??? Even at low rpm?? Never heard of that, with all due respect.

Solid tappets have "clearance", hydraulic tappets have "preload" of some amount. Two DIFFERENT things all together, with all due respect.

In setting valves for solid valve lifters/tappets, the shadetree method my associates always used was "Intake open, set exhaust" "Exhaust open, set intake", or something to that effect. KEY thing was that the valve being set was on the backside of the lobe from where the lift is. Whether you follow the firing order is not important, though, but can be done if desired. This is also the most bullet-proof method to ensure that the valve being set in not on the edge of the clearance ramp at the start of the lobe's "valve lift" section.

_________________________________________________________________ Couldn't agree more, but I have a Video of the 1962 Darlington 500 race. In the tape it shows the prep going on in the pits before the race and darn if there isn't a guy setting valves on a Ford FE 406 incher with the engine running. I have seen it done at college too-makes you wonder with all that pounding after eight cylinders that the feeler which was .014" is now .010" !!

Don

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Guest steve283

I was told by Grandpa that you tighten down just till tapping stops and back off 1/8 turn,got me thinking that if the thread size is 1/2-32 then it works out to around .014-.016...aprox...hummmm

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I was told by Grandpa that you tighten down just till tapping stops and back off 1/8 turn,got me thinking that if the thread size is 1/2-32 then it works out to around .014-.016...aprox...hummmm

------------------------------------------------------------------------

This ones even better than the No-go gauges!

Don

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Guest De Soto Frank

I tried setting the overhead valves in one of my vehicles ( Falcon or Stovebolt Chevy) with the engine running, and it peened the be-jeezus out of the feeler-gauge... never tried it again...

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I was told by Grandpa that you tighten down just till tapping stops and back off 1/8 turn,got me thinking that if the thread size is 1/2-32 then it works out to around .014-.016...aprox...hummmm

I like that idea for solid lifters!

For hydraulic lifters, you can do similar, but tighten it by 1/8 to 1/4 turn from "noise just stops".

Enjoy!

NTX5467

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I was told by Grandpa that you tighten down just till tapping stops and back off 1/8 turn,got me thinking that if the thread size is 1/2-32 then it works out to around .014-.016...aprox...hummmm

It seems to me that on a 1/2-32 thread one complete turn would be about .031" so 1/8 of a turn would only be about .004"

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Guest steve283

if you have a 32 handy check it i did the math before i stated it,its .09 to .12 in real terms.but i was ball parking it at what 1/8 turn was. probably should have been exact,but i was trying to make a funny using a tried method.for that i am sorry.

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if you have a 32 handy check it i did the math before i stated it,its .09 to .12 in real terms.but i was ball parking it at what 1/8 turn was. probably should have been exact,but i was trying to make a funny using a tried method.for that i am sorry.

Maybe we're not talking about the same thing but 32 is the threads per inch. Divide 32 into 1000 you get a little over 31(thousandths) per thread so turning a nut one eighth would move it a little less than .04. I'm a retired electrician. One Time I was installing some switchgear and a contact had to be adjusted around .017 closer than it was. Nobody had a micrometer. I got a 1/4-20 nut and bolt. I figured each thread is .050 so each facet is a little over .008. I snugged the nut down and put a mark at the high point. Then I screwed it in till I could move the nut through 2 sixths. Not precise but close enough.

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I've done it and seen it done many, many times. I still have a set of deflectors to keep the oil from flying all over the place while setting the lash on a Chevy

Chrysler solid lifters require adjustment while running on my 273 V8. It's messy, but you can sure hear the tic tic tic go away as you adjust. I am going to take some extra valve covers I have and cut a gaping hole in the tops so as to be able to adjust without such a mess on the exhaust manifolds.

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