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Advice on loosening/tightening camshaft bolts (1999 2.5L Legacy)


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The saga continues.... my timing belt project is turning out to be a real disaster.

 

I bought a timing belt & water pump kit that included crankshaft & camshaft seals, and figured it was a good idea to replace them while I was at it. I tried a couple of methods to get my camshaft bolts loosened, since I didn't have the special tool. After tongue & groove pliers, a strap wrench, and a cheap plumbing wrench failed me, I managed to lock up the left-side camshafts by folding my old timing belt over a couple of times and wedging it in between the sprockets, such that the teeth on both camshaft sprockets engaged the belt. Piece of cake.

 

Right side didn't work so well. I tucked a small wedge in between the folds of the old timing belt that time, thinking it would make the job quicker, but it had the effect of shattering the exhaust sprocket before the bolt loosened. Stupid idea, in hindsight. I didn't realize how vulnerable the sprockets would be to this kind of stress.

 

I'm pricing out a new sprocket, but obviously I need a better way of tightening/loosening the bolts. I'm loathe to spend $60 or more on the specialty tool, since I don't know if I'll use it again on this car. I'd rather spend the same $$$ for a general-purpose tool that will serve me down the road. (That said, I'll gladly buy the specialty tool for the sake of doing it right, if no other tool will do).

 

I thought about a chain wrench, but nobody around me carries them. I need to make sure that (1) it is good quality, don't want to spend money on junk, and (2) it will fit between the intake and exhaust sprockets, with a leather belt or something in between for protection if necessary. Brand recommendations welcome. Or, is there another alternative tool or trick instead of a chain wrench?

 

Also---maybe a silly question, but why was this bolt so tight? Is it common practice to use a strong threadlock compound for them? If not, I have to assume someone before me tightened the everliving crap out of it. The torque I applied trying to loosen it greatly exceeded 60 ft-lbs.

 

Thanks as always for your kind advice. I know some of my issues are probably pretty cringeworthy newbie material. :-)

 

 

 

 

 

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I always lock up the cams by using the old belt and taking it around the crank and the cam pulleys and putting a vice grips on the belt in the middle.  

 

I do this on the SOHC engine but I believe it would work on the quad cams as well.

 

Use the old belt so you don't damage the new one.

Edited by lmdew
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I would check the pull and pays for the sprocket, yes , a lit of people use thread lock on those and the crankshaft bolt. As far as a tool, I seen a photo somewhere that a guy took a 2x4 or maybe was a 2x6 and drilled holes to match the holes in the sprocket and put bolts through board just like the tool would be. For loosening the bolts, I wouldn't hesitate to use an impact to remove them, do NOT use it to tighten as I'm sure you have enough sense not to.

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You can also get the $5 chain wrench from harbor freight, wrap the pulley with part of the old belt, and use the chain wrench to hold the pulley steady while you loosen the bolt.  Of course, you could also have loosened the cam bolts before taking off the timing belt, which is what I do, but you would still need the chain wrench and old belt to tighten the bolts when you reassemble.

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I always try to crack them loose before removing the old belt. Sometimes it doesn't work out though. The teeth just skip. Same with tightening. If you tighten them after installing the new belt you chance having them skip a tooth or more out of time.

Wrap the old belt around the sprocket and around the crankshaft, then use vice grips, c-clamp, etc to hold the belt. Reverse the direction of the belt on the sprocket when you want to tighten. This seems to work best in the absense of special holding tools.

 

The FSM spec is around 60 ft-lbs, but they've been on there in the same place for years, and thousands of heat cycles. The threads conform to each other, and the head of the bolt does the same with the flange on the sprocket. There also tends to be a bit of rust/corrosion over the years, due to moisture, dirt, dust in the air, etc. and if some one put thread lock on it at some point (not necessary), the effects add up to needing quite a bit more torque to break the bolt loose than what it should have been originally.

A Honda crankshaft bolt is a good example, if you've ever tried to crack one of those bastards loose.

 

Ive put bolts on with a small 3/8" ratchet and had to use much more force than I used to tighten them in order to crack them loose again 5 minutes later. So there are many more factors that determine how much force is necessary to loosen a bolt than just how tight you put it on.

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If it's an auto and the belt is still there, the easiest way to pop the crank bolts is to put the screwdriver through the bolt hole on passenger side above axle. this will prevent the engine from turning and be a piece of cake.

A manual will need some sort of strap wrench, or a 12mm 6pt socket on a 3/8 breaker on the flywheel bolt. Turn engine till the bar rests against the housing and go as above.

 

O.

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I had similar problems both times my wrx (d25 heads) blew up, also recently with a ej253. Some come out like cake with the old belt and the car in 5th gear or the vice grip trick... But some I've hit with 300-400ftlbs and they didn't budge at all. I think they get over tightened by the motor itself over time.

 

The first time I had the wrx apart, after stripping the old belt and breaking 2 cam gears/2 hex bits/snap on breaker bar... I bought a cam holding tool online, waited a week for it to arrive, then it broke on the first bolt lol. Took the longblock to a local machine shop and they stripped 2 bolt heads and then wanted more money than I was willing to give to work on it further.

