The Dude Posted January 20, 2006 Share Posted January 20, 2006 Sure. The rings may have become prematurely worn as a result of the engine oil losing visocosity through overheating. Or the rings may have lost their temper("spring") through overheating. Replacing the rings will only cure excessive oil consumption IF worn or slack rings are the problem. There are a number of other areas where leakage could be causing oil consumption. If your cylinder liners are worn, for example, replacing the rings will not help you. Replacing the entire engine would be the preferred way to go. A "short block" would include a new block, liners, pistons, and piston rings. This a probably a "good faith" effort by Subaru to solve your oil consumption problem. Subaru has already indicated that they will not go the more expensive route of a short block replacement. I hope the new pistons rings fix your problem. Quote Link to comment Share on other sites More sharing options...
Lawsonmh15 Posted January 21, 2006 Share Posted January 21, 2006 Subaru America has said it will allow for the piston rings to be replaced on warrenty. I don't know if this is enough. Someone please correct me if I'm wrong, but if you had bad rings, wouldn't you be blowing a good amount of smoke? I still haven't seen anything about replacing the vehicle. I hate to say it, but I wouldn't want the vehicle back after the engine has been pulled and torn down by techs who have been given instructions of, "make it stop using so much oil". From personal experience, I HATE re-doing other peoples' work. Although I realize I'm being paid to do it; I don't have the same enthusiasm as I do when I'm doing it for the first time. Although these guys are certified techs, I wouldn't be surprised if SOMETHING, didn't make it back the way it was. Quote Link to comment Share on other sites More sharing options...
nipper Posted January 21, 2006 Share Posted January 21, 2006 Subaru America has said it will allow for the piston rings to be replaced on warrenty. I don't know if this is enough. The service rep. couldn't offer any reason why replacing the piston rings would make any difference other than it seems to be standard procedure. Furthermore, Subaru could not provide a guarantee that replacing the rings would make any difference. Does anyone have any suggestions as to why replacing the piston rings would be the procedure for reducing excessive oil consumption? That is actually the resonable repair. The problem is the piston rings. There are two compression rings, and an oil ring that is made up f three parts (last i checked). It sounds like the rings failed, and since it started doing it recently, i doubt its from improper engine breakin. Whay they will do is (most likely) tear it down to the block, replace the rings, and re hone the cylinder walls. The ring size will be matched to the cylinder bore size.There arent alot of reasons that an engine this new burns oil. Since we havent gotten a clairification on what "unusually hot' was, this sounds reasonable. Now if you want to go for a new short block (which is everything minus the cylinder heads and the accessories). Now if you want to talk about the dealer and make a deal on a short block, you can try. nipper Quote Link to comment Share on other sites More sharing options...
bulwnkl Posted January 21, 2006 Share Posted January 21, 2006 I think replacing the rings will fix it. I would suppose, from your posts here, that the rings were either damaged by high temperatures from your mountain trip, or else oil was coked in them by that trip. Either will cause increased consumption. Also, nothing will cause you to see smoke in the exhaust with a consumption rate anywhere near 1 qt/1,000 miles. If it was my car, I'd be pleased that Subaru is offering to re-ring the engine under warranty when the oil consumption is below both their own and SAE's maximum acceptable consumption limit. As nipper said, this is the reasonable repair. I encourage you to accept their offer, be happy (because it will fix the problem entirely IMO), and watch your coolant gauge! Quote Link to comment Share on other sites More sharing options...
blitz Posted January 21, 2006 Share Posted January 21, 2006 Someone please correct me if I'm wrong, but if you had bad rings, wouldn't you be blowing a good amount of smoke?This is a good point. Oil consumption through the rings is a smokey affair, especially during high-vaccum coastdown followed by immediate application of the throttle. Consumption through PCV or guide seals is mostly not visible. This level of consumption'll shorten your cat-con life. **** ******! Quote Link to comment Share on other sites More sharing options...
nipper Posted January 21, 2006 Share Posted January 21, 2006 This is a good point. Oil consumption through the rings is a smokey affair, especially during high-vaccum coastdown followed by immediate application of the throttle. Consumption through PCV or guide seals is mostly not visible. This level of consumption'll shorten your cat-con life. **** ******! Not necassarilly, but it would be hard to tell as the car would have to be moving, and with all the other air flowing around the car, it would dispate in the air quickly. i think (i may be wrong) but blue smoke on acceleration is valves, on deceleration is rings. nipper Quote Link to comment Share on other sites More sharing options...
