2X2KOB Posted February 3, 2006 Share Posted February 3, 2006 Is the phase-2 SOHC 2.5l engine in my 2000 Outback an interference or non-interference engine? Has anyone ever experienced a broken timing belt with one of these cars and lived to tell the tale? Link to comment Share on other sites More sharing options...
edrach Posted February 3, 2006 Share Posted February 3, 2006 Interference. Is the phase-2 SOHC 2.5l engine in my 2000 Outback an interference or non-interference engine? Has anyone ever experienced a broken timing belt with one of these cars and lived to tell the tale? Link to comment Share on other sites More sharing options...
idosubaru Posted February 3, 2006 Share Posted February 3, 2006 friend of mine repaired one that broke a timing belt. said it wasn't that bad, had to replace a valve or two but otherwise no other damage. even the dealer said they've fixed them before with broken belts (Hanover, PA Subaru dealer). i trust my friend more than random conversation with a guy i don't know, but he said he has done it before and hadn't seen too many with block damage. but with any interference motor the possibilities are endless. give more details and we may be able to help more. Link to comment Share on other sites More sharing options...
ferret Posted February 3, 2006 Share Posted February 3, 2006 FYI, This comes up alot: ALL 2.5L ARE Interference, doesn't matter if it's a DOHC or SOHC ALL 4 Cyl DOHC ARE Interference ALL 4 Cyl 97 and newer are interference. This was the year the 2.2 went to Solid Lifers. Which makes it a fact, ALL US Spec Subaru 4 cyl 97 or newer are interference engines. Link to comment Share on other sites More sharing options...
idosubaru Posted February 3, 2006 Share Posted February 3, 2006 FYI, This comes up alot: ALL 2.5L ARE Interference, doesn't matter if it's a DOHC or SOHC ALL 4 Cyl DOHC ARE Interference ALL 4 Cyl 97 and newer are interference. This was the year the 2.2 went to Solid Lifers. Which makes it a fact, ALL US Spec Subaru 4 cyl 97 or newer are interference engines. you're shouting? Link to comment Share on other sites More sharing options...
ferret Posted February 3, 2006 Share Posted February 3, 2006 Reason for the SHOUTING.......recommended maintenance on the timing belt should NOT be ignored. I am not aware of any motors today with a timing belt that are not interference. So take the scheduled maintenance seriously. Your vehicle, your money. Like an old commercial, "pay me now, or pay me later". Link to comment Share on other sites More sharing options...
2X2KOB Posted February 3, 2006 Author Share Posted February 3, 2006 Thanks - I thought it was interference too, then I saw this reference: http://www.toad.net/~rrubel/outbackfaq.html that said otherwise. It's all the way to the end of the file. Link to comment Share on other sites More sharing options...
idosubaru Posted February 3, 2006 Share Posted February 3, 2006 Reason for the SHOUTING.......recommended maintenance on the timing belt should NOT be ignored. agreed. timing belts can break otherwise as well. failed water pumps or pulleys ruin even new belts on occassion. that's why i replace it all. Link to comment Share on other sites More sharing options...
moab austin Posted February 4, 2006 Share Posted February 4, 2006 so what about a 95 2,2 imprezza? I was led to belive its a non interference? Link to comment Share on other sites More sharing options...
ferret Posted February 4, 2006 Share Posted February 4, 2006 95 2.2L in any US Spec Subaru is non-interference. Link to comment Share on other sites More sharing options...
edrach Posted February 4, 2006 Share Posted February 4, 2006 It is non-interference; EJ22 engines were non-interference up to and including 1996 model years. Note I said model year and not manufacture date. so what about a 95 2,2 imprezza? I was led to belive its a non interference? Link to comment Share on other sites More sharing options...
jjou812 Posted March 14, 2006 Share Posted March 14, 2006 93 impreza 1.8L interference? Link to comment Share on other sites More sharing options...
idosubaru Posted March 14, 2006 Share Posted March 14, 2006 93 impreza 1.8L interference? non interference. Link to comment Share on other sites More sharing options...
johnceggleston Posted March 14, 2006 Share Posted March 14, 2006 on a side note..... i heard that the valves don't collide with the pistons in a subaru interference engine (atleast the dohc). but that the valves collide with the valves and some bend. therefore they can be repaired. any truth to this rumor. i guess we should schedule our timing belt failure to coinside with our head gasket failures. john non interference. Link to comment Share on other sites More sharing options...
idosubaru Posted March 14, 2006 Share Posted March 14, 2006 the valve only go up and down so if they collide they collide, if they don't they don't. can't imagine the t-belt changing that, but i could be wrong. the ports can't overlap, so someone explain if that's true. i've worked on 2.5's and 2.2's, but never DOHC. in the interference motors you'll have piston to valve contact. level of damage will vary. Link to comment Share on other sites More sharing options...
