Slave Cylinder

[Rodney Shelast]

I am looking to bleed slave cylinder, as first step, for SV Alpine ('66) as clutch not functioning. It also se like the OD won't disengage as 3rd & reverse won't click into gear..I've read threads regarding slave & many reference slave cylinder located at transmission housing, however, isn't that in reference to OD solenoid ? Slave in my car is located on LHS of firewall. How do I go about getting into slave to bleed screw ! Thanks all...

 

[hartmandm]

Here is a picture of the clutch slave on my series V. The slave is below the starter. Bleed screw is directly above the hydraulic pipe connection (or at least it needs to be on top to bleed properly). Also pay attention to which side of the bell housing it is mounted. It needs to be on the backside, as in the photo.



Mike

 

[Rodney Shelast]

Thank you, I'm going to check this out hopefully today..But, in order to get to bleed screw, do I need to disassemble the housing or is screw in plain sight...Thanks again..

 

[Rodney Shelast]

Photos: left: underside of car - driver side - slave cylinder ? right,: clutch fluid container. Seems that the slave cylinders are everywhere on these models. Photo on left, is the black end piece the "dust cap" ? Assuming this is where I would find the bleed screw to bleed clutch system..Certainly appreciate all & any advice..

 

[Rodney Shelast]

Better photo of slave...

 

[hartmandm]

The bleed screw is circled. That is a black rubber dust cap on the bleed screw. You can probably pry it off with your fingers.


The clutch hydraulics came from the factory with brake fluid - DOT 4. Do you know what is currently in your car? You'll want to use the same fluid as what is already in the system. If you don't know what is in the system, but it is clear, go with DOT 4. In the unlikely event the fluid is a purple color, then I'd assume it was converted to silicone fluid. You can't mix DOT 4 and silicone.

FYI, below is the clutch master cylinder:


The clutch master cylinder doesn't push very much fluid when the clutch pedal is depressed. As a result, you might need to use a vacuum pump on the slave bleed screw to get enough air out of the system before you can use the clutch pedal to do the final bleed.

Mike

 

[Rodney Shelast]

This is very welcome info, thank you so much...As far as I know there is DOT 3 SAE J1703 in main cylinder, I checked on a few sites to see if collaborated with SAE spec.702.3 as outlined in Rootes WSM & checked out. So the large black cap is on opposite side of bleed screw then.?.No need touch that then...I don't have vacuum tool, is this be a problem ?

 

[Rodney Shelast]

In addition, does any of this procedure have any effect on the OD ? I'm having issues there as well, it won't disengage..If clutch gets to working properly would OD issue be remedied as well ? Thank you...

 

[hartmandm]

Fixing the clutch won't have any impact on whether the OD works or not.

The black cap is attached to the bleed screw end. You need to remove the black rubber cap from the bleed screw so you can attach a hose to the bleed screw and collect the brake fluid into some container during the bleed process. You need to use a clear hose to monitor if any air is getting pushed out of the system while bleeding.

If you have a small amount of air in the clutch system, then you can bleed using the clutch pedal and you shouldn't need a vacuum pump. Make sure the fluid level in the clutch master reservoir does not get too low or air will get sucked into the system and you'll have to start the bleed process over.

I've never checked current brake fluids against any Rootes specs. I've always used Castrol DOT4 and push some fresh fluid through the clutch and brake systems once per year to evacuate any moisture that might have accumulated. You can mix DOT3 and DOT4 without issue. If you have been using DOT3, I'm not aware of that being an issue. I think DOT3 specs might have a lower boiling point than DOT4 specs.

Mike

 

[todd reid]

I believe there are documented cases of DOT3 fluid attacking the rubber seals in Sunbeam hydraulic systems, so DOT4 would be the way to go.

 

[Rodney Shelast]

In Manual I know it does mention issues using improper fluid as erodes washers & such...I hope to begin bleed tomorrow...Wish me luck ha ha

 

[pruyter]

It looks to me that your bleed niple is at the wrong place, it should be above like Mike has mentioned.

Regards,

Peter

 

[hartmandm]

I think the photos are inverted. I see the bleed screw is closer to the starter than the hydraulic pipe, so I think the clutch slave orientation is ok - the bleed screw is above the hydraulic pipe connection.

Mike

 

[Barry]

I believe there are documented cases of DOT3 fluid attacking the rubber seals in Sunbeam hydraulic systems, so DOT4 would be the way to go.

If anything, it is the other way around.

DOT 3 (aka, SAE 70R3) brake fluid was the automotive standard from the late 1940's until the mid 1980's when DOT 4 was introduced and it took another 20 years (mid 2000's) for DOT 4 to become the industry standard OEM brake fluid for U.S. made cars.

DOT 3 brake fluids are a blend of glycols and glycol esters. DOT 4 brake fluids are a blend of glycols and glycol esters plus borate esters which raise the dry / wet boiling points.

The original SBR (Styrene-Butadiene Rubber) hoses and seals used in Series Alpine brake systems were compounded to be resistant to DOT 3 brake fluid, but may not stand up to DOT 4 brake fluid which contains borate esters. I am not aware of any definitive studies showing that DOT 4 brake fluid causes hoses or seals rated for DOT 3 brake fluid to fail, but the possibility cannot be ruled out.

 

[Rodney Shelast]

I think the photos are inverted. I see the bleed screw is closer to the starter than the hydraulic pipe, so I think the clutch slave orientation is ok - the bleed screw is above the hydraulic pipe connection.

Mike

I'm not sure what mean by inverted ha ha the photo was taken from under the car, where you'd circled bleed screw this is where I am concentrating on correct ?

 

[hartmandm]

Yes.

 

[puff4]

It’s now a long time ago, but Tiger Tom wrote a very good article on this. Here’s a summary:

K24 – Exploring Brake Fluids and Seals – TigersEast AlpinesEast

www.teae.org

 

[Rodney Shelast]

I'm not sure what mean by inverted ha ha the photo was taken from under the car, where you'd circled bleed screw this is where I am concentrating on correct ?

What is fluid capacity of SV master cylinder ? If bleeding slave clutch how much fluid would be considered maximum throughout the system...Thanks...

 

[Barry]

What is fluid capacity of SV master cylinder ? If bleeding slave clutch how much fluid would be considered maximum throughout the system...Thanks...

IIRC, the factory clutch master cylinder reservoir holds about 1.5 fluid ounces. The clutch master cylinder and clutch slave cylinder are both about a quarter fluid ounce and the 1/8" line connecting the clutch master cylinder and clutch slave cylinder is about another eighth of a fluid ounce for a total system capacity of about 2-1/8 fluid ounces.

Note that fluid ounces are a measure of volume rather than weight and it that it will take a LOT more than two fluid ounces of brake fluid to properly bleed the clutch hydraulic system. A pint (16 fl.oz.) should be enough, but flushing a hydraulic clutch system is an inherently wasteful process.

Also note that DOT 3 / 4 / 5.1 brake fluid is a very effective paint remover.

 

[Rodney Shelast]

Thank you is great info ! Leads me to have couple of questions: 1. In order to ensure entire clutch system contains proper amount of fluid (2 1/8 Oz's.) throughout, what is the process to pressurize system ? 2. The hole in the mid part of reservoir, is this the maximum capacity, or, should fluid cover hole during the bleed process ? Appreciate your comments...