mickytrus Posted July 22, 2017 Share Posted July 22, 2017 Just wondering about possible damage that can incur when interference motors snap a timing belt. Valves bend but, what other damage can occur..... I am thinking about lower end damage...... Specific example:::: would be 98 EJ22 motors. Thanks, Micky Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 22, 2017 Share Posted July 22, 2017 The intake valves get bent. That's it. GD Link to comment Share on other sites More sharing options...
hzimmerman1111 Posted July 22, 2017 Share Posted July 22, 2017 I have some first-hand experience and just finish repairing my friend's '01 OB EJ251. Here is my post started this May. http://www.ultimatesubaru.org/forum/topic/163483-outback-01-does-not-run-after-14k-with-ej25-changeout/ The belt broke going about 55 mph. No way do the intake valves survive it but everything else was fine including the pistons. I got it back on the road with just rebuilding the heads and reassembly with the usual assortment of parts . HZ Charlotte 2 Link to comment Share on other sites More sharing options...
montana tom Posted July 23, 2017 Share Posted July 23, 2017 Sometimes the exhaust valves get bet as well. Like HZ said replace all the valves & reassemble . Haven't seen any piston damage yet. Link to comment Share on other sites More sharing options...
wtdash Posted July 23, 2017 Share Posted July 23, 2017 (edited) NOT an Ej22, but bought an '03-ish 2.5 which had a broken T-belt....I was 'told' it was just valves...but @ least one piston was cracked too....probably pics on here....YEP. Edited July 23, 2017 by wtdash Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 23, 2017 Share Posted July 23, 2017 That's rare enough that I haven't seen it (on a Subaru). The valve broke completely off which is possible but again super rare. I've personally thrown a 251 belt at freeway speed and that didn't happen. GD Link to comment Share on other sites More sharing options...
idosubaru Posted July 23, 2017 Share Posted July 23, 2017 the few i've seen were lots of bent valves and one friend got lucky with no damage, still driving car now many years since i repaired it. Link to comment Share on other sites More sharing options...
mickytrus Posted July 24, 2017 Author Share Posted July 24, 2017 Sounds pretty encouraging..... In this case, that I am presently dealing with...... Seems like the Driver's side head....... Is crapped out.... as for the passenger side head I think it is ok.......... <<<<<This is why I think this>>>>>> I tried to put a timing belt on it...... you know.... set up the marks Arrows point upward on both cam sprockets and the crank.... Passenger side head, cam spins nicely when spinning the cam sprocket.... and when arrow is up... there is no tension(no lobes of cam in contact..... Driver's side head, it spins but, it is tight and there is always tension and ...... impossible to set up the mark on the cam when piston is moved into position... cam spins out of position...(because the valve is bent and is pushed by piston) SO I would like to think that the passenger side head is still ok... that is has not suffered any damage........ is this as dangerous assumption?????? How about a method to test the valves.......... maybe by compressing air in the cylinder and see if there is leak off?: Any suggestions????? Is there the possibility that the passenger side head is still ok//// it certainly feels ok...... If anybody can chime in..... it would be greatly appreciated...... Thanks, Micky 1 Link to comment Share on other sites More sharing options...
Subaru Scott Posted July 24, 2017 Share Posted July 24, 2017 It is normal for the drivers side to feel that way, as it is ramping up on valves where the marks line up. I'm assuming your belt did break? You should assume you do have bent valves if so. You can install the belt and do a compression test to find out for sure. Unplug the fuel pump or injectors while testing. You do NOT want to try and run the engine unless your compression check shows good . Like at LEAST 160 psi in every cylinder. Trying to run the engine risks breaking a valve that is bent, resulting in piston/cylinder damage. Link to comment Share on other sites More sharing options...
Northfield Posted July 24, 2017 Share Posted July 24, 2017 I had the toothed rubber belt pop over a notch (not even break) on an older (1969) Fiat 124 Spyder, twin overhead cam 4-cyl., once at highway speed, that engine is high-compression (I think over 10:1) and it buried a valve deep into the piston. When it went "Boom!" my chum had the good sense to instantly push in the clutch. Basically, was welded in there from the force of impact. After the descriptive from by buddy who I had loaned it to, and who towed it back to my place, I pulled the head off (easy enough to do on those cars), took a look at the damage, and dropped in a spare engine from a wrecked Spyder. A lot easier than attempting to rebuild. They were small engines (I think about one liter). You can do an incredible amount of damage with a busted belt (or chain) on an interference engine. Ouch. I sure would not attempt to turn it over if you plan to rebuild, you risk doing a lot more damage. Link to comment Share on other sites More sharing options...