GTNP Posted January 26, 2006 Author Share Posted January 26, 2006 That is actually the resonable repair. The problem is the piston rings. There are two compression rings, and an oil ring that is made up f three parts (last i checked). It sounds like the rings failed, and since it started doing it recently, i doubt its from improper engine breakin. Whay they will do is (most likely) tear it down to the block, replace the rings, and re hone the cylinder walls. The ring size will be matched to the cylinder bore size.There arent alot of reasons that an engine this new burns oil. Since we havent gotten a clairification on what "unusually hot' was, this sounds reasonable. Now if you want to go for a new short block (which is everything minus the cylinder heads and the accessories). Now if you want to talk about the dealer and make a deal on a short block, you can try. nipper I'm learning a lot from this discussion and feel better able to discuss the problem with Subaru service reps. Thank you to all for your input. Just for your information, when I asked SAE to provide page references that showed the oil consumption standards claimed by Subaru they said: 'SAE has no standards for oil consumption. Every model of vehicle, as well as individual vehicle, will experience it’s own unique rate of oil consumption.' I have to wonder about the misinformation that is being handed out. All I want is to feel secure that I won't have to put 3.5 quarts in between oil changes, and that I won't have to carry a case of oil around. Replacing the rinds sounds like a good offer though there was no guarantee it would be succesful. With a short block, is the short block completely new, or is it an older rebuilt engine? Quote Link to comment Share on other sites More sharing options...
nipper Posted January 26, 2006 Share Posted January 26, 2006 I'm learning a lot from this discussion and feel better able to discuss the problem with Subaru service reps. Thank you to all for your input. Just for your information, when I asked SAE to provide page references that showed the oil consumption standards claimed by Subaru they said: 'SAE has no standards for oil consumption. Every model of vehicle, as well as individual vehicle, will experience it’s own unique rate of oil consumption.' I have to wonder about the misinformation that is being handed out. All I want is to feel secure that I won't have to put 3.5 quarts in between oil changes, and that I won't have to carry a case of oil around. Replacing the rinds sounds like a good offer though there was no guarantee it would be succesful. With a short block, is the short block completely new, or is it an older rebuilt engine? Being a long time member of SAE, i have to agree with them. Every manufacturer has thier own guidelines, as there are some engines out there (rotory) that purpously burn oil. GM has a redicoulously lhigh level of consumption that is acceptable. At one point anything more then one quart per tank of gas was considered excessive. A Short block the case and cylinders, crankshaft, connecting rods are reused, as they dont wear. Keep in mind they are thouroughly inspected and tested. Surfaces are re-procesed. With Subarus, i dont know if pistons are re used or replaced. The standard is to reuse the pistons after inspection. Subaru may replace the pistons with newer ones designed to reduce piston slap. Depending upon how old the car is, if there are enough cores around, it can be either a subaru factory rebuild, or a new short block. Either one is ideal. You have the right to ask what your getting. One person on this list got burned because the dealer rebuilt the engine, and he did not realize it. Make sure someplace on the paperwork it says that it is a subaru supllied engine if you or anyone else goes that route. Replacing the piston rings should correct the problem. They SHOULD be inspecting the cylinder walls, and hone them if its needed. They should be measureing they cylinders and the pistons to make sure they are within spec. The rings should be inserted in the cylinders and the gap of the rings measured to make sure its a proper fit. I may have skiped something since its been years since i rebuilt an engine, but that is what is involved in a ring job. nipper Quote Link to comment Share on other sites More sharing options...
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