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#101
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So I missed the final step to locking the polylocks. Didn't turn the nut after tightening the set screw. That's why I had one loosen up after the cam break in. Thought I just forgot to tighten the screw on that one. But the locks weren't set. Now I need to go back in and tighten them right. Thanks again Clay. You are a big help.
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#102
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Yup, glad you caught that. The polylock nut/setscrew needs to be tightened together to properly lock against the top of the rocker stud. 1/2 turn on a 7/16 stud is usually .050" of preload, which should be good unless they are short travel lifters.
I usually set the 1/2 turn, then tighten the setscrew lightly against the stud. Then turn the box wrench and allen wrench together. Usually ends up a little more than 1/2 turn of preload once you cinch it all down.
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I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
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#103
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I went back over all of the rockers and it doesn't seem like any backed off yet.
One thing I noticed while I was setting the half turn preload was that some of the lifters depressed a lot easier than others. Is it that some were pumped up and some had bled down? Is this normal or did I find a problem? |
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#104
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Half turn is correct for a BBC "WITH" 1.7 ratio rocker arms.
While your heads do have BBC size studs...You do not have 1.7 rockers. So 1/2 turn may not get preload to manufacturers minimum spec. At zero lash (no slack at all) the pushrod will be just a little harder to spin with your fingers. Feeling for up/down is way before you get to zero lash. Need these lifters preload specs. Then measure the first valve adjustment to see how much turn it takes to get preload right where you want it. Then you can just do the turn thing on the rest of the valves. With preload set with less than the minimum spec...You could easily have clickety click valve noise. That clickety click is hard on all your valve train components. And just barely finger tight with the set screw so the nut can turn and lock it down. Little more preload is better than not enough. Clay |
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#105
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Quote:
Plunger cups usually hold enough oil to refill the bottom of the lifter a time or two. Some plungers have a spring loaded check valve while others have a floating check valve. If the lifter is full of oil, spring loaded valves will hold when you push down on the plunger. Floating valve on the plunger, you have to push down really fast for the plunger to hold. Pushing really slow will let the plunger bottom out in the lifter. Bad or defect valve on the plunger are lifters that go clack clack loud. Bleed down rate by brand and type is a another story. Clay |
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#106
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In post #100 you say the instructions said to "rotate until intake opens then set exhaust". You sure it didn't say to "rotate until intake opens then continue rotating until intake is almost closed then set accompanying exhaust preload"? That's what instructions for all I've ever done said. Not continuing to rotate until intake is almost closed exhaust may have not been quite on base circle and be the source of your light clacking (not quite enough preload). I don't know, just a thought.
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#107
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EO - IC method.
The exhaust opens BBDC The intake closes ABDC At intake opens neither lobe will be on the base circle. |
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#108
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Quote:
I'll go back over it and make sure the intake valve is closing when I set the exhaust. |
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#109
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Not 'rotate until intake valve has opened, and then almost closed' ?
I'm betting you used new lifters. Would you have happened to clean them? If not, that could be part of your 'tick' problem, the packaging lube can harden and make them 'lazy'. Best to always disassemble and clean them before use. You can run some mild detergent like Marvel Mystery Oil, and in time, it will loosen that stuff up. Just a suggestion. .
__________________
. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
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#110
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Comp Cams version of adjustment:
http://www.compcams.com/technical/in.../comp4-116.pdf Excerpt: "Begin by rotating the engine over again until the intake valve reaches maximum lift and is almost all the way back down. Then set the exhaust valve using the same method as the intake (.030” to .040”, or ½ to ¾ a turn of the wrench past zero)." .
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. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
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#111
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HWTSTR55 Isn't that what I posted above and you said NO?
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#112
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As said above.
Exhaust just opening - do Intake Intake just about close - do Exhaust One problem though especially if lifters weren't soaked in oil to fill the lifter, when rotating the engine to adjust valves, the lifter was not pumped up. If it was adjusted with the lifter half collapsed (bled off), the valves would be way off. (adjusted too tight and hard to start or run/idle with backfiring probably) I usually fine tune with engine running to keep the lifters pumped up. (messy though without special precautions)
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John Wallace - johnta1 Pontiac Power RULES !!! www.wallaceracing.com Winner of Top Class at Pontiac Nationals, 2004 Cordova Winner of Quick 16 At Ames 2004 Pontiac Tripower Nats KRE's MR-1 - 1st 5 second Pontiac block ever! W.E.C moment "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." "People demand freedom of speech to make up for the freedom of thought which they avoid." – Socrates |
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#113
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Quote:
Rocker stud size and rocker ratio will change preload a bunch. 1/2 to 3/4 is factory BBC directions for 7/16ths studs and 1.7 ratio rockers. Need the OP's lifter specs for preload. Then measure one to see what turn is needed to get it right. Rest can be done by turn amount after that. Clay |
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#114
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Quote:
"If your adjuster nut is 7/16 x 20 threads per inch, then divide 1 inch by 20 threads per inch. One complete turn down on a 7/16 by 20 adjuster nut will move .050"." So, in general, HFT lifters require between .030-.060 preload. 1/2 a turn would be .025, and 3/4 would be .0375, well within the required range, without going to far. You could go all the way to 1 full turn for .050, and again, would be within the required range. Doesn't matter what kind of rocker you have, from the stud to the pushrod on the rocker isn't where the ratio is changed for 1.5 to 1.65 or 1.7, it's towards the spring side the ratio changes. 69 Limelight - Yes, that is what you posted, but my comment was to TAQuest: "Rotate the engine again until the intake valve has fully opened. Now you can adjust the exhaust valve to zero lash, then 1/2 more turn." Which was posted in response to your comment. The difference, which we both caught, was that the adjustment was made at the point the intake was fully open, not 'almost all the way closed'. And that was what I was trying to point out. (as others were as well) TAQuest, I suggest you go back over the exhaust adjustments. .
