Re-ringing Stude engine Aug 2002 ------------------------------ //////////////////I first read this in Hot Rod Mag around 1960: During WWII, our tank engines operating in Africa were experiencing short engine life and extremely rapid cylinder wall wear. The chrome finished ring was developed to cure this problem, and did increase engine by life 4 to 5 times. Dwain G./////////// -------- By honing, I mean deglazing. Just re-ringing an engine with standard bores. There actually does not seem to be all that much taper in the bores. If I had to bore oversize, I'd have the engine out and off to a machine shop. You know, people used to do this kind of job all the time. Now, everybody believes you have to "rebuild" an engine every time it starts to smoke a bit. When Studebakers were current models it was standard operating procedure to drop the pan and heads to rings in-frame. BTW, it IS pretty easy on a 1.5 ton. I had to jack up the front bumper a couple of inches to create sufficient gap between the axle and frame to get the pan out. Even if the taper on the bores exceeds spec, it will run better with NEW rings in the bores than with old worn-out ones. There should be 50,000 good miles left in this engine, which is a lot for truck this size which sees limited use. Gord Richmond ------------------------- Since I am in the engine building business, I finally get to add my .02 worth. Synthetics as well as most of todays 5W30/10W30 weight oils are modified with friction reducers to improve fuel economy. In the past engine cylinder bores were honed to a smooth finish when ductile moly top rings were used. Chrome rings required a rougher finish so a coarse finish stone was used. Then about 15 years ago most manufactures went to high nickel content cast iron for the block materials. The higher water and oil temperatures created by emissions regulations necessitated this change. The result was that the harder cylinder walls needed a much rougher finish for ring seating to take place. The early 80's big block Chevys were the first victims of the change and high oil consumption was a frequent warranty issue. The remedy was to remove the pistons, ball brush the cylinders with a 120 grit hone and reinstall the pistons and old rings! Oil consumption dropped to acceptable levels no matter what oil was used. Today all Japanese, German, or high performance blocks(Goodwrench, Ford SVO, Bodix, etc.) are finish honed with a ball brush in our shop. If your engine was assembled with a chrome top ring and the machine shop used a rough hone as per the ring manufacture's recommendation then no problems should occur regardless of the oil used. If a moly ring was used with a smooth honed finish then straight grade 30W oil will improve the ring seating. In any case please moniter the oil levels weekly for the first 1000 miles. The ring seating process is all done in the first 100 miles so oil consumption will show up immediately. Andy Jones Hickernell Engine Services RQB3466 -------------- /////////It's important to run the engine at about 2400 rpm with NO idle > time to break in the cam and lifters. The heat build up at that > rpm tempers those components. The rings will seat in before that time > is up. I always use an ultra fine hone on the cylinder walls to get > a better ring seal. 600 grit is what I use.//////////// 600 is OK with moly rings, chrome rings like a little coarser hone. I lifter pre-lub will not hurt. AFAIK Lycoming/Continental/P&W/Packard all specify a high quality *non-dispersant* straight oil such as regular Aeroshell in the red cans. Randee Aug 2002 -------------- Jan 2005 MOLY Rings > I am putting moly rings in a 63 R-1 and I am wondering what the ring > gap would be. The rule of thumb is .004 ring gap for every inch of bore. .004" x 3.562" = .014" Another .001/.002 for a supercharged or nitrous engine. The info should be in the instructions. Also....."very" important to ring life and ring performance. The cylinders should have been hones to a fairly fine finish. Finer than standard cast rings. Will it work with a rougher finish.....yes, for a much shorter period of time. And make less horse power. The Moly coating is sprayed on very thin. Last I read, it's only about .015"/.020" thick. Remember...friction is your enemy Another thing for break in....a little motor oil on the piston skirts and a spray of WD-40 on the rings. Again, ring performance facts. Note: the rings don't have any idea what engine they are in! Just that they go up and down and hold the pressure in. The manufacturer's recommendation should be either on the box or the packaging for the individual ring sets. Depends on the individual ring material, but it is not all that critical, usually about .003 per inch diameter. -- wf. That is far beyond what I call not critical. By not critical I mean you can go a few thou either way, particularly larger, and not really affect sealing. In fact you will notice that manufacturer's give you a range for the gap, not an exact gap. As long as the ring gap is somewhere within mfg.'s spec, the critical thing is cylinder wall finish, which is different, finer, for moly rings compared to chrome or unplated. -- ============ jan 2005 //////// I have a set of .080 over pistons, but can not readily find any rings. The usual Stude sources do not have them availale in that oversize. Sealed Power does not show them as available. Hastings shows them for the 194 Chebby, but are pricey w/ questionable availability. Anybody got any?//////// Try Paul Weaver. He is friends with Sandy Olson. I would think he would not mind you trying to contact him though his website. http://www.olsonsgaskets.com/index.html --------------- I just picked up my Sealed Power ring catalog and here is what I found which is the route I would go: E239K moly rings are readily available. Ring widths are 5/64, 5/64, 3/16 which I presume is what your ring lands are cut for. These rings are for a 3.625 bore, so if you order .020 oversize this will be for a 3.645 bore. A .080 oversize bore is 3.6425, so you will have to file fit them down by .0025. I normally like to file fit my rings anyhow. I have a std set myself which will work out well for my .060 over motor. -------------- Yes, the 239K set is for an 8 cylinder motor. --------------- One more note - if you use the moly filled rings, be sure to follow Sealed Power recommendations for final cylinder wall finish. Joel --------