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Bleeding the hydraulic clutch

chris57

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Seem to be having some trouble with the master cylinder and bleeding the clutch. Brakes bled fine but the clutch, master piston, wants to get stuck in the fully depressed position. I am wondering if the clutch systems wants to be full for the master piston to want to spring back. Maybe I need to back bleed the system from the bleeder valve? Thoughts?

Thanks
 
In my experience, if it is a bleed issue, the clutch won't disengage when you depress the pedal. It sounds like you have the opposite issue. When bleeding the clutch, I bleed it at the slave cylinder end. There is a bleed screw that you can access through the right side footwell behind one of the rubber plugs. Invest in a MitiVac, it will make your life a LOT easier while bleeding. It took me two shots to get the clutch bleed correct, as there was one air bubble that was particularly stubborn to make its way out.
 
I need more information Chris:

Exactly which model car do you have. There are no less than 4 or 5 different possibilities.

Is this a cast iron combined unit from an early car or one of the later separate units?
If early, Disc brake or drum all around.

You should add your make and model to a signature line so we can always tell what you have.
 
It sounds very much like you might have pitting on the inside of the master cylinder. I had exactly that symptom and ended up getting a new MC.
 
Hi,

Where do I find the "Signature Line". Sounds like a good ides to add that info.

I know I do have some pitting in the cylinders. And that may drive me to buy a new MC. I'm going to try the Mitivac first.

Regarding the vehicle I'm working on.

The MC is the cast combined unit. Disc in front, drum on the back.
 
Click on you userID (Chris57) on the left side of your message, then select "View Profile", and then "Customize my Profile". You'll see a place to add a signature.

I suggest you consider having your original sleeved and having the bore resized to 3/4" if you have disc brakes. This is the correct bore size for a disc brake conversion. Your brake pedal effort will be reduced by 33% and you clutch action will also noticeably improve. This is a much better solution to buying an aftermarket one and will outlast a reproduction unit tenfold - you will never have pitting problems again.

This is a service I have been offering for over 10 years with excellent results. You can contact me directly if this interests you and want more details. A couple sample restored units pictured.

WP_000786.jpgWP_002674.jpg



Hi,

Where do I find the "Signature Line". Sounds like a good ides to add that info.

I know I do have some pitting in the cylinders. And that may drive me to buy a new MC. I'm going to try the Mitivac first.

Regarding the vehicle I'm working on.

The MC is the cast combined unit. Disc in front, drum on the back.
 
I second Gerard's suggestion on sleeves. I have had it done to several cylinders. I don't have any of his yet because they were all before I knew him and I can't wear hem out. He will sure get the next I have to do though.
 
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