jakeshoe Posted April 9, 2006 Share Posted April 9, 2006 Bill, Go back and re-read what I posted about the plastic checker.... It is marginal at best... First you need to figure out what your bind was. Did the engine rotate OK with just the lower end assembled? Now that you have the heads on and are checking it could be a piston to valve clearance issue, retainer to guide, valve spring coil bind, rocker to retainer issue, etc. Better sort that out first. What is your combo? Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 9, 2006 Share Posted April 9, 2006 I got that the plastic checker is marginal, just using it as a reference in my findings yesterday. Engine rotates perfectly as a shortblock and with heads installed. Bind came when I installed the rocker arms on the #1 cyl. These clearance issues come from several different reasons right? I'll look around this morning on how to check them and what to look for. Block has to be stock deck height, this is it's first rebuild and I didn't have it decked. Heasds are alum performer RPM that have been gasket matched, but other than that I can't tell if any components are not part of what comes w/ them. They are brand new and have never been run. Stock Crank, Summitt rods, summit flat top pistons w/ valve reliefs. I'll keep you posted. Looks like i might need to start another thread? Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted April 9, 2006 Share Posted April 9, 2006 ok' date=' orderd my rocker arms and an adjustable length pushrod last night. Today, was messing around, and thought I'd cut one of my pushrods and try to make one myself anyway right? WRONG. Those are made out of some hard stuff!!! Ruined the first 3 threads on one of my taps. The hole in the pushrod was allready too big for the one I was using. So I figured i'd drill it out a bit and the drill just burnt up. So I'll be looking for the one coming in the mail... Thought I'd see what wear pattern the 7.800 rods would put on my valve tips so I, marked the valve tips, took the slack out of the stock rockers, and got the engine about a half a rotation and it felt like there was bind! I was moving slow and didn't force it at all. I then backed off the bind, pulled the rockers and looked at the marks that had been left so far. The wear mark on the left (Exhaust valve) tip was almost un-readable, the wear mark on the right tip (Intake valve) looked like a full sweep and was on the high side of center which would read as a short push rod right? SO going back to my earlier "plastic checker" lengths there was a ~.063 gap between the tool and the VALVE tip, and ~.093 on the exhaust tip (gap in same place, between the checker and the valve tip). Both telling me to get shorter push rods, so would what I ran into be bind or was I just being timid? I'm kind of freaking out. Any thoughts? When i get my rocker arms and adjustable rod I'm guessing I should start way short and progress to a center mark on the valve tip for both valves correct? I read through all your links grumpy, thanks. I feel like I'm learning and I get the theory side but I'm confused as to why the mark was on the high side of center and the plasic checker measured the current rods to be too long?[/quote'] Yup, they are hard, supposed to be, and this is why I used a welder, two nuts and a machine machine screw cut off! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 10, 2006 Share Posted April 10, 2006 Ok, well, i was being TIMID! It was really bugging me that the motor was 'binding' but i just couldn't wait untill the adjustible checker came in to mess w/ it again. I read a bunch Sun. morning and thought about it. So I tried doing it again, slowly, w/ just one rocker installed. Watching the spring, and the piston and the valve and got it to rotate freely w/ ONE rocker set at a time. Then it hit me..... Ever feel releif AND like the biggest Dumb A** in the world at the same time? The lobe overlap is what I hit, both valve springs pushing agains me instead of just one......... So how come none of you guys let me off the hook!!! I took some pics of the wipe, looks like the p-rods are a bit short, i'll post the pics durring lunch. What a relief!!! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 10, 2006 Share Posted April 10, 2006 here's the wipe on cyl 1, two full rotations each cam lobe. Exhaust on the left got smudged a bit but looks like it's crooked (maybe the valve rotated?). One on the right looks short, at 7.8". So once the adjustable P-Rod and roller rockers come in, I'll do it again and get my P-Rods ordered. I'm thinking the Roller rockers won't mark as well, any tips, hints? Thanks guys. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted April 10, 2006 Author Share Posted April 10, 2006 BillZ260 even if you never get that valve train EXACTLY correct Ill point out two things here (1) you take GREAT CLEAR PHOTOS (2)getting your valve train geometry exactly perfect is NOT CRITICAL, ON A HYDROLIC LIFTER ENGINE RUNNING UNDER 6500,RPM, BUT GETTING IT DAMN CLOSE TO EXACTLY CORRECT IS, don,t get crazy, just work with it untill your sure its very close to the ideal specs, haveing pushrods that are lets say 20-40 thousands too long or short won,t matter on most street engines,simply because the stock production engines rarely get that close to ideal specs and theres generally a minimum of .050-.070 thousands slack in a hydrolic lifter seat between fully pumped up and fully depressed I think sometimes guys go off, and loose sight of the big picture,parts wear, machinist get things close but never exact! yes you want to minimize the variations but just think it thru, do a good job and don,t loose sleep over things that you really can,t control to the last few ten thousanths of an inch! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 11, 2006 Share Posted April 11, 2006 Thanks! I took about 10 picks of them total playing w/ settings, flash and light before I got a few that actually turned out. I'm excited about getting the adjustible push rod and playing w/ getting the length closer. This whole thing is a learning thing for me and it's fun. (As long as I don't think my engine is binding! lol ) I'm a machinist by trade and after reading up on all the articles you posted plus some, I didn't feel comfortable w/ using what I had. I'll post more pis when I get the new rollers and adjustable cranked on the engine. Any tips on making the roller show up well on the valve tips??? Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted April 11, 2006 Author Share Posted April 11, 2006 "Any tips on making the roller show up well on the valve tips???' well personally I don,t use a majic marker.... but something you probably use frequently, simply because it tends to work better http://www.tools-for-woodworking.com/browseproducts/Starrett-Machinist's-Blue-Dye--4-oz..HTML Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted April 11, 2006 Share Posted April 11, 2006 grumpy, we just need a port to connect to your brain and download information, what's the possibility of getting that done? Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted April 11, 2006 Share Posted April 11, 2006 The roller rockers will show up on the valve fine, very clear... Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 11, 2006 Share Posted April 11, 2006 I might have some of that layout dye hidden away somewhere. If i have trouble w/ the marker then I'll pick some up at the wholesale tool store or maybe I can borrow some from work. Yes, how much would every one need to chip in to get that procedure done for Grumpy? Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 13, 2006 Share Posted April 13, 2006 Ok, got my adjustable rod in today. I set it to 7.850 (.050 longer thans what I tested with originally). Here is the results. I think they are alot closer than with 7.8" rods. What do you all think? To me it looks like they are a hair too long but unless I get custom rods, I think this is it. I'll run a couple more cyls tomorrow and see what turns up but it looks like I should be able order my rods tomorrow eve. I might call the speed shop for prices, and see if they can get them in sooner. I edited these pics a bit to try and get the wear marks to show up so the colors are off a bit. Exaust #1 cyl Intake #1 cyl Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted April 13, 2006 Author Share Posted April 13, 2006 "I set it to 7.850 (.050 longer thans what I tested with originally" go with IT! at 7.850 " its close enougth that any changes will be minor and not likely to cause problems Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted April 13, 2006 Share Posted April 13, 2006 And those pics are after rolling the motor through a revolution? It's a LITTLE too far to the outside of the valve actually indicating the pushrods are a bit long. Try it at 7.800 on the adjustable pushrod and see if you can pull it back on the valve a bit. Couple of things to watch for with roller rockers, be sure they aren't touching the retainers, and often the bottom of the rocker will rub the hex portion (or its radius transition) of the rocker stud on a SBC and it will skew the geometry test. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 13, 2006 Share Posted April 13, 2006 Well, we have comparison pics here, the earlier ar 7.8" rods (Pick w/ both valves) and the post last night was w/ it set 7.850. On both tests, I rolled the engine over 4 times to cycle each valve twice. So on the drive in this morning I was thinking. When you rotate the engine over are the lifters pumping up at all? If so, then I think the 7.850 is what I want, but if the are not pumping up then I'm thining the 7.8 would be closer to center. Couple more comments? Please. I'm off tomorrow, I can get them from the speed shop if I order today and have this thing together tomorrow!!! No rush though really, I definitly want to do it right. Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted April 13, 2006 Share Posted April 13, 2006 Well the earlier photos I thought you were using a different rocker. Check the geometry with the rocker you are using now (roller) set at 7.800, and be sure the rocker isn't rubbing against the rocker stud. The first photo shows a very wide pattern, that gets too close to the rocker stud side of the valve. The wide pattern may be because you used a stock type rocker and not that the actual motion is that far... The photo with the 7.850 shows a narrower mark which is good, but it is offset too far towards the exhaust side of the head. Ideally you want a nice narrow range of travel across the top of the valve, but very slightly off centered towards the intake side of the head. So that at the widest part of it's travel it comes to center. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 13, 2006 Share Posted April 13, 2006 good point, DOH! Sheesh. I'll see what the 7.8 does when I get home. You guy's are keeping me straight! What about how the lifter affect this test??? Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted April 13, 2006 Share Posted April 13, 2006 Bill, I use a solid in place of a hydraulic even if the motor will use hydraulics. The hyd will compress to the end of the plunger and mess with the readings. If you have a way to setup a dial indicator or a pair of calipers to measure and make sure the pushrod cup is in the same location that is good to check. Remember the hydraulic plunger will compress when adjusted, depending on how much you adjust it. On a performance motor I usually go about 1/8-1/4 turn on a hydraulic after it quits clacking on a running adjustment, and right at 1/4 turn on a static adjustment on the stand. 1 complete turn on a 3/8-24 stud is about .042" of plunger travel. If you use a hydraulic lifter specifically made for it, you can keep it at the very top of the plunger almost against the keeper, and it prevents hydraulic pump up at high rpms. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 13, 2006 Share Posted April 13, 2006 I'd say the 7.8's look like they a bit tighter pattern but aren't much closer to center. I'll go .050 shorter and see but 7.8 looks just about right to me. EDIT 7.7 looks even better, noticed that the intake and exhaust lifters differed a bit in compression but not much. I'm going w/ the 7.7 and will take pics of the finished valve train and engine this weekend if I'm lucky and post those on of my threads EDIT : 7.790 is what the shop had, figure they are close enough. If you all think that's a huge mistake, then I'll cancell. Othewise I'll have them by noon tomorrow. :) Quote Link to comment Share on other sites More sharing options...
Michael Posted April 16, 2006 Share Posted April 16, 2006 Bill, in the final iteration of pushrod length checking, how wide was the area on the valve stem swept by the rocker tip? Any pics? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.