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how hard is it to change timing belt tensioner 2002 OBW?


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Hey Guys,

 

Just had my head gaskets done and timing belt replaced two months ago by a friend.  Over the last week my idle was rough and on my way home the engine barely ran. I thought a rod bearing was failing but with this site and youtube i think it might be my timing belt tensioner.  The sound is in front.

 

Should I have my stealership friend do the timing belt tensioner or tackle it myself.  I have experience at other issues but have stayed away from the timing belt jobs.

 

thanks,

 

Michael

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I'd confirm that the timing is off before going into it further. They can slip a tooth and the engine will run but just barely. Pull the timing covers and see if the timing marks align. If they don't, then go ahead and do the timing job. Here's a really good writeup on how to do it for the SOHC motors. It's not a bad job. Takes an hour or two for those of us who have done them. The first time is maybe 3 hours.

 

http://www.rs25.com/forums/f105/t154453-diy-sohc-timing-belt-change-w-pics.html

 

If you're going to do the timing job, I recommend you replace with a whole kit and not just the tensioner. It's not expensive. gates kits run about 150 with water pump and more like 120 without. Good peace if mind down the road and less wrenching.

 

Be aware that your motor is interference and if it slipped timing there's possible valve damage. Not sure how fickle they are as I've never had an interference motor slip timing yet. If you do proceed with a timing job

 

 

No check engine light or anything? if it slipped a tooth you should get a cam/crank sensor code. How good are your plugs and wires? How new is your MAF? also likely possibilities for a sudden drop in engine performance.

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Its not hard to replace the tensioner with all the timing belt diy's available.  But by the time you take off the timing belt cover, you have done 1/3 of the work to change tensioner and idlers on an 02.   

Edited by mikec03
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thanks guys,

 

I plan on doing the whole kit. The full gates kit @ $130 on amazon, only $30 more than jus the tensioner.  I just got a new belt and water pump on it two months ago, so'll I'll keep one belt for next time.

 

No codes but my familiar P0420.

 

I shouldn't done more research and got a new tensioner on two months ago and got the whole kit then.

 

Mike

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triple check everything. Count the teeth from all the timing marks to the next timing mark. Count after new belt is installed BEFORE pulling the tensioner pin, count AFTER pulling the pin, count again after rotating the crank twice by hand. After the crank is turned, any marks on the belt will no longer be in sync, but tooth counts and timing marks will always be the same.

 

On suggestion from the forum, I put a piece of cardboard on the radiator to help protect it from slipped tools.

Edited by 1 Lucky Texan
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3' breaker is plenty, remove rubber plug on flywheel (top pas side of engine) insert large screw driver or pry bar, wedge flywheel and pop crank bolt free. Same method makes sure you get it tight when replacing. Locktite is not necessary if you get the bolt tight to begin with. Three marks to keep aligned , the crank is easy ,one cam is under tension and one is not. When installing the belt start at the crank keeping tight go around tensioner and drivers side cam , keeping tight continue around to other cam , here is where I will allow the cam to  be off time (towards the fender) a small amount as it will roll towards the crank as you finaly get the belt to slip on , its not hard but its also not easy... be calm it will fit. Do not worry about the lines on the belt do not try to line them up. Once you have the belt on and all your timing marks are good then you pull the pin on your tensioner allowing it to move... now put your ballenser(pulley) on and slowly rotate the engine clockwise around two times until all three timing marks are aligned. I should mention that the passenger side cam has no real mark to align with just straight up with a case seam directly above it is all you get on that side. If after turning over the motor ANY of the timing marks are not dead on then you do it all over... (can be frustrating ) Don't get excited just take your time and you will get it right. Afterwards you will never be afraid to open up the front again because you will be an expert. Very important is getting the ballenser bolt good and tight or the pulley will come loose and do terrible things to your crankshaft and radiator.  I should mention that if you have to repeat this instalation then you will have to compress your tensioner and re install the pin , do this in a vise and do it slowly little turns and it will easily compress and you can place the pin thru all three holes and then remove from vise , your ready to try again . DO NOT FORCE THE TENSIONER, 

Edited by montana tom
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^^ good post, re-compressing a tensioner is always done at a glacial pace - over several minutes.

 

uh, just in case it wasn't mentioned, use the timing line at the back of the crank pulley pointing at 12 - towards the boss with the crank position sensor in it., NOT the triangle/arrow on the front. It will be at about the 3 o'clock position.

