Timing Belt Conundrum

[Smo]

So my 2000 Legacy just died on me on the road.  It made some squeaking noises (sounded like a drive belt having issues) which lasted a few minutes, then stopped.  It ran normally and then died suddenly 40 miles later.  For some reason, I tried to start it again before looking for the problem.  Stupid move.  It sort of started but died immediately.

 

I opened the hood and I could see the timing belt!  I wish I'd taken a picture, it was quite something.  The plastic cover on the front of the engine was worn through or cracked and at least 18" of timing belt is visible (not the whole width of the belt, but some of it).  Scary.  I got it towed to a mechanic for diagnosis - I've done quite a bit of work on the car but nothing as complicated as the timing belt.

 

So I just got a call and the mechanic said he turned over the engine manually and didn't hear any noises, said it sounded normal.  He said that's an indication that I might've gotten lucky, but that the engine could still have been damaged.  He didn't want to speculate on the probability either way.  The car has 208,000 miles on it and the belt was last replaced at 120,000.

 

My options are:

 

1) Pay $600 to have them install a new timing belt, pulleys, etc.  Possibly wasted money if the engine is toast.

2) Get the car towed to my house and do that myself.  Same problem as above.

3) Abandon ship before I sink any more money into it

 

What do you all think?  I didn't hear anything unusual as the car died (either time), and the mechanic didn't hear anything turning the engine over.  Do those two things actually make a difference?

 

The frustrating thing is that I was planning on replacing the timing belt, water pump, pulleys, etc sometime in the next 5-10K miles . . .

[mikaleda]

Personally I would take it home, put a new belt on it and do a compression test. That is cheap and a good way to find out if the valves got damaged or not. If you have good compression then go ahead and do the idlers, water pump and new cover on it.

Its worth a shot for sure

Edited December 6, 2014 by mikaleda

[Smo]

Hmm, I hadn't thought of the compression test.  If I wanted a really cheap test I could go grab a timing belt and the pulley off of a subaru at the local salvage yard.  I know just the subaru (I took an oil pan off it last week).

 

The silver lining here is that I walk to work next year, so I really have no need for a car until the summer.  Plenty of time to figure it out, take the heads out if I need to, etc.  The other silver lining is that I was planning on driving to a remote trailhead next week and this could've happened 30 miles down a dirt road.  o_O  So good timing, timing belt!

[Fairtax4me]

Must be nice to live close enough to work to be able to walk there!

 

A timing job on these is pretty simple. If you have the time and don't need the car back ASAP get it towed home and pull the covers off and see how far it jumped. Its easy enough to hang a new belt on it and start it to see if it runs. I would do that first before pulling the heads off.

[lmdew]

New belt and what ever failed to have the belt chew through the cover.  Most likely one or more of the pulleys are bad.  The toothed idler is the one that fails most often.  If you can find a good set at a yard, that's good enough for a test, but if it's good, you'll do the job again.

[Rooster2]

ebay is a good source for buying a kit that will include a TB, idlers, and pulleys. Reasonably priced too. I have a complete kit installed on my 99 OBW

[Smo]

Thanks for all the great information, guys!  I'm gonna try to fix it myself.  Should be fun, in any case.  I got an offer for a free tow to my house (on a flatbed!) from a friend, so I'll get it here and then deal with it in January after all my winter break hiking trips.  I'll update the thread as I find things out, for future reference.

 

The ebay kits I've found include GMB idlers, pulleys, etc - which seems to be a good brand from my quick research.  But most of them don't state a brand for the timing belt itself.  Any recommendations on a belt brand to search for?

 

And yeah, walking to work will be nice - I'm looking forward to it.  5 minutes each way.

[xdeadeye1]

rockauto has a Gates kit , it includes idlers and belt,  good price, I just did mine. you may need a new belt cover also,, so might want to grab that at the salvage car you mentioned.

 

and I know it might seem im Piling on,, but you may want to consider replacing that  Water pump while youre there...  And hey may as well pull of the Oil pump and put new gaskets in it,, and check the screws..     (just suggestions)

[mikaleda]

+1 on gates, they make a good product

[mikec03]

 

The car has 208,000 miles on it and the belt was last replaced at 120,000.

The idlers were probably not replaced at 120K.  The idlers fail before the belt, from what I read on these forums.  The best idea is to just get the replacement belt and/or idler from the junk yard, put them on, and then test it for compression.  This costs you practically nothing.  If there is no compression on one or more cylinders, then you have a big expense, and you have to decide whether to repair it or buy another used subaru for equal or lower price.  As you probably know, you most likely bent a few valves, but you might be lucky.    

[1 Lucky Texan]

I would only use Gates or Mitsuboshi belts. If you replace the waterpump -  I've read you should use a Subaru METAL gasket and a Subaru or Aisin pump.