Subaru Scott Posted July 24, 2017 Share Posted July 24, 2017 You would have found, after deeper investigation, that the opposite happened. The valve dropped, because it was over-revved, or the keepers let go, or it seized. THEN the belt skipped a tooth because of the loose spring/retainer or stuck stem jamming the cam. One tooth off will certainly not bury a valve in a piston. 1 Link to comment Share on other sites More sharing options...
idosubaru Posted July 24, 2017 Share Posted July 24, 2017 (edited) Passenger side head, cam spins nicely when spinning the cam sprocket.... and when arrow is up... there is no tension(no lobes of cam in contact..... Driver's side head, it spins but, it is tight and there is always tension and ...... impossible to set up the mark on the cam when piston is moved into position... cam spins out of position...(because the valve is bent and is pushed by piston) You're assumptions are wrong and your engine is fine. Make sure you're using the correct crank mark, some people use the wrong mark on the crank sprocket, dot instead of the pulley I guess? either way - you seem new to this so you could easily be using the wrong mark. It is normal for the drivers side cam to be under tension and want to spring out of the 12 noon position because it's compressing the valves at that time. Totally normal. Just carefully move it into position and it will stay there. Edited July 24, 2017 by idosubaru 1 Link to comment Share on other sites More sharing options...
mickytrus Posted July 24, 2017 Author Share Posted July 24, 2017 First, thanks for this input in to this situation, definitely invaluable.... The belt did snapped while the vehicle was driving. The car was under some load going up hills(mountainous traverse) I was probably driving 40mph or so.... Yeah, I know that sound of belts breaking from non-interference 1.8l's letting go..... (not really a big deal-have changed them on the side of the road) So, fortunately I was in a place to pull off on this hill. I had plenty of tools with me and a jack. I removed everything down to the belt(including lower pulley. (Yes, belt snapped) From reading several responses to my post.... SubaruScott: You should assume you do have bent valves if so. You can install thebelt and do a compression test to find out for sure. Unplug the fuelpump or injectors while testing. You do NOT want to try and run theengine unless your compression check shows good . Like at LEAST 160 psiin every cylinder. Trying to run the engine risks breaking a valve thatis bent, resulting in piston/cylinder damage. This makes alot of sense (if I can install the belt,cause it didn't feel right) IdoSubaru: It is normal for the drivers side cam to be under tension and want tospring out of the 12 noon position because it's compressing the valvesat that time. Totally normal. Just carefully move it into position andit will stay there. What Idosubaru mentions above, is somewhat what I had felt(physically) while I attempted to install the belt. I did eventually get the driver's cam to sit in this position. What caused my hesitation to continue with this roadside repair, was that when I moved the crank arrow to its position after having both passenger side and driver's side cams it their respected positions(arrows to notch in back of cover), the driver's side cam would pop out of position. I kinda got the feeling that the process of moving the crankshaft to it's desired location was bumping into a bent valve(driver's side head) and forcing the driver's side cam to spin clockwise. Thanks, Micky Link to comment Share on other sites More sharing options...
Gloyale Posted July 24, 2017 Share Posted July 24, 2017 I've seen teh valve guide crack in addition to bending the valves. Insepct them carefully before just slapping a new valve in. Link to comment Share on other sites More sharing options...
idosubaru Posted July 25, 2017 Share Posted July 25, 2017 Hmmm. I've never seen the piston push a valve like I think you are thinking. But I've always diagnosed bent valves without doing much extra diagnosis to know if that would happen. +1 to guides, I'm always worried whether their damaged or if a valve can bend a little bit that I can't tell. Use excellent gaskets and resurface the heads no matter what. Link to comment Share on other sites More sharing options...
Gloyale Posted July 25, 2017 Share Posted July 25, 2017 when I moved the crank arrow to its position after having both passenger side and driver's side cams it their respected positions(arrows to notch in back of cover), the driver's side cam would pop out of position. You should be aligning to the hashmarks at the outer edge of the pulleys. NOT the arrows, those are for Valve adjustment. Could be part of the problem. But if you broke the belt at speed, I would figure on needing to pull both heads and replace valves. Link to comment Share on other sites More sharing options...
uniberp Posted July 25, 2017 Share Posted July 25, 2017 (edited) ... when I moved the crank arrow to its position after having both passenger side and driver's side cams it their respected positions(arrows to notch in back of cover), the driver's side cam would pop out of position. I kinda got the feeling that the process of moving the crankshaft to it's desired location was bumping into a bent valve(driver's side head) and forcing the driver's side cam to spin clockwise. The trick is to use a breakerbar/socket, not a rachet to pull the belt onto the pulley. If the belt slips the breaker bar will prevent the pulley form advancing from spring force. You can back it up and try again. Once the belt is almost on the pressure will hold the pulley in place so you can re-position the breaker and socket for a better grab to pull it the rest of the way on. Edited July 25, 2017 by uniberp Link to comment Share on other sites More sharing options...
