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My turn to adjust valve clearances :)


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Didn't read the whole thread. Lash on these is simple to do. Can be done with engine in the car-pop motor mounts loose and jack one side up and set on a block of wood and set other side down. I always set lash .001 loose because it makes absolutely sure valves close. Downside is slightly noisier valvetrain but much safer for high revs/high heat and also allows for slight mileage stretch.
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Didn't read the whole thread. Lash on these is simple to do. Can be done with engine in the car-pop motor mounts loose and jack one side up and set on a block of wood and set other side down. I always set lash .001 loose because it makes absolutely sure valves close. Downside is slightly noisier valvetrain but much safer for high revs/high heat and also allows for slight mileage stretch.

 

Not sure how it's easy to do given if the valve is already out of spec it requires a new bucket

 

 

Indeed, I am doing the job with the engine in. So far, I have not had to pop the motor mounts loose. And yes, FSM says for instance exhaust clearance should be 0.35mm. I will be shooting for probably 0.36 or 0.37mm.

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New buckets will need to be involved. ;)

 

I can't get anyone to try my budget method. No new buckets required if you're increasing clearance (reducing bucket height).

BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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alright. Last night, I successfully removed the camshafts without even dropping any of the buckets :cool:. Cleaned up the buckets (they look great and shiny by the way), and will soon make some measurements. In any case though, the bucket that was in the 'no clearance' exhaust valve in #2 shows '476'. If that thickness is still accurate, I would need a 443 bucket, which is one of the smallest sizes shown in the FSM! I'll update later on exact sizes that I need, but I have a feeling I will have to buy them..
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Sounds like a plan.

 

Although the fact that you are needing one of the smallest size buckets might be a warning that perhaps the valve itself might need replacing at some point. Don't get me wrong, in this circumstance I'd get the clearance within spec and put it all together. But at some point in the future, that valve itself may need some attention.

 

There's an odd thing that seems to happen with our valves. They sort of deform like a flower that closes slightly, possibly due to excessive heat(?) And it seems to be a slow progression rather than something sudden. When this happens, it effectively makes the valve longer from stem tip to seat area, and that reduces clearance. Here's a post that best describes this phenomenon.

 

Anywho, don't mean to be a downer, just sayin.

BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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I totally understand your point (I actually read your thread yesterday again). And I was actually thinking about that too, when I noticed that I need one of the smallest size bucket. But yeah, for now I will button up everything and monitor that car like crazy.
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I didn't take any close pics unfortunately. Camshaft journals seemed good enough for 130k miles. Not perfect, some light scoring, but couldn't feel that by scratching my fingernail on it.
BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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I can't get anyone to try my budget method. No new buckets required if you're increasing clearance (reducing bucket height).

 

Can top the valve stems to increase clearance. True high performance engine rebuilders top all of the valves so they can use all the same size buckets. Never an issue with buckets then. :)

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Can top the valve stems to increase clearance. True high performance engine rebuilders top all of the valves so they can use all the same size buckets. Never an issue with buckets then. :)

 

That's true, and actually somewhat common. However the bucket modifications don't require removal of the head, disassembly of the head, purchase of new headgaskets, reinstalling the heads, torquing the bolts, etc. It's definitely a low-budget method :)

BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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alright. Last night, I successfully removed the camshafts without even dropping any of the buckets :cool:. Cleaned up the buckets (they look great and shiny by the way), and will soon make some measurements. In any case though, the bucket that was in the 'no clearance' exhaust valve in #2 shows '476'. If that thickness is still accurate, I would need a 443 bucket, which is one of the smallest sizes shown in the FSM! I'll update later on exact sizes that I need, but I have a feeling I will have to buy them..

look heurberger. they have more buckets listed than the FSM.

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Sounds like a plan.

 

Although the fact that you are needing one of the smallest size buckets might be a warning that perhaps the valve itself might need replacing at some point. Don't get me wrong, in this circumstance I'd get the clearance within spec and put it all together. But at some point in the future, that valve itself may need some attention.

 

There's an odd thing that seems to happen with our valves. They sort of deform like a flower that closes slightly, possibly due to excessive heat(?) And it seems to be a slow progression rather than something sudden. When this happens, it effectively makes the valve longer from stem tip to seat area, and that reduces clearance. Here's a post that best describes this phenomenon.

 

Anywho, don't mean to be a downer, just sayin.

 

can't find the post, however, it was suggesting the sodium filled valves can lengthen at high rpm?

 

looking at that link, the burned valve looks like it was ground differently than the rest. the angles are off compared to the rest.

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Measurements are in (see below)

 

A few questions:

1. I am shooting for 0.37mm clearance for exhaust side instead of 0.35mm. Good choice?

2. Shooting for 0.21mm clearance for intake side instead of 0.2mm. Or should I even go to 0.22mm since the max clearance is 0.24mm?

3. Two of my intake valves have actually extra clearance (see 'cyl 2 intake F' and 'cyl 4 intake R'). Do you think it'd be OK to leave them as is, or will it really lead to extra wear on valves, valve seats and cam lobes?

 

Really tempted to do heiche method here....

 

 

http://legacygt.com/forums/attachment.php?attachmentid=211620&d=1435376078

valve_clearance_measured_buckets.thumb.png.29c8e0caa0bf044810fc9cc9485677e9.png

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I can't get anyone to try my budget method. No new buckets required if you're increasing clearance (reducing bucket height).

 

Your method will work BUT the buckets have a convex finish on the center button because they have to rotate to maintain oiling on them. If you grind that off and the valve top isn't perfect, then they may not rotate as necessary.

 

I agree that it would definitely be easier and save money and if you were going to do that on a full build, you could grind the valve tops before assembly to have a convex tip and then grind the buckets any way you wanted and it would work just as well. :)

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