 

All but one of the GMB rollers I put in my WRX seemed as good as the original rollers. Of course, I dunno how long they will last. Nothing wrong with doing the next belt change at 80K or 90K instead of 105K if you're worried about the parts quality. Of course, you could also get OEM parts, but they are pricey.

[Smo]

 Got back from my backpacking trips and started the process today.  Need to go get a 22mm socket before I can start on the crank pulley.  Ordered a Gates kit, it should be here by the time I'm ready for it.  But I did take a photo of the belt!

 

 

Edited January 8, 2015 by Smo

[lvsarge]

+1 on gates kit. Replaced all of my idlers and haven't had a problem. Sounds like you jumped a tooth. Probably due to some kind of debris from when you ripped a hole in your TB cover. Good luck.

[Fairtax4me]

That toothed idler got you.

Those things like to fall apart and when they do they chuck the belt out through the cover.

[Smo]

And the plot thickens - working on it today, I was able to start getting my crank pulley bolt loose, by using a hammer on a breaker bar to make a poor man's impact wrench.  Saw that online somewhere.  I also used the trick in this video:

 

 

With those two tricks together I'm able to get the bolt to move (I can look down and confirm that the pulley is not rotating), BUT . . . it doesn't seem to be getting looser.   It's turning but I still need the hammer hits to turn it, I can't do it by pulling (the crankshaft pulley will rotate even with the friction from the belt as shown in the trick above).  I'd say I've turned it close to a half rotation now.

 

So . . . is the bolt stripping, or something going wrong?  Or was it just put on with threadlock (a common thing from what I understand).  Anything I need to do to keep from causing damage, or should I just keep hammering it?  I hit it with PB Blaster preemptively two days ago, and again just now.

Edited January 11, 2015 by Smo

[Smo]

On second thought, I'm starting to question whether it was turning or not . . . could've been wishful thinking.  Now I'm trying to find that damn hole that you're supposed to stick a screwdriver into...

 

EDIT: Got it!  I ended up wedging a piece of rebar in there (couldn't find the proper hole for the screwdriver so I used the one this video shows:

 

 

The rebar seemed way sturdier for that job.

Edited January 11, 2015 by Smo

[Smo]

So I got the cover off and removed the idler pulley.  It wasn't easy to do (the bolt was bent and I had to hammer on the pulley (carefully...) to bend it back enough to take it out...).  It came out with a bit of metal on the threads, so it might have stripped some.  It also removed some metal from around the bolt hole when it was bent like that:

 

 

So . . . is that going to be a problem for the new idler?  Seems like it could be a deal-breaker, but I don't know.

 

I'm also not sure how to time the engine now.  From the research I've done the best thing to do would be to remove the spark plugs to eliminate compression, then turn everything by hand but don't force anything.

Edited January 12, 2015 by Smo

[1 Lucky Texan]

at 208,000 miles, if you can't make yourself confident that chasing the the treads with a tap - or use of a helicoil (or similar repair - others here can advise better than I if that could work) then I'd think a used engine would be a good option. Might find one with 1/3 - 1/2 the miles of the present engine.

[xdeadeye1]

My opinion.. its cosmetic,, get a new pulley and bolt and chase the threads with a tap. 

[myhilo]

What your photos seem to show is good clearance in front of the threaded boss.  What I would suggest is to take your old bent bolt to the hardware store and find a metric nut which will screw onto the bolt.  The nut thread size will tell you what thread/pitch you need, so buy a tap of that size, they can help you at the hardware store if you explain to them what I am suggesting.  The tap you buy will be inexpensive <10 bucks,  the size will be something such as M6 x 1.0 which means 6.00 mm bolt diameter by 1 thread per mm of pitch.  Another common size is M8 x 1.25   The tap you buy will be shaped with a tapered point.  This taper will allow you to turn in the tap into the threaded hole for easy starting but it will also bottom out on the blind hole your photos show.  This means that you will be able to start the tap into the old threads but as you turn the tap and the cutting edges clear out threads of the hole the tap will bump it's tapered end into the bottom of the hole before you have cut new threads to the bottom of the hole.  What you will want is to be to cut threads deeper into the bottom of the threaded hole.  The new deeper threads will give you additional strength for your pulley bolt. To get threads deeper into the hole you can take your tap and grind the pointed part down to make what's referred to as a bottoming tap. You will need a bench grinder or even a rotary stone on a 1/4" drill shank.  This will take a long time if you just have a drill and a rotary stone, but it will be cheap.  Be sure to keep the tap cool by dipping it in water as it heats up from the grinding.  The final shape you want to achieve is full threads almost to the bottom of the tap, having shortened the tap by grinding back all the tapered part.  If you go to a auto parts store and ask them to show you a thread chasing tool set you will see the shape of the tip of the tap that you will want to make.  Notice that the thread chasing taps have a blunt threaded end with a slight bevel at the last thread.  This is the shape you want to make you single tap be like after the grinding.  This is now a 'bottoming tap.  It will be harder to start without cross threading so be sure it threads in by hand only.  But it will follow the threads in the tapped boss and will cut down further into the hole giving you new additional threads to strengthen the new bolt.