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Stripped the block!  

 

 

Everything went ok till….putting in last 14 mm bolt on the smooth idler pulley.  Then i torque down AND STRIPPED the block.

 

I've been torqueing for years and know an idea on ft/lbs but maybe using my 30" breaker bar didn't help.

 

should I repair with Helicoils?   Looking around I see there's another product Timeserts.  

 

I looks like I might get a rt. angle drill or should I end up removing the radiator. 

 

thanks

 

Michael

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When working on the timing components a torque wrench is highly recommended, if not mandatory. The bolt hole that you stripped is speced at only 35 ft lbs. Aluminum threads strip very easily. On the other hand, the crankshaft bolt is speced at 133 ft lbs. Under tightening the crankshaft bolt is fairly common. That creates additional problems. Also, if you are working on a Forester you might want to remove the radiator to gain enough working space. Good luck.

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Michael:  Bummer ! bolt size is 10 x 1.25  Can't believe that you haven't removed the radiator, makes everything easier, and there is nothing to it. Unplug the two fans, Should be able to leave them bolted to the rad. remove the overflow tank if you haven't already, if is an automatic then disconnect the rubber lines to the tranny.  Upper / lower radiator  hose then 2 bolts on top should do it . I have only used helicoil  before,  always worked good for me , but there may be newer better stuff out there that I haven't tried yet. In hindsight maybe... 30" 1/2" drive BREAKER BAR  was a little big... lol oh well ...drill it , tap it and carry on.

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I did this job for the first time on my Legacy 2.2 liter a couple weeks ago and while the engines are a little different the timing job is almost exactly the same except for the tensioner and even that is almost the same. It took me more than 4 hours but I also took my time and did cam/crank seals, resealed the oil pump, new water pump, and all new pulleys and whatnot. Removing the radiator is the way to go for sure. Two fan connectors, recovery tank, two hoses and two bolts. Takes five minutes for soo much more space. 

Montana Tom was spot on with his post a little ways up. The hardest part of this entire job is putting the new belt on. After trying to route the belt so many times and still not getting the marks to line up I was ready to pull my hair out. That is by far the hardest part. I ended up having the passenger side cam about a half tooth off towards the outside, cause I figured when I pull the pin on the tensioner it will pull it towards the driver side and line up. I was right. I spent probably an hour or so trying to route that friggen belt. Like Montana Joe said, stay calm, don't freak out, it will work out. It is tough though. Lucky for me I only had to pull the pin on the tensioner once. It pulled the passenger cam in line when I pulled the pin. Everything after that is cake. Also, when refilling the radiator be sure to follow proper filling/bleeding procedures as it can cause you a real headache if you don't (trust me on that one lol). I fell confident if I had to do another timing job on one of these I could do it in half the time. Not that hard really.

Hopefully everything works out for you and you are able to get that re-tapped. Good luck!

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Michael;  Yes straight is important !!! lol  This happens to aluminum motors. Take your time , use locktite red on your helicoil.  Nicholi mentioned proper filling of the system. Here's how ,  After rad is installed and all the connections except the upper hose are attached and tight. Connect upper hose to engine (with clamp on ) pour your anti freeze directly into the upper hose keep going untill water is staying in the upper hose, quickly swing it over and attach to radiator. Now fill the radiator, there is an air bleeder valve on the pas side top of radiator. I don't use it ... as you get water to show up at the rad cap gently squeeze the upper hose burping the air out . Once its full put the cap on and start motor and turn on the heater inside. Once you get heat in the cab and do your test drive to check things out . Park the car let it cool off then double check your radiator level and overflow level. Your Done... A new subi mechanic is born!

Edited by montana tom
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  • 2 weeks later...

  The timesert worked.  It did have some play in it so I used some jb weld to seat the insert.  Then I put the bolt/pulley on hand tight to center if needed before the jb weld set.  

 

 

Got a snap on torque wrench and got timing belt on.

 

 

  The motor runs better so I think the tensioner might have been needed.  But I still have a pretty loud ticking sound.  A couple of months back my HG went and I limped home watching my temp gauge.  Ever since then there's a cold start strong ticking sound especially 2k-3k rpms.  I've got a video of the motor now.  Should I use a youtube link?

 

do you guys recommend I put radiator back on and just live with the sound?

 

thanks

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