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'98 legacy 2.5 DOHC Timing Belt Alignment Question


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First time doing a timing belt and water pump replacement on a 1998 Legacy GT 2.5 DOHC engine. I have the timing belt kit coming in and am now breaking down the car. I have factory service manual in hand and have reviewed all videos, instruction I can find.

I just want to confirm one observation: I've aligned all marks from crank and cams properly before removing old belt and when I release the tension from the belt and remove it, the left side intake and exhaust cam sprockets will jump off line as I imagine they are partially open and under spring load? correct?

When I install new belt and align I will need to turn the left side cam sprockets in the correct direction one at at time in order to re-align.

Question: When lining the left side back up, is it correct for both the intake and exhaust cams to be under spring stress when aligned as they were before removing belt? When turning each one more tooth would have it spring off alignment? 

I just want to be sure that this is the correct experience.

Thanks for your help guys!

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Drivers side is under load.

 

That's why they turn easily.  Makes hanging the new belt a bt of a challange as well.  I use clamps or clothes pins.

 

You doin gcrank & can seals?  Checking those oil pump screws?

 

Welcome ot the USMB!

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The screws that hold the backing plate on the oil pump can get loose and back out. Only takes 20 minutes to take the oil pump off, blue loctite the screws, and reseal it and put a new pressure o-ring on it. Migt as well do it while you're in there.

The o rings are like $3 at the dealer and they keep them in stock.

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Thanks for the feedback guys.  Looks like I have a new problem with the timing belt alignment.  

 

Everything was aligned when taking the old belt off and eventually also when putting the new belt on.  SInce we also had to do the water pump, we were torquing the left/driver cam pulleys with the belt on and a pulley skipped a tooth or two.  We decided to remove an idler pulley and tensioner and start over.  The problem is we went and took the belt off mistakenly at a random engine position, so now the alignment is unknown.  I'm not sure what specific sequence to follow to get everything positioned correctly.  We need to turn the crankshaft and all four intake/exhaust cams.  The manual talks about the proper rotation for driver/left cams but not for the passenger/right cams, and the right exhaust is now partially compressed.

 

What is the proper sequence to rotate everything to get back to the proper installation marks?

 

Thanks alot!

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Doh!!!

 

I use the old timing belt wrapped around the sprocket I need to tighten and either the crank sprocket or one of the bolts that hold the idlers on. The jyou can crank down on the sprocket bolt without jumping the belt.

 

Anyway, to get back in time look at the timing notch on the crank sprocket. How far is it away from straight up? If its within 45 degrees of straight up you can safely turn it to the proper mark on the oil pump housing and proceed to resetting the cams. Look at the marks on the cam sprockets and turn them in the direction that points to their proper timing mark 90 degrees at a time. If the mark on the sprocket is between 1- 5 o'clock, turn the cam counter clock-wise. If between 6 -12 oclock, turn clockwise. Only turn 90 degrees then move to the next cam, upper or lower on the same side. Do only one side at a time. Use a wrench and turn slowly. If you feel the camshaft bind at any point back it off until it is in a rest position and turn the opposing shaft (upper or lower on the same side) 90 degrees before proceeding.

 

If the crank mark is pointing down you need to completely unload the cams before you can turn the crankshaft around to the timing mark.

Here's how to do that:

The boxer is a strange engine because you can set the cams in such a way that ALL of the valves are closed, this is just not possible on most other engines without completely removing the cams. Useful in situations like this when you need to turn the crank more than half a turn, you can close the valves completely and spin the crank without fear of bending any valves.

 

Starting with the crankshaft, make sure the mark is pointing straight down. (with the mark straight up or straight down the pistons are at half stroke and there is no way for them to come into contact with the valves) Now you can slowly turn each camshaft 90 degrees at a time until there is no spring tension on the cam. You'll know when this happens because they will become very easy to turn. And will turn easily through about 30 degrees or more of rotation by hand with little effort. The passenger side cams will be at or near their timing marks. The drivers side cams will be approximately 180 degrees off their marks. Once unloaded you can turn the crankshaft so the timing marks align. Then turn the camshafts to their marks. Only turn the drivers side camshafts 90 degrees at a time.

I hope all that makes sense.

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Thanks Su-bah.

 

My concern at the moment is that the RH intake and both LH's are unlifted, but the RH exhaust is lifted and the crank is not at its mark.  Since the manual section never discusses the proper rotation direction of the RH's, I was concerned which direction to turn the RH-Exh to get it properly unlifted.  So your initial description of the 1-5 o'clock and 6-12 o'clock rule would also apply to the RH cams?

 

Thanks Again, Steve

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The RH head is not under load so if you pulled the belt when the mark was lined up then making sure it's right it should not need much turning at all.

 

I was able to line up and pull the pin on mine and the cams all were still pointing at the right marks.. However my tensioner is going weak so it allowed the RH side to jump 2 teeth on the intake side.

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Hey Mike - As noted in my reply a couple posts up, we had the belt slip on us while tightening the LH cam sprocket bolts, so to avoid rotating the engine any further and incurring potential damage, we did not pull the belt with the marks lined up - we pulled it right where it was and decided to start over.  That's why the RH-Exh is in an unusual position.  I imagine a slight tweak will have it spring loose, but just wanted to be sure what direction to go with it.

 

Does that make sense?

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It does, I've had the LH head spring back if the belt teeth catch it good enough.. As long as you rotate the cams the right way to prevent valve to valve damange.. Once however when you do have them under no load (both cams not pushing down) then rotate the crank so the pistons are at BDC which it would be a line on the crank sprocket.

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Success! Got 'er done.

 

Fairtax4me's advice on re-setting the marks when all was askew was spot on.  Got every thing all buttoned up and the Legacy is running smooth.

 

Lucky for us we opened it up when we started hearing an idler bearing squealing or else it could have been catastrophe.  We found the toothed idler on the water pump with its bearings all chewed up and it also tore up the water pump flange and mounting bolt - surprisingly enough the belt never skipped a tooth.   So with the full kit installed we're in good shape.

 

Thanks all !

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  • 2 years later...

I just did a timing belt / water pump on my 98 Outback.  I was a little worried because I did not have the tool to lock the cams in place.  I found a cheap substitute that works great.  I used an Irwin 12" quick clamp.  The clamp is plastic and has rubber protective feet on it.  I just put the feet in between the two cam sprockets and tightened it up and it held while I took the old belt off and did all the other work.  The bar was in the way a little but not enough to really matter.  Hope this helps someone.

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