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. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
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#115
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Went back over all the adjustments and they were within range. It's fairly easy to tell when you are compressing the lifter plunger, pumped up or not. Pumped up is easier. Some were pumped up from rolling it over, some weren't. You get a feel for where the lifter plunger travel is and then make sure you are just inside the travel range. I didn't find any reason for the valve noise.
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#116
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Witness marks on top of the rockers. Not sure if they are from my wrench or how else they would get there. See pic link below;
https://share.icloud.com/photos/0GA-...r_Township,_MI |
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#117
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#118
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A good part to help out with valve adjustments is to add a Ford type starter solenoid with the push-button option. They are around $15-25 on line, someone may be able to provide a link to one. I buy mine at NAPA locally.
I did this decades ago on the Ventura and it allows one person valve adjustments and very easy to "bump" the engine around to get it right where you want it for each rocker. I've been using the intake all the way open/set the exhaust and exhaust just starts to open set the intake method for making valve adjustments dating clear back to the 1970's. For hydraulic lifter set-ups, especially with the vast array of parts we have today it is best to measure the available pre-load in your lifters during the engine building process. A much regurgitated method to adjust is to simply determine zero lash and go an additional 1/4 to 1/2 a turn. I've found in recent years that it is best to bottom the plungers completely out when doing this on the engine stand then back them up to establish plunger distance in the middle of it's travel range. This accomplishes two things, it makes sure something wasn't hanging up someplace as the rockers got tightened down and takes the "feel" of trying to determine zero lash with lifters that aren't pump-up out of the equation. There will be no doubt in anyone's mind when you bottom out a plunger as the pushrods instantly become impossible to turn by hand and easy is you just nudge the adjusters back just a tad. At this point you can predict exact plunger placement in the lifters by simply backing them all up the same distance or number of turns. With the quality control of lifters these days and plunger to body clearances/leak down rates all over the place it also works out better if you have the plungers deeper in the lifter bodies than shallow. In theory it really shouldn't matter, but if you are like me I can't buy a complete set of hydraulic lifters where I don't get at least one "ticker" in the bunch on a hot engine if they are set about 1/2 turn or so down from zero lash. In the past 15 years or so I've been spending more time in that area when engine building and have found that lifters, especially HR's have underwent some changes to available plunger travel and how strong the spring is under the plungers. Most that show up these days will be shorter travel and stronger spring as a general rule. Anyhow, I would recommend to folks building an engine to make sure you are well on the base circle, either following TDC on your marked balancer or use the intake open/exhaust just starting to open deal and follow things around while you turn the engine. Use a magic marker to mark each rocker when finished to avoid confusion. My current engine runs a "tight lash" set-up or "hybrid" running Crower HIPPO lifters on a HR camshaft. I've been setting them at .005" dead cold and they grow about .002-.003" or so fully heat soaked. Some throw rocks at this set-up but mine has been flawless since 2009 and the quietest engine I've ever had under the hood of any car when it comes to valve train noise. It also takes the hydraulic lifter action OUT of the equation. This engine will rev right past 6000 rpms so quick you can't move the shifter fast enough to get it shifter before 6500rpm's. My previous HR cammed engine started showing signs of lifter "pump-up" around 5800rpm's and I've seen many HR Pontiac engines start to go South on the dyno about the same place. Not really a big deal since we typically cam for and shoot for peak power about 5500-5800rpms........Cliff
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#119
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Quote:
I found that once you adjust the same set of lifters with the same cam about 6 times (on the same engine) you are very familiar with the base circle and the plunger travel range. I'm fairly certain the valve sounds were not attributed to errors in adjusting the lifters. So I need to think of what else it could be. Any ideas? |
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#120
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Post some pictures of your rocker to valve alignment open and closed, clear and well lit, from a few angles.Closed is the area of most interest.
Then Run a pattern on the valve tip and post up a pic with rocker off. |
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