Mister Fab Posted February 25 Share Posted February 25 (edited) Hi all, I reinstalled the crank today, with new bearings. It first was stuck and I found out that the rope seal is the problem. I can't turn the crank when the rear bolts are tighten with the correct torque. The rope seals are brand new from fel-pro rebuild kit. Has someone got any tip? I removed the crank and checked the seal several times already. Edited February 25 by Mister Fab Photo (see edit history) Link to comment Share on other sites More sharing options...
gungeey Posted February 25 Share Posted February 25 (edited) Did you torque #5 cap and check for clearance before installing the rope seal (plastigauge etc)? I oil the end of a wooden hammer handle and press the rope into its groove a "slide while exerting pressure"action. The rope seal gets assembly lube at final installation. It should addmore resistance but not lock the crank up by any means. If I'm trial fitting the crank the upper bearings get a smear of oil and the caps go on dry one at a time and tested for proper oil clearance. After that checks out then use assembly ube on 1-4, the last cap gets handled as a separate job. Even if the machine shop did this measuring I would do it again, especially final cleaning crankshaft, oil journals with brushes etc. Any debris will bite you hard. What brand of rear main seal did you get? Edited February 25 by gungeey (see edit history) 1 1 Link to comment Share on other sites More sharing options...
NTX5467 Posted February 25 Share Posted February 25 (edited) The rope seal will have more drag than a lip seal, but not enough to really drag things down. In some of the older manuals, it talked about using a round rod to seat the seal in its housing. Press and roll the rod against the seal, so it gets more into a place of how it will be with the crank installed. You might need to find an old MOTOR manual (or similar) to find the "unadmitted to" steps which the factory leaves out of their factory service manuals. NTX5467 Edited February 25 by NTX5467 (see edit history) 1 Link to comment Share on other sites More sharing options...
NTX5467 Posted February 25 Share Posted February 25 2 minutes ago, gungeey said: Did you torque #5 cap and check for clearance before installing the rope seal (plastigauge etc)? I oil the end of a wooden hammer handle and press the rope into its groove a "slide while exerting pressure" action. The rope seal gets assembly lube at final installation. It should addmore resistance but not lock the crank up by any means. If I'm trial fitting the crank the upper bearings get a smear of oil and the caps go on dry one at a time and tested for proper oil clearance. After that checks out then use assembly ube on 1-4, the last cap gets jabbering as a separate job. Even if the machine shop did this measuring I would do it again, especially final cleaning crankshaft, oil journals with brushes etc. What brand of rear main seal did you get? When reading this procedure, about leaving one bearing dry, this IS necessary as Plastigauge does not like oil. So keeping the particular journal and bearing half dry is important for an accurate width of the Plastigauge. Then, after those checks are made, as mentioned, remove the bearing cap and lube the bearing for final use. As the rope seal will need a bit of lube, too. NTX5467 Link to comment Share on other sites More sharing options...
Mister Fab Posted February 25 Author Share Posted February 25 (edited) The crank just came back from machining with 010 less, so I got+010 bearings. When I torque all the caps without the rope seal, I can turn the crank by the hand, with not too much forcing it The problem is when installing the rope. I used a round tool to preinstall it, as I saw on different tutorials, and oiled it. It comes from a gasket kit from FelPro And I used rebuild grease on all the bearings Edited February 25 by Mister Fab Modifié (see edit history) Link to comment Share on other sites More sharing options...
gungeey Posted February 25 Share Posted February 25 Should look about like this 2 1 Link to comment Share on other sites More sharing options...
Mister Fab Posted February 25 Author Share Posted February 25 On a Buick Engine group on Facebook, lot of people told me to replace by neoprene. What's your feedback on those? Link to comment Share on other sites More sharing options...
gungeey Posted February 25 Share Posted February 25 (edited) 35 minutes ago, NTX5467 said: When reading this procedure, about leaving one bearing dry, this IS necessary as Plastigauge does not like oil. So keeping the particular journal and bearing half dry is important for an accurate width of the Plastigauge. Then, after those checks are made, as mentioned, remove the bearing cap and lube the bearing for final use. As the rope seal will need a bit of lube, too. NTX5467 People tend to have their own way. Again, at mock up, I put an oil smear on upper bearing (the block side), the cap side stays dry for the plastigage. Then the crank is removed, assembly lube applied and crank again installed. I use the engine crane to cradle the crank into the block, too. No banging. Edited February 25 by gungeey (see edit history) 2 1 Link to comment Share on other sites More sharing options...
arnulfo de l.a. Posted February 25 Share Posted February 25 (edited) 10 minutes ago, gungeey said: People tend to have their own way. Again, at mock up, I put an oil smear on upper bearing (the block side), the cap side stays dry for the plastigage. Then the crank is removed, assembly lube applied and crank again installed. I use the engine crane to cradle the crank into the block, too. No banging. That is one good looking crank! Is it new or refurbished? The groove in the mains is new to me. Looks like a good idea. Edited February 25 by arnulfo de l.a. (see edit history) 1 Link to comment Share on other sites More sharing options...
gungeey Posted February 25 Share Posted February 25 1 minute ago, arnulfo de l.a. said: That is one good looking crank! Is it new or refurbished? The groove in the rod journal is new to me. Looks like a good idea. Forged steel baby 👍 That's the same one you have in your 65, Arnulfo.. pretty sure they don't make em anymore 1 Link to comment Share on other sites More sharing options...
gungeey Posted February 25 Share Posted February 25 (edited) 58 minutes ago, Mister Fab said: On a Buick Engine group on Facebook, lot of people told me to replace by neoprene. What's your feedback on those? Best makes a rope seal I like. It's called: Graphene. A little pricey, at $30, but have had good luck with them. I put a pin and centerpunch several divots for grip on the ropes groove. For the timing cover seal I use the new style neoprene upgrade as it has no seams. In the back whether it's neoprene or rope there are still two halves for potential oil leaks, correct? I see no advantage, so I stick with what's working. Edited February 25 by gungeey (see edit history) 1 2 Link to comment Share on other sites More sharing options...
