Subaru clutch issue

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My friend contacted me with a weird issue with his Subaru wagon. It's a 2011 Impreza, 2.5, with a manual transmission. He limped it into his driveway, but it's not driveable now.

The clutch pedal goes down to the floor, and won't come back on its own. It can be pulled back by hand.

We bled the hydraulic system, both at the clutch slave cylinder (thank you, Subaru, for putting it up top!) and the clutch master cylinder.

The fluid is a lot cleaner now, but there's been no improvement in operation. The gear lever still can't be shifted into gear with the clutch pedal depressed.

The rod coming out of the slave cylinder does move out against the lever when the clutch pedal is depressed. Is it enough, though? I don't know.

When I push slightly against that lever by hand, with engine idling in neutral, I can hear a grinding noise starting.

I presume there is a problem with the clutch's hydraulic system, or else the pedal wouldn't stay depressed. If the clutch master or slave cylinder failed internally, would that cause these symptoms?

Thanks all - I'd appreciate hearing your thoughts on this!
 
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Possibly a broken clutch fork. See if the clutch fork moves freely by hand, if it does that's the problem.

Sub fork.jpg


OEM_Clutch_Fork_Broken_Compilation.jpg
 
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That sounds more like a bad master cylinder, not building any pressure. Broken fork usually lets the slave cylinder over-extend until the piston comes out and it leaks.
 
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Sure it could cause the pedal to sink if its cracked, its possible. If the MC and slave check out the fork. See if you can move it by hand.

This leads me to believe there may be more to this than hydraulics but who knows it may be something in the clutch system like the throwout, you need to check it out.

When I push slightly against that lever by hand, with engine idling in neutral, I can hear a grinding noise starting.
 

Number_35

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Sure it could cause the pedal to sink if its cracked, its possible. If the MC and slave check out the fork. See if you can move it by hand.

This leads me to believe there may be more to this than hydraulics but who knows it may be something in the clutch system like the throwout, you need to check it out.
Thanks Trav, will do! I wondered if that grinding noise was the gears starting to mesh, or the throwout bearing. Will do more investigation over the next few days.
 
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35, it’s the clutch pressure plate that acts as a return spring for the hydraulic system so if you have a issue with the fork, pressure plate or say a collapsed release bearing then the pedal won’t return from the floor. Same symptoms as air in the hydraulic system.
 

Number_35

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35, it’s the clutch pressure plate that acts as a return spring for the hydraulic system so if you have a issue with the fork, pressure plate or say a collapsed release bearing then the pedal won’t return from the floor. Same symptoms as air in the hydraulic system.
Darn, didn't know that. Makes sense though. Trav's theory about a cracked fork seems very possible.

My friend said it felt a bit off, and the deteriorated very quickly, fortunately not failing completely until the car was in his driveway.

I presume the tranny has to be dropped to replace the fork.

Is it reasonable to drop the tranny only, or do the engine and tranny have to come out as a unit?
 
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I once owned a 2007 WRX with a 5 speed. I wrote about in on that I had to rebuild the clutch slave cylinder once on it. Stupid easy to do and solved the issue for less than $20 using the OEM Subaru kit I ordered at a local dealer.

The repair kit: https://www.subarudirectwholesale.com/oem-parts/subaru-slave-cylinder-repair-kit-30622aa0308a?c=Zz1jbHV0Y2gmcz1oeWRyYXVsaWMtc3lzdGVtJmw9MSZuPVNlYXJjaCBSZXN1bHRzJmE9c3ViYXJ1Jm89aW1wcmV6YSZ5PTIwMTEmdD0yLTVpJmU9Mi01bC1oNC1nYXM=

Old thread: https://bobistheoilguy.com/forums/threads/2018-subaru-outback.281231/#post-4613266
 

Number_35

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I once owned a 2007 WRX with a 5 speed. I wrote about in on that I had to rebuild the clutch slave cylinder once on it. Stupid easy to do and solved the issue for less than $20 using the OEM Subaru kit I ordered at a local dealer.

The repair kit: https://www.subarudirectwholesale.com/oem-parts/subaru-slave-cylinder-repair-kit-30622aa0308a?c=Zz1jbHV0Y2gmcz1oeWRyYXVsaWMtc3lzdGVtJmw9MSZuPVNlYXJjaCBSZXN1bHRzJmE9c3ViYXJ1Jm89aW1wcmV6YSZ5PTIwMTEmdD0yLTVpJmU9Mi01bC1oNC1nYXM=

Old thread: https://bobistheoilguy.com/forums/threads/2018-subaru-outback.281231/#post-4613266
Thanks, skyactiv - what symptoms did your Subaru have?
 
