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| Rod Side Play; Out of spec. side clearance | |
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| Tweet Topic Started: Sep 4 2013, 01:54 PM (2,283 Views) | |
| MoonRaker | Sep 4 2013, 01:54 PM Post #1 |
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My service manual shows a connecting rod side play specification of .004-.010. #3 connecting is .013 and #2 is .015 Will an F-134 tolerate the large out of spec clearance or will there by an issue with rod slap? According to Hastings Piston Rings if you have excessive/out of spec crankshaft end play it will cause the piston rings to spin. I wonder does rod side play have the same effect thus the .004-.010 call out. I've contacted Scott at Ohio Crank where the work was done and he said he doesn't see a problem unless this engine cannot tolerate the excessive rod side play clearance. Any comments would be welcomed before I yank out the crank and install a backup unit. |
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| spm1us | Sep 4 2013, 05:47 PM Post #2 |
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FYI, the rings are supposed to spin unless they are a "pinned" design as found on some 2 strokes to avoid catching an end gap in the 2 stroke ports. Excessive bearing clearance and side clearance will cause low oil pressure and can cause the oil to be diverted from other areas in the engine. Oil, like any other fluid, will always take the path of least resistance - the excess clearance is not very good for the rod alignment and can cause strain on the crankshaft journal and wrist pin. The Willys rods are not particularly beefy to begin with and in conjunction with the long stroke can fail. The Willys engine is not designed for sustained high RPM use combined with the slot cut into the rod's factory I-beam design is a recipe for problems. I would try and find a suitable substitute - have it magnafluxed for cracks, try to match the weight or balance to match the other engine components and have the big end/small end/rod length checked/resized. You can check the substitutes, with a dial caliper, for width prior to expending any time/resources on them - also check the weight to see how close they are to existing #3 rod. I hope this helps - don't shortcut your rebuild now over a con rod replacement. Good luck, Sam Michael Jr, Jax, FL |
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| MoonRaker | Sep 4 2013, 06:26 PM Post #3 |
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Oh! So Hastings Piston Rings is incorrect? I don't think so, rings rotate,but not very much. There is a purpose for following a ring manufacturers ring installation spacing instructions. Below is from Hastings (P79-87) { Crankshaft end play also can affect oil control. If end play is excessive the back and forth movement also moves the pistons in the cylinders causing rings to "spin". This affects their ability to control oil and causes excessive side wear.} I would like to solicit answers regarding others who have assembled an F-134 with greater connecting rod end play than spec. What was the outcome? |
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| oldtime | Sep 4 2013, 07:17 PM Post #4 |
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Myself I have not assembled any Willys 134 conecting rods out of specification. It's slightly out of specification but I believe that the engine will be O.K. with .013 and .015 rod side play. As you know a Willys crankshaft has a very strong forged design and so it has absolutely no effect on the crankshaft journals. Rod side play is limited in order to keep the connecting rods out away from the front and rear of the piston wrist pin journals. If you look you can easily see that ample clearance is available. The rods do not necissarily run near true centerline of the bore anyway. The rods just simply need to clear the sides of the piston journals. If the rods migrate fore/aft that's O.K. as long as the rod bearings and wrist pins are tight My favorite machinist is pushing 80 years old and still runs his own machine shop by himself ever since the mid 1950's. I asked Dave about this same concern once before. His reply was that many hot rodders intentionally grind down the connecting rod journal sides to allow increased rod float. Piston rings should be set according to Willys instruction so that upper and lower compression rings do not align vertically at the gap. Verticle alighnment of the ring gap can only serve to reduce cylinder compression. Follow Willys instuctions unless different than the piston ring manufacturer. |
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Currently building my final F-134 powered 3B . Rock Crawler using factory parts from the Willys Motors era (1953-1963) http://s4.zetaboards.com/CJ3B_Bulletin_Board/topic/30228766/1/#new | |
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| MoonRaker | Sep 4 2013, 08:54 PM Post #5 |
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Thank You, Ken When I had Scott on the phone he said they run a lot of there builds with way more clearance, but he also said they did not specialize in this particular engine. The ring install sheet from Hastings showed the staggered arrangement with the top 2 compression ring gaps 180 apart. There is reasonable wrist pin clearance looking down into the pistons but not perfect 50/50 split symmetry. I put a call in to Dawn Hill at Hastings to see if they have any ruling on rod side clearance and effects on rings. Remember I've had to learn AERA TB-2025 the hard way. There ain't gonna be no third time. Dennis |