Gloyale Posted July 25, 2017 Share Posted July 25, 2017 The trick is to use a breakerbar/socket, not a rachet to pull the belt onto the pulley. If the belt slips the breaker bar will prevent the pulley form advancing from spring force. You can back it up and try again. Once the belt is almost on the pressure will hold the pulley in place so you can re-position the breaker and socket for a better grab to pull it the rest of the way on. IDK what you mean "pulling" the belt on. Should be no need for that. Belt should not be stretched AT ALL for installation. Simply slip it into place with the lower smooth roller and the tensioner not yet installed. Line up the belt to all 3 marks, and then install the compressed and pinned tensioner. This will be engouh to keep it from slipping yet. Then install the lower smooth roller, making sure to lift up on the belt to get enough room to install the bolt straight and not crossthreaded. Last step pull pin. No need to stretch or pull the belt with wrenches or whatever you are describing. Link to comment Share on other sites More sharing options...
mickytrus Posted July 26, 2017 Author Share Posted July 26, 2017 Gloyale thanks!... This sounds like part of my problem...... I will try and install and do compression test...... Any recommendations regarding a type of compression tester... those plug holes are rather far far away????? Thanks! Micky Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 26, 2017 Share Posted July 26, 2017 You don't need to compression test it. Just pull off the valve covers and check the valve lash after correctly timing it. If the lash is really huge on any of the intake valves then they are bent. GD 1 Link to comment Share on other sites More sharing options...
AdventureSubaru Posted July 27, 2017 Share Posted July 27, 2017 (edited) Gloyale thanks!... This sounds like part of my problem...... I will try and install and do compression test...... Any recommendations regarding a type of compression tester... those plug holes are rather far far away????? Thanks! Micky Once you get the belt on properly, you will probably know for sure one way or another as it will either sound normal, or barely run. If it sounds normal, do as GD suggested and check lash. I bought my 98 legacy with a jumped timing belt. I replaced a failing idler and the belt with used parts by way of checking and it eventually started and moved but was really plunky. I ended up getting a cheap used 96 EJ22 and dropping it in. Others just get a set of used heads and the felpro head gaskets (Same as Subaru but for $25 each) and put it all together. If you do the work yourself it wont run you more than a few hundred dollars. But step one is to get a good timing belt on there. Fox's videos are great to get the right visuals. #1 mistake is to mix hash marks and arrows. Use the hash marks only. I turn it over by hand two full revolutions and make sure it all lines up before starting it. ignore the marks on the belt. If the hash marks line up, it's timed. Edited July 27, 2017 by AdventureSubaru 1 Link to comment Share on other sites More sharing options...
mickytrus Posted July 28, 2017 Author Share Posted July 28, 2017 much appreciated thanks! checking lash with a feeler gauge?????? How much lash on the valves? in thousands...... or if you only know MM.... Is it the same amount of lash for intake valves as well as exhaust valves? Yes, I believe I mixed the arrows with the hash marks. I could barely see anything but the arrows, It was night on the side of a desolate road. Do you have any recommendations as to what I should do to better see these hash marks?????? how to shine up the side of the pully etc. etc. etc. Thanks, Micky Link to comment Share on other sites More sharing options...
mickytrus Posted July 28, 2017 Author Share Posted July 28, 2017 Thanks for the link to Miles Fox and the Subaru Alliance.... So he runs without timing belt covers..... What is the consensus on that? Do any of you run without timing cover? And what are you thoughts about not running with timing covers.... I myself threw away my timing covers on my EA82's a very long time ago.... and I really like the idea of not running covers. but, that was with the EA82's I would really like know what everybody else is doing.... with the EJ motors and the timing covers... Thanks, Micky Link to comment Share on other sites More sharing options...
golucky66 Posted July 28, 2017 Share Posted July 28, 2017 If it's an interference motor, run without covers at your own risk. Knowing that anything getting up there can cause the belt to slip, jump, break, etc and you need valves then. I've heard some people run without them. I would not on an interference engine. Link to comment Share on other sites More sharing options...
matt167 Posted July 28, 2017 Share Posted July 28, 2017 (edited) So, I'm working on a '04 WRX that was in a 'not shop' for a head gasket job and timing belt just to get the car back on the road... And the guy working on it was a clueless monkey who claimed to have a clue but, had less than an incling of a clue... He gave up on it partially dissasembled but engine still in car What we learn today is that you don't pull the timing covers and timing belt before pulling the engine, especially if you plan to roll the engine over... Now essentially the best way out is a new or used long block. Since it was so tired anyway ( EJ207 was the eventual swap ) So yeah, Subaru's are also susceptible of incapable mechanics Edited July 28, 2017 by matt167 Link to comment Share on other sites More sharing options...
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