JZRIV Posted February 25 Share Posted February 25 (edited) Would not use rope. The "One-piece" rear main seal in this link is what I would use. https://www.bopengineering.com/buick_v8.shtml Also if you haven't already, plastigage your rod and main bearings and record readings for a baseline. Yes it will take time but if you have have a problem when engine is started, you'll have confidence bearing clearances are not the issue. Edited February 25 by JZRIV (see edit history) 2 Link to comment Share on other sites More sharing options...
arnulfo de l.a. Posted February 26 Share Posted February 26 15 hours ago, JZRIV said: Would not use rope. The "One-piece" rear main seal in this link is what I would use. https://www.bopengineering.com/buick_v8.shtml Also if you haven't already, plastigage your rod and main bearings and record readings for a baseline. Yes it will take time but if you have have a problem when engine is started, you'll have confidence bearing clearances are not the issue. Should this be done before or after seal install or both before and after? Link to comment Share on other sites More sharing options...
NTX5467 Posted February 26 Share Posted February 26 In one respect, on the main bearings, you might put the bearings in, fully seat them, dry them of oil, then install the main caps dry with the Plastigauge. Then remove the caps and check the width of the squish of the Plastigauge for the bearing clearance. You can do all of the mains this way, then remove the crank and lube all of the bearings and install them for good. On those lubed main bearings, then rotate the crank to bring the rod journals up for installation. Dry both bearings, install the rod caps, remove the rod cap and check for squish, then oil everything and put it back together on that journal. Repeat with the other rod pairs. When done, re-check for ease of turning. It might be a bit geeky, but doing this totally dry might result in just a hair wider clearances, but still well within specs. But whether the block or rod size bearings are oiled or not, still a good way to measure things other than use an inside micrometer and a normal micrometer (and related math, as in prior times). Enjoy! NTX5467 Link to comment Share on other sites More sharing options...
arnulfo de l.a. Posted February 26 Share Posted February 26 37 minutes ago, NTX5467 said: In one respect, on the main bearings, you might put the bearings in, fully seat them, dry them of oil, then install the main caps dry with the Plastigauge. Then remove the caps and check the width of the squish of the Plastigauge for the bearing clearance. You can do all of the mains this way, then remove the crank and lube all of the bearings and install them for good. On those lubed main bearings, then rotate the crank to bring the rod journals up for installation. Dry both bearings, install the rod caps, remove the rod cap and check for squish, then oil everything and put it back together on that journal. Repeat with the other rod pairs. When done, re-check for ease of turning. It might be a bit geeky, but doing this totally dry might result in just a hair wider clearances, but still well within specs. But whether the block or rod size bearings are oiled or not, still a good way to measure things other than use an inside micrometer and a normal micrometer (and related math, as in prior times). Enjoy! NTX5467 What is considered more accurate plastigage or micrometer? What do professional engine builders use? Link to comment Share on other sites More sharing options...
JZRIV Posted February 27 Share Posted February 27 In the case of bearing clearance, I would only trust plastigage because it shows precise clearance after torqueing the bearing cap to spec. Yes one can base clearance using stock rod/bearing specs and how much the crank journals were cut down, but humans make mistakes as well as bearing manufacturers. Plus, unless measuring instruments are calibrated, do you want to trust their accuracy to such a critical part of engine build? Not me! Plastigage verifies the theoretical clearance. How would one accurately measure the ID of a connecting rod with the bearing cap installed and bearing shells in place? Seal installed or not, it won't have effect on bearing clearance check. 1 Link to comment Share on other sites More sharing options...
NTX5467 Posted February 27 Share Posted February 27 1 hour ago, JZRIV said: How would one accurately measure the ID of a connecting rod with the bearing cap installed and bearing shells in place? There is a specific type of micrometer which measures the internal diameter of the bearings when installed in the caps and torqued to spec. Then that length can be verified with a normal outside diameter micrometer. Some of the old MOTOR manuals and such show them in use. Plastigauge is a relatively new invention, from the middle 1960s or so. Take a calibrated diameter of plastic and place a bit on the crank journal, install the bearing and cap, torque to specs, remove the bearing cap to see how wide the plastic squished out to. Compare it to the scale on the wrapper to see what the clearance is. No math or knowing how to best use the two micrometers. Quick and easy and accurate. For most automotive engines, the "green" PG is what's needed. The "red" is for wider clearances. Enjoy! NTX5467 Link to comment Share on other sites More sharing options...
XframeFX Posted February 27 Share Posted February 27 Link is AMA Spec for 1969 430 cu. in BBB - Page #6 of PDF: https://autohistorypreservationsociety.org/wp-content/uploads/1969-BUICK-AMA-SpecsLeSabre-Wildcat-Electra-225-Riviera-REV-Pg-1-35.pdf 1 Link to comment Share on other sites More sharing options...
Mister Fab Posted February 27 Author Share Posted February 27 Plastigauge done today on all the crankshaft caps and all the connecting rods, everything is ok! 👍😅 The crank has been reworked perfectly. And silicone seals ordered too from BOP 👍 3 1 Link to comment Share on other sites More sharing options...
Mister Fab Posted March 3 Author Share Posted March 3 Much better with the silicone seals. They arrived in 3 days in France ! 👍 4 1 Link to comment Share on other sites More sharing options...
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