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I had a similar issue with an 01 Maxima 5spd. Something felt off with the clutch not returning correctly, I got about a half dozen more actuations out of it before it stuck to the floor without disengaging the clutch. Had it towed to my indy.

Ended up needing a hydrualic slave cylinder. All in all wasn't too expensive since I had AAA for the tow.

I didn't think of it at the time but I probably could have saved the tow by putting in 1st with the engine off and then hitting the key to get going and done a few rev matched shifts to get it to the mechanic. Since the clutch was stuck down it would have let me engage the starter.
 

Number_35

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That sounds more like a bad master cylinder, not building any pressure. Broken fork usually lets the slave cylinder over-extend until the piston comes out and it leaks.
I was able bleed it, though, so there was some pressure being generated.
 
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Thanks, skyactiv - what symptoms did your Subaru have?

Barley able to drive the car because I couldn't fully disengage the clutch at a stoplight, hard to shift, had a few grinds shifting all from not being able to fully depress the clutch.

Taking the slave cylinder part and repairing it is easy peasy and doesn't require special tools.

Bleeding the clutch will be the fun part. Find a good Youtube video on bleeding a clutch. Doesn't need to be vehicle specific. You should have a 25" hose and someone to help. He will probably need a 3/16" I.D. hose.
 

Number_35

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Barley able to drive the car because I couldn't fully disengage the clutch at a stoplight, hard to shift, had a few grinds shifting all from not being able to fully depress the clutch.

Taking the slave cylinder part and repairing it is easy peasy and doesn't require special tools.

Bleeding the clutch will be the fun part. Find a good Youtube video on bleeding a clutch. Doesn't need to be vehicle specific. You should have a 25" hose and someone to help. He will probably need a 3/16" I.D. hose.
I think we bled it successfully (though without fixing the problem). My friend was in the car. He would lift the pedal manually, I would ask him to depress the pedal, and I would open the bleeder with an 8 mm socket. The pedal would go down, pushing out brake fluid, and I would close the bleeder. He would then raise the pedal manually, and we'd repeat. Easy with two!

On my own, I would have a rubber hose running down into a container of brake fluid.
 
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My vote is on the fork, my friend had a similar vehicle with bad fork. He was lucky Subaru cover the labor and he purchase the fork only.

Car was very low miles like 8 years and ~ 65K
 
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Darn, didn't know that. Makes sense though. Trav's theory about a cracked fork seems very possible.

My friend said it felt a bit off, and the deteriorated very quickly, fortunately not failing completely until the car was in his driveway.

I presume the tranny has to be dropped to replace the fork.

Is it reasonable to drop the tranny only, or do the engine and tranny have to come out as a unit?
You remove the bell housing, transfer case and transmission as a unit, not a hard job.
 
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Seen many Subarus with a siezed up throw out bearing and / or the throw out bearing grind up the input shaft. If that happens there are save kits out there to sleeve the input (but the throw out is a different size so be aware of how to get another in the future if need be).
 

teh60

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I've never seen a cracked fork in a Subaru but it's a possibility. The way you described it I think you need a new clutch which would include a pressure plate, throw out bearing, clutch disk, and flywheel. How many miles are on the car?
 

Number_35

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Here's a photo of the clutch slave cylinder and the top of the fork:

20220306_163102.jpg

I've never seen a cracked fork in a Subaru but it's a possibility. The way you described it I think you need a new clutch which would include a pressure plate, throw out bearing, clutch disk, and flywheel. How many miles are on the car?
I forgot to ask - I think around 200K km (125K miles).

My friend bought it just a few months ago, so it's hard to know how it had been treated previously.
 

teh60

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Here's a photo of the clutch slave cylinder and the top of the fork:

View attachment 91836

I forgot to ask - I think around 200K km (125K miles).

My friend bought it just a few months ago, so it's hard to know how it had been treated previously.
If you can push on the fork with the engine running and in neutral and hear a grinding noise that sounds like a damaged throw out bearing and/or pressure plate. Another thing you can do to verify the problem is remove the slave cylinder then remove the rubber boot around the fork and look down into the bellhousing and see if anything looks damaged. The way you described it, it sounds like you need a clutch. The reason for your hydraulic problems is because the slave cylinder has to travel too far for the fork and throw out bearing to apply the pressure plate. Hope this helps.
 
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