 

::shakes my fists in the air damning Pleiades::

 

So after 10+ stubborn cam bolts... my failure-proof solution now is drilling the center of the bolt heads to relieve the tension. Drill a pilot hole with something small to keep the hole straight. After each drill bit size, try breaking it loose (10mm was my sweet spot yrmv)... it will either come out or the head of the bolt itself will break off as you increase bit size. Later model ej's should have hollow cam bolts, no idea what years but all mine were. No drill out kit needed. I had the best results with a 90 degree drill chuck and a handle, doing it with a drill press/mill would obviously be ideal but not practical.

 

Disclaimer: Be VERY careful not to hit threads or you will jack up your camshaft. You do not need to drill very deep at all. Just enough to relieve the tension of the head or to drill the head off. Inspect a new cam bolt beforehand to confirm the depth needed to free the bolt head and mark your depth on the bit with something (tape/grease pen).

 

 

 

The other trick is to weld a larger nut to the bolt head and hit it with a proper rattle gun. I remember seeing a video by outfront motorsports doing this. I'll dig it up.

 

Dug it up:

Edited by Ibreakstuff
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for the chain type vice grip - this one - Irwin chain vice-grips

 

I have these and they do work very well in most cases (not all) - the chain is about the same thickness as a bicycle chain. use a piece of the old belt wrapped around the sprocket to cushion/protect it.

 

breaking the bolts loose before removing the old belt usually works best, but again, not always. And with the plastic sprockets on the 2.5, i suspect it isnt that uncommon to have them break

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this thread is good - and frightening.

 

my situation on my 06 wrx is, I 'should' be doing the TB probably next fall or the spring after that, based on the 105 MONTHS part of the schedule (picked my car in Oct. of 05) - but the car is just now at 50K MILES.

 

would you guys replace the cam seals? the car will be under 60K miles when I do the TB work. I wasn't planning on cheaping-out with anything else, including putting in a new water pump (Aisin) but, I don't know if cam seals are a weak spot, or if I need to pull the oil pump and re-seal/tighten the back like I read about on older soobs.

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@heartless, thanks for the recommendation. Looks like just what I would need.

 

@1 Lucky Texan, I am not the expert here, but I can't help feeling like the sprocket design on mine (the Legacy 2.5L DOHC) could have used improvement. Those hex flats are nigh impossible to grip without the special tool, and as has been mentioned, these are made of plastic (or some kind of newfangled lightweight space-age material that breaks like plastic and cuts your hands like metal). Maybe later models & years have improved designs? If the sprockets on your WRX are made of metal or have a different way to grip (holes etc.) then they may be far easier to manage than these ones....

 

Thanks again everyone.

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The plastic sprocket are made of some kind of Fiberglass re-inforced Nylon.

Pretty common and they use it for pretty much everything in cars these days. Sprockets, valve covers, intake manifolds, engine mounts, even bumper support beams.

It's light weight and strong enough to do the job, it just doesn't always stand up to the twisting type force applied to it when trying to loosen the bolt because of the way it is designed.

 

 

Texan, go ahead and replace the cam seals. Even with low mileage they're 8 years old, and age takes a greater toll on rubber seals than mileage does. There are plenty of 8 year old soobs out there with 150,000 miles or more, and I'm sure most of them are on original seals.

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The plastic sprocket are made of some kind of Fiberglass re-inforced Nylon.

Pretty common and they use it for pretty much everything in cars these days. Sprockets, valve covers, intake manifolds, engine mounts, even bumper support beams.

It's light weight and strong enough to do the job, it just doesn't always stand up to the twisting type force applied to it when trying to loosen the bolt because of the way it is designed.

 

 

Texan, go ahead and replace the cam seals. Even with low mileage they're 8 years old, and age takes a greater toll on rubber seals than mileage does. There are plenty of 8 year old soobs out there with 150,000 miles or more, and I'm sure most of them are on original seals.

 

If they aren't changed, and beginn seeping/leaking, does it just folow the block down the front or does it get on the TB and screw things up?

 

what about the front crank seal?

Edited by 1 Lucky Texan
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Front crank seal is very easy there Texan and always a food idea to remove the boil pump and doubly check / tighten those screws on the back side. New o'ring while your there and reseal it to the block with anaerobic sealant. That seal is very easy to do ! I totally agree to the fact age plays more hurt to seals more than a seal that's in use and constantly being oiled and kept limber so to speak. I know I say this constantly, but its so much better to do everything there is to do to anything accessible when on a certain part, on the other hand you have some say, if it isn't broke , don't fix it. I take the approach of being proactive, preventive maintenance means more to me. Old saying right, an ounce of prevention is worth a pound of cure ;)

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Texan - depends on how badly they start leaking as to whether or not the leaking gets to the belt...on my first Subaru timing belt job (89 GL with EA82), I didnt do the seals and paid the price about 2 months later having to do it again because the oil leaks were bad enough to cause damage to the belt - it ended up with several teeth sheared off one belt because of oil damage, and left me stranded on the side of the highway on a cold winters day. Lesson learned the hard way.

 

To me, it just makes sense to do it all while you are in there and be done with it for the service interval - especially so with an interference motor. Why skip doing something to save maybe $20-30 and a little extra time, when it could end up costing you much, much more down the road?

 

as for the pulleys/sprockets...older models had metal. newer models all have the plastic/fiberglass composite type - done mostly for manufacturing cost savings... It is much cheaper to produce the composite parts than to produce the cast metal versions.

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