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rjp98outlook

valve clearance adjustment without special tool

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Hi. I have a 98 Outback, 114K, and I am presently changing the timing belt and tensioner. I am thinking this would also be a good time to adjust the valve clearance. (Solid lifters, DOHC.) I have heard that some people have been able to accomplish this with the engine in the car and without using the special Subaru tool 498187100 to compress the spring to get the shims out. If anyone has done this, could you please explain how it can be done.

 

Thanks very much

 

Rich

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Well, I didn't get any replies, but as an FYI, yesterday I did the job without the special compressor tool and it worked out fine. It taks a little longer, but it is definately possible. I replaced 9 of my shims. I only needed a few screwdrivers and needle nose pliers to replace valve shims with engine in vehicle.

 

 

Rich

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Rich....Tell me more..,please.

 

How hard is it ?? Are the shims easily identified ? Did the dealer have 'em all in stock ?..etc.....

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It is not a difficult job, but it requires patience and the ability to really embrace your vehicle in many interesting positions.:).

 

Yes, the dealer had all the shims I needed in stock. Basically here is what you do:

(1) Remove the valve covers (and all the stuff in the way)

(2) Remove the right side timing belt cover. (if you want to use this to aid in positioning of the valves according to the Haynes book. Saves a little time, but probably not worth it, yoiu can simply observe the valves directly.

(3) Turn the crank pully until some valves are at the lowest point on a cam.

(4) Measure the clearance between the cam bottom and lifter shim with a flat feeler gauge.

(5) Repeat steps 3 and 4 untill you have measured all 16 valves.

(6) The desired clearances are .20 mm intake and .25 mm exhaust. Any gap that

differs by more than about .02 mm should be reshimed. Go through your list

and see which ones exceed this.

(7) Remove the shims on the lifters for these valves only. I did this by using a large screwdriver to piviot against a rough part of the cam and push the lifter

bucket down by its edge with a twisting motion. The spring tension is not too strong this way. While holding the bucket is down, pop out the shim by pushing a very small screwdrived in the little side gap designed for this. Push it out of the way to make it fall to the ground, or grab it with needle nose pliers.

This method seems to work very well. You need to use a stubby screwdriver for the intakes to work from under the cam. The exhausts are a little easier to remove. (If there is more interest in this I will post greater details).

(8) Identify each shim by writing the valve number it came from on the back in marker.

(9) Go inside and make coffee. Measure the thickness of each shim with a micrometer, and based on this, calculate the desired thickness of the new shim that would be required to bring the clearance to desired clearance (either .20mm or .25mm).

(10) See if you can reuse any of the existing shims you are removing, and go buy the rest at the dealer (6.38 each).

 

To make things easier, I suggest converting feeler gauge measurements to mm right away and working entirely in mm rather than inches. You need resolution better than 0.001 inches idealy, so measure carefully even to the point of saying the clearance is in between guage sizes, i.e., 0.0095, etc. Remember that a single thousandth of an inch (0.001) is 2.5 shim sizes! There are 60 shims available in increments of 0.01mm.

 

Good luck

Rich

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Rich:

 

Thanks for posting your experience here. You mentioned replacing 9 of your shims... how far out of spec were they? And in what direction (less or more than spec)? Thanks.

 

I posted about this a while back, looking for info on the valve clearance adjustment, since I have 102,xxx miles on my '97 and it's due in the near future. I couldn't get consistent info from three local Subie dealers regarding the procedure, or cost of it, so I kind of just gave up for the time being.

 

Thanks for any further details you could provide.

 

Steve

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Steve:

 

Most of the clearances were smaller than spec, but 1 or 2 were larger. I think this engine must be in very good condition. The worst shim was off by about .002 inches (5 shim sizes). The engine has 114K miles. The worst exhaust valve had decreased from its ideal .010 to .008. I suppose it was a waste of time to do this job given how little the clearances were off, but you never know until you look, and it is recommended at 100K. I'll check again at 250K :)

 

RIch

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Has anyone ever stopped to think of how useful these forums are ? How in the world did we manage to get along before we had these things !!??!!

What makes it even better is when someone like rjp98outlook takes the time to respond in such detail.

 

My 2¢.

 

Hats off !!

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Agreed!

 

FWIW, I have my car in an indy shop right now, they're doing the wheel bearings on the FL wheel. I asked them about the valve clearance service, they said they don't bother doing it, he felt it not necessary. I think I'll have it done if the engine's out anyway, but probably not otherwise. On the other hand, I would be paying someone else to do this, these things are not DIY for me, I stick to easy stuff.

 

Steve

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great write up of your procedure. my 99gt wagon is approaching 90k miles and I was wondering if this was something that could be done in the driveway or not. sounds like it could but I willthink about whether it is really necessary at 105k per manual or better to wait till 150k or higher. the only time the engine has made a lot of noise was knocking around 60k and changing spark plugs fixed that. I would like to hear from more people that have done this or had it done by dealer or independent mechanic.

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From what I have heard, the potential danger in not adjusting valve clearance is not that the clearance will increase, but that it will decrease. An increase leads to noisy valves (tapping), but it won't kill you engine. A decrease, however, can be fatal. From what I understand from reading, as valve seats wear over time, the valve rises higher and higher in the head when it closes, and this means there is less and less clearance between the lifter shim and the cam lobe. This can begin to reduce the amount of time the valve spends closed in direct contact with the head. The problem is that this is the valves method of staying cool. It must conduct heat into the seat when closed. If your clearance ever gets to zero, the valve will not touch the head firmly at all and it will burn up. I hear this is particularly an issue for exhaust valves. I guess this is why they get .25 mm setting while intakes get .20. I would be happy to hear from anyone more experienced with this. Thanks. By the way, my 98 outback is running fine now with its new shims, timing belt, tensioner, and water pump. But it is still a noisy engine. Maybe I'll pull it out next year and rebuild completely (get those *()&(*&*&^ slapping pistons out!)

 

Rich

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I so here you. I pulled by 2.5DOHC and replaced it with a 2.2 EJ from a 99. Never had done much Subaru work before,so on a long holiday weekend to get it back on the road for Monday. I swapped my 2.5 heads on the 2.2 block. I just could not stand the piston slapp any longer(it was like my ex-wife- got noiser with age without any net benefit....)

 

If i had wanted a diesel I would have bought one.

Anyhow, I have a little noise on start up (maybe loose valve clearence?) a little rough idle at times but all in all I don't miss the 2.5 block.

 

Note: if I had an adapter plate to bolt the 2.5 intake on the 99 -2.2 heads I would have used them. They are a beautiful design, and easy to adjust. Easy I like.

 

I will try the adjustment,without the tool.

 

I too have found these forums priceless.

 

thanks to all who post.

 

 

Andrew

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dont mean to sound like an idiot but the bottom part of engine has 4 valves are these the exhaust valves and the top ones are intake and are the valve clearance the same on the sohc :popcorn:

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you got it - bottoms are exhaust - close to exhaust headers/manifold. and top are intakes - closest to intake manifold.

 

right - the valves get tighter with age.

 

i think 150,000+ miles is where clearances get too tight and burn exhaust valves - that's the biggest problem with these motors the exhaust valves.

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