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| spm1us | Sep 5 2013, 05:28 AM Post #6 |
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It's immaterial to me, but piston rings are DESIGNED to spin ALL the time if the cylinder is honed correctly and has the proper RMa finish and Cross Hatch angle. That's what keeps the ring grooves clean and prevents "stuck/carbonized" rings. Along with preventing blow-by, that's also why you offset the ring gaps 180 initially upon installation - the gaps rotate ALL the time - I know you're becoming proficient at tearing down this engine - mark the underside of the pistons and compare the gap locations on your next/subsequent tear-down. Do you have any idea what the RMa finish and Cross Hatch angle is in your cylinders? What stones and grit did your machinist use to finish your cylinders? Did he "bottle brush" or "soft-hone" the bores? Did the machinist use a CK-10 or similar machine or did he use a drill motor? Are you using Moly or Cast Iron rings - they each take a different cylinder wall finish. Did you scrub the block/cylinders with steaming hot water and Dawn dishwashing detergent? Did you scrub the cylinder walls with ATF and paper towels until the lint-free paper towels came out clean? Did you specify the piston to wall clearance to the machinist - did he tell you the clearances? Did you check and verify the ring gaps to set the correct clearance? Did you check the bearing clearances or at least "plasti-gauge" the bearings? Did you "mock" up the motor to check everything prior to final assembly? Did you record the part numbers and ALL clearances on this build? Did you check the crankshaft end-play with a dial indicator? You believe whoever/whatever you want - I know how to build engines and have spent the better part of my younger years in one of the best machine shops in NE FL with one of the best race engine builders teaching me. I strive to learn something each and every day. The reason they open up the side clearance is to get more oil flow to the rod bearings, add additional cooling to the crank journal and reduce friction for high RPM use. This can also create an additional problem of putting too much oil on the cylinder walls and the rings have a hard time with oil control. At the same time, you also restrict the oil flow to the upper end to keep the oil at the rotating assembly. It's an old circle track and drag engine trick along with reversing the pistons to take advantage of the offset in the wrist pin bores. If you read the instructions you mentioned AND comprehend their meaning, Hastings is referring to CRANKSHAFT END PLAY(fore and aft) - NOT Rod Clearance! These L and F-head engines already have a poor oiling system known for starving the #1 main bearing, but OK, you can bleed some desperately needed oil through excess rod side clearances. It's your money and time, we are all just trying to help each other here on the 3B site. Pick and choose whatever information you deem worthy - hopefully you won't be repeating this process again. BTW, I've built a number of F-head engines and I don't/won't build them incorrectly(w/ excessive clearances/out-of spec) - it's easier to "blueprint" the engine from the start and not go through what you are experiencing, but I guess you already know that, too. |
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| MoonRaker | Sep 5 2013, 08:11 AM Post #7 |
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Hey Ken, Do me a favor and delist/remove me from this site. I'm out of here. Take Care |
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| oldtime | Sep 5 2013, 06:26 PM Post #8 |
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Dennis, I will do as you ask but I first I ask you to please reconsider your request before ending commumication with this board. I know all board members would hate to loose you, a contributor in good standing. I am certainly not here to dictate and others opinions are welcome. Take wanted advice wherever you can find it and leave any remaining unwanted opinions to see if they can survive the test of time. Thanks, KEN |
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Currently building my final F-134 powered 3B . Rock Crawler using factory parts from the Willys Motors era (1953-1963) http://s4.zetaboards.com/CJ3B_Bulletin_Board/topic/30228766/1/#new | |
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| MoonRaker | Sep 5 2013, 07:46 PM Post #9 |
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Hi Ken, I respect that call. I think I may have some information that might help. With that said; Sammy, you need to understand "I ain't no shoe shine boy". Another malevolent diatribe on this subject, I've gotta split. Blowing down a guy just isn't cool. I don't get whether I'm being called out or getting punked. If I'm getting called out, well then, I've got a deal. Sam it's in your court. Dennis |
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| oldtime | Sep 5 2013, 08:00 PM Post #10 |
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Be calm Dennis, There is way too much tension in the world as it is. And it's apparent that your near to your personal limit. Sam works at rebuilding various engines all the time and therefore he is very opinionative. (AKA set in his ways) But the final authority here is not any one of us members, it's Willys Motors Inc. And that's my position to intervene in there absence. Please realize that we're proud to have both you and Sam as members. So just see things for what they are and remain calm. Thanks, KEN |