 

A few things you need to be very careful of is:

 

First; make sure the tap you first buy is started correctly, exactly at a right angle to the boss, not tipped over at all. This is just like the care needed when you thread a bolt into a hole, it just takes even more care because the tap is a cutting tool and will cut new threads with the same twisting effort as a normal bolt would need, so it's real easy to mess up the threads already there by cutting new threads on top of the existing threads and that will just weaken the metal and stop a normal bolt from being threaded in.

 

Second: the tap will come with a square drive on the shank and is intended to use a special 'tap wrench' to firmly grip and turn the tap.  You will have to improvise with a adjustable wrench closed up quite small to fit the flats of the square drive.  Additionally, a tap wrench has a short handle which gives better control and lessens the amount of twisting force you can apply.  This is part of the tool design, because most of the time a tap is cutting new threads into steel and they don't want you to use too much torque, because taps are made of hardened steel which won't bend, instead it will break suddenly.  This would be very BAD. Broken taps inside a threaded hole are almost always fatal to part the tap is broken into.  So the tap wrench's short lever arm makes the mechanic stop and see what's wrong before he breaks the tap.

In your case will be using an adjustable wrench with WAY too long a lever arm so be WARNED,  Make sure the tap is started correctly and use very little force.  You will be cutting into aluminum, use some WD40 or other light oil to lubricate the tap cutting. But the tap will go into the aluminum like butter not needing much force at all. 

 

Third: the first time you use the tap, it will be long and tapered as it is when new and as you turn it in chasing the existing threads,  it will suddenly come to the bottom of the hole and stop turning.  It will not want to turn further at all, so don't forced it.  Remember you have way too much lever arm and it's very to easy force things.  This could punch the bottom of the soft aluminum hole breaking the engine block or you could strip out the threads with the tap again setting you back and creating new, more serious problems.

 

Fourth: the second time you use the tap you will have cleaned up the original threads and will be cutting new threads at the bottom of the hole and again it will be very easy to OVER torque the tap as it comes to the bottom of the hole.  It will jam in place and must be backed out.  So, go slow as you near the bottom of the hole, removing the tap after each full turn and checking your progress.

 

Lastly, you will need to make a custom bolt just slightly longer than the original one which will thread in deeper and take advantage of the new, deeper threads.

 

All these procedures are a little touchy to do, but I've use this technique many times to repair machines with a stripped thread.  Bear in mind that this takes about the same level of skill as using a helicoil installation does and if this technique doesn't work, you can still go the helicoil route, but all the 'blind hole' precautions still need to be taken.

 

pm me if you like, I can give you more details.  Watch a few you tube videos on tapping a hole to get more help, and good luck, what I've suggested requires very little money to get you to the next step in reinstalling the timing belt so you can proceed with your testing.

[Fairtax4me]

Which idler failed? The tensioner idler (large smooth one) bolts to a bracket that bolts into the block. Remove 2 bolts and the bracket pops off. Grab a "new" one from a junkyard.

 

The toothed idler bolts onto the water pump. New pump, new threads, new mounting boss.

[Smo]

myhilo:  Thanks for all the detailed information!  I have tapped a few holes before, but don't own a tap set and that sounds like a nice workaround to have in the toolbox.

 

fairtax: yep, it's the toothed idler, and I do have a replacement water pump, so I guess that solves it.  Thanks!

[Smo]

Well here's an interesting issue - the FSM seems to indicate that the distance between the camshaft mark and the passenger's side cam mark should be 44 teeth, and to the driver's side 40.5 teeth.  But the marks on the Gates belt don't match that - one is 44 teeth and the other is longer - 47 or 48.  Anyone know what's up with that?

 

I double-checked the length of the belts and the Gates is definitely a match for the OEM belt that I removed.  And all the pulleys and such match up.  So I didn't order the wrong kit or anything.

[heartless]

it is not that uncommon for the marks to be wrong - count the teeth and use a white paint pen, or a silver sharpie to make a mark at the correct count.

[Fairtax4me]

Don't go by marks on the belt. Just totally ignore them. If it has arrows to indicate direction of rotation, pay attention to those, but not the alignment marks.

Line up the dashes on the sprockets with the vertical seam in the cylinder head. Make sure the crank sprocket has the notch/dot on the BACK edge of the sprocket lined up with the notch in the oil pump housing.

 

If the drivers side cam sprocket mark doesn't line up perfectly with the seam when the belt is on, make sure the mark is slightly toward the drivers side. That will even out as the belt wears and stretches.