: ls7 Clutch swap trouble bleeding clutch!!



D-RoKK
04-07-13, 11:49 PM
So I swapped in a ls7 flywheel, clutch, pressure plate, slave cylinder, also a 36" remote bleeder from monster. I also have a mityvac. I cant get ANY feel in the pedal and everything is connected and torqued down to spec. Maybe I'm just doing this wrong, but can anyone give me advice of how to do this or a procedure to bleed it?

Thanks!!

pato
04-08-13, 01:18 AM
I think you still have a lot of air in the system, keep bleeding until it comes up.

I started bleeding with a simple vacuum pump for about 30 minutes and was not getting any pedal.

I hooked up the bleeder in the link below and was done in 5 minutes. It requires an air compressor though.

http://www.amazon.com/Mityvac-MV6835-Vacuum-Brake-Bleeding/dp/B0015POUXM/ref=sr_1_3?ie=UTF8&qid=1365394529&sr=8-3&keywords=mityvac+brake+bleeder

D-RoKK
04-08-13, 01:25 AM
Damn 150? For that price I could have a caddy dealership bleed it haha. I have a simple hand pump one..

Ive been told to stay around 10-12 Hg of pressure. Do I just keep doing that until it wont do anything else? I dont want to pull any seals...

Is my clutch pedal going to feel like it should right off the bat?

pato
04-08-13, 01:32 AM
Yea, if you have a hand pump one, it's going to take a looooong time.
I think I was doing 20-25 psi with the hand vacuum pump for over a half hour and it got me nowhere.
I don't think you can pull any seals with what you're using. Keep bleeding.

D-RoKK
04-08-13, 01:54 AM
So im assuming that no more air bubbles will appear when I am to be done vaccum bleeding? Then do I just bleed traditional style? Or should it all be done with the vaccum?

Naf
04-08-13, 02:43 AM
i use pressure instead of vacuum, get the Motion brake bleeding kit, its from 50$

http://www.motiveproducts.com/

Works like a charm, and since you have the remote bleedin kit, its less moving around...

Bacon V
04-08-13, 11:34 AM
Did you make sure to close the check valve on the end of the remote bleeder when you were done bleeding? It should only take a few pumps to bleed it, close the valve, pump twice and feel your new firm pedal

D-RoKK
04-08-13, 11:39 AM
Hold on here, this is how ive done it..

Have the bleeder valve closed, stick the mityvac in the master, build pressure, relieve pressure and add fluid. Is that right??

Bacon V
04-08-13, 12:05 PM
Get rid of the mityvac, you won't need it.

Fill reservoir, pump pedal a few times slowly, top off reservoir, open check valve half a turn or so and put into a cup or container. Push clutch in and hold a couple seconds, release and wait a second, pump and wait, release, fill reservoir, pump and wait, release and wait, pump and wait, release, close check valve, fill reservoir, pump pedal and it should be firm. Repeat the pump, release, fill process until bubbles are gone.

In my experience, pressure from the pedal works better thana vacuum.

D-RoKK
04-08-13, 12:32 PM
So you release while its open?

Bacon V
04-08-13, 12:50 PM
If the bleeder has a check valve on it, then yes. It'll close as soon as the pressure drops at the end of the pedal travel

D-RoKK
04-08-13, 01:29 PM
It doesn't have a check valve... just called monster.

Jeff James
04-08-13, 01:46 PM
Put the end of the bleeder without check valve in another container with some fluid in it and keep the end below fluid level. Bleeding is only about moving fluid not pressure. Just move the pedal(don't pump) a few times and watch for air movement.
Another way might be to just have the end of your bleeder in the fluid and open it. Let it gravity bleed for a little while. The air will work it's way to the reservoir and out. Works with Brakes!!
Good luck

D-RoKK
04-08-13, 01:53 PM
Put the end of the bleeder without check valve in another container with some fluid in it and keep the end below fluid level. Bleeding is only about moving fluid not pressure. Just move the pedal(don't pump) a few times and watch for air movement.
Another way might be to just have the end of your bleeder in the fluid and open it. Let it gravity bleed for a little while. The air will work it's way to the reservoir and out. Works with Brakes!!
Good luck

Im thinking of gravity bleeding while im at work today which is a 3.5 hr shift. How can I make sure the master wont run dry?

Bacon V
04-08-13, 01:56 PM
Buy a check valve at the auto parts store for 3 dollars and thread it in the end of your line. Tick comes with a check valve on it.

D-RoKK
04-08-13, 02:04 PM
So thread it to my line then when I have my bleeder open the air won't come in right?

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How do I look up a check valve that would work for me on autozone or OReilly website?

Bacon V
04-08-13, 02:24 PM
Figure out what the thread size is on the line and then go to the store and ask for one. I can't find it on the website, but i know I've seen them at oreilly by the brake stuff. Looks like a standard brake bleeder nipple on one side and an npt thread on the other.

Bacon V
04-08-13, 06:11 PM
The thing circled in green is the check valve and it's what you should get. Its a one way check valve when open which allows fluid out and then closes to prevent air from getting in. When done, you just tighten the check valve into the female fitting like a regular brake bleeder fitting. Turns bleeding into a simple pumping exercise. Dont let the reservoir go dry or you have to start over.

106490

Jeff James
04-08-13, 07:10 PM
You DO have to keep an eye on it or it will drain completely. The check valve is a great way to do it but just opening the bleeder and keeping it below fluid in extra container will do the same. Just keep an eye on the reservoir when hand compressing the clutch.

D-RoKK
04-09-13, 01:19 AM