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Currently building my final F-134 powered 3B . Rock Crawler using factory parts from the Willys Motors era (1953-1963) http://s4.zetaboards.com/CJ3B_Bulletin_Board/topic/30228766/1/#new | |
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| MoonRaker | Sep 5 2013, 09:37 PM Post #11 |
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Ken, I've got a weird idea, Sam likes building engines and doing blueprint work, bespeaks of being a final authority. So lets let an engine dyno test be the final authority. Here's a thought; 1 year to build. You pick a local facility with an engine dynamometer, act as a referee. The rules, lets make'em simple. Any 938 for carburetion, no carb spacers, no headers. Normally aspirated only, no blowers, no turbos, no juice. Must run a stock distributor housing, electronics okay. 6V or 12V no problem. Nothing over .080 over bore. No chicken stuff like dump an engine core off to Alan Johnson, Nickens Brothers etc, for some "lite massaging". Loser pays for the dyno time, eats crow, preforms a formal act of contrition, shunning is deployed. I n other words, losing ain't good. Winner, best pull out of 5 each. I'm up too it. I think it's fair, put up or shut up. Whats learned out of these builds could have a desired effect in the long term on what works, what doesn't. Share the info with all, have Derek put it on the main page AKA: The F-134 shoot out. May the best builder win. Heck, they do sanctioned barbeque contest all the time, why not contest a goofy old jeep engine? Dennis |
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| spm1us | Sep 6 2013, 05:46 AM Post #12 |
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Dennis, it was neither my intent nor objective to embarrass or humiliate you. If I offended you I apologize. I was trying to answer your request for information on connecting rod side play. I claim no status as "Final Authority". I try to learn each and every day. Rather than expending any more time and energy debating each and every point of the posts, I would rather wish you Good Luck with your project, Sam Michael Jr, Jax, FL |
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| oldtime | Sep 6 2013, 04:18 PM Post #13 |
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O.K. let's get this topic back on track. I forgot to mention that I do currently have an engine that I recently rebuilt. Everything now is back to stock standard excepting the cylinder bores which are .030 O.S. All replaced components are genuine OEM NOS. So it's in great shape now but read on ....... When I took that engine apart it apparently had never been bored out. Upon dis-assembly everything looked perfectly normal except that the crankshaft had excesive end play and the rod journals had excess play. Seems like the crankshaft was at .020 end play or something like that. But I do recall that the rod play was as high as .035". There's just about no way to determine if the crankshaft was previously worked on or not. The crankshaft journals and mains were all at standard diameter when taken apart. I suppose that it t could have been welded up and ground back to standard but that does not seem normal. Anyway the point is that this particular engine showed no other abnormalities besides normal wear of the bores and valve seats. In my mind there are only two things that can cause excess rod side play. Either the connecting rods have been narrowed or the rod journals have been widened. As you know whenever a crankshaft is ground to undersize dimensions the operator must be very carefull not to grind on the cheeks of the crankshaft journals. Also if the connecting rods are re-sized then they should not have the sides re-surfaced. Those two conditions will surely increase rod side play. |
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Currently building my final F-134 powered 3B . Rock Crawler using factory parts from the Willys Motors era (1953-1963) http://s4.zetaboards.com/CJ3B_Bulletin_Board/topic/30228766/1/#new | |
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| MoonRaker | Sep 7 2013, 07:14 PM Post #14 |
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Epilogue: ( I think this was the last sequence in the show F.B.I.) I am going to employ, in the infamous words of Bob Uecker "just a little outside". Putting this engine together with #2 and #3 rod side clearance just a little out of spec. .013 on #2 and .015 on #3. If this engine locks up, spits out the crank shaft or becomes the Rio Grande County vector control unit, I will offer equal halves of my Jeep shop to you Sam and Ken at fire sale prices. In other words if this don't make it, I am going out of business. Stay tuned for the next exciting episode---Can Dennis Get His 3B Down the Road Without it Being Towed Back Home. (Going 1.5 miles before the crank locks up twice is like a vacuum cleaner-----it sucks) Thanks Sam, Ken, Dennis I'll keep you posted.http://i4.ifrm.com/style_images/1/icon1.gif |
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| oldtime | Sep 8 2013, 02:44 PM Post #15 |
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If I recall correctly the first installed crankshaft locked up from a defective rear main seal. So what caused the second crankshaft to lock up ? Ken |
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Currently building my final F-134 powered 3B . Rock Crawler using factory parts from the Willys Motors era (1953-1963) http://s4.zetaboards.com/CJ3B_Bulletin_Board/topic/30228766/1/#new | |
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