ferret Posted March 14, 2006 Share Posted March 14, 2006 John, the 2.5L DOHC is all interference....valve to valve..and piston to valve. Belt Maintenance on any interference engine can be catastrophic if the belt snaps at high rpm's. Doesn't matter what the valve hits, another valve or piston, the cylinder looks like a grenade went off inside, and the motor is trash. I have read a few who broke at low RPM, and got away with only a belt replacement, but the 2 I saw, and Emily from CCR can attest to, they do severe damage at speed. Link to comment Share on other sites More sharing options...
idosubaru Posted March 14, 2006 Share Posted March 14, 2006 valves will hit valves....after the piston smashes them sideways! Link to comment Share on other sites More sharing options...
johnceggleston Posted March 14, 2006 Share Posted March 14, 2006 my understanding was that the valve stems were angled away from each other, riding on 2 different cam shafts. as a result, the valve bodyies were overlaping if both were extended. i feel like ive seen a picture of a piston with cutouts (half moon shaped) for piston valve clearence. but i don't open engines and work on them. i does not surprise me that a failed timing belt would detsroy an engine. the valve only go up and down so if they collide they collide, if they don't they don't. can't imagine the t-belt changing that, but i could be wrong. the ports can't overlap, so someone explain if that's true. i've worked on 2.5's and 2.2's, but never DOHC. in the interference motors you'll have piston to valve contact. level of damage will vary. Link to comment Share on other sites More sharing options...
eventoday Posted March 14, 2006 Share Posted March 14, 2006 i barely lived to tell the tale. one of my pulleys blew into pieces. 13 of 16 valves were destroyed. it has been one long nightmere so iwould recomend changing tensioners and pulleys Link to comment Share on other sites More sharing options...
idosubaru Posted March 14, 2006 Share Posted March 14, 2006 my understanding was that the valve stems were angled away from each other, that's definitely interesting. in any event, a friend of mine that owns his own business fixed one last year that threw a belt. said it wasn't that bad at all. needed one or two valves and the pistons and cylinder walls were fine. probably a slow speed break i guess. Link to comment Share on other sites More sharing options...
nipper Posted March 15, 2006 Share Posted March 15, 2006 Is the phase-2 SOHC 2.5l engine in my 2000 Outback an interference or non-interference engine? Has anyone ever experienced a broken timing belt with one of these cars and lived to tell the tale? 95% of the time, its just a bent valve or two that have to be replaced, but that still adds a huge repair bill. Its important that if you get a flashing CEL that the car be checked out . One of the causes for a flashing CEL is the cam and crank postions sensors being slightly out of synch ... caused by a timing belt with some play in it. Timing belts need to be changed before thier service interval. Rarely in the last 15 years do youhear of one breaking with no other cause that was properly maintained. nipper Link to comment Share on other sites More sharing options...
AWDCar Posted May 1, 2006 Share Posted May 1, 2006 So is it fair to say that if a timing belt goes on a pre-97 motor (non-interference) it will NOT do any damage to the motor? Link to comment Share on other sites More sharing options...
idosubaru Posted May 1, 2006 Share Posted May 1, 2006 So is it fair to say that if a timing belt goes on a pre-97 motor (non-interference) it will NOT do any damage to the motor? your question is loaded. Yes. And no. you already answered the question yourself by including the disclaimer "non-interference". If a timing belt breaks on a non-inteference engine then there will not be any internal engine damage regardless of year, make or model. but you said "pre-1997", not all pre-1997 subaru's were non interference. i think the 1996 2.5 liter motors were interference as well as the subaru SVX EG33. the 2.2 liter pre 1997 engines are all non-interference engines. a generic statement might be, "all non-SVX (EG33) 1995 and earlier subaru's are non-interference". Link to comment Share on other sites More sharing options...
Wayne Boncyk Posted May 1, 2006 Share Posted May 1, 2006 You are indeed correct. The 1996 2.5L DOHC engines are "interference," in the sense that both intake and exhause valves cannot be open simultaneously. They hit each other in that mode, with nasty consequences. Still, if my memory hasn't completely failed me, there is enough clearance in that DOHC design so the valves don't actually contact a TDC piston when they're open. Bottom line - there are different flavors of "interference." Link to comment Share on other sites More sharing options...
DerFahrer Posted May 2, 2006 Share Posted May 2, 2006 Okay, here's the scoop. Any EA-series engine is non-interference. ANY and ALL DOHC Subarus are valve-valve interference. Yes this is properly called 'interference' because as has been explained in previous posts, serious damage can result that requires the engine to be torn down. NOW, the SVX EG33 is technically valve-valve interference since it is a DOHC engine, but the EG33 was the only Subaru engine to have one cam gear-driven off the other. So unless your cams got out of sync with each other, which is a HIGHLY-unlikely scenario, it is basically a non-interference engine. As best I know (so I could be wrong), but all 97-up NONTURBO Subaru engines (besides the SVX EG33) are piston-valve interference. This includes the EJ22EZ (Phase II), EJ25 (all versions including EJ25D, EJ251, and EJ253), and the EZ30D. The EJ205, EJ255, and EJ257 are all turbo motors, therefore they have different-shaped pistons in the interest of lower CR's that might not interfere with the valves. But I cannot CONFIRM this. 1 Link to comment Share on other sites More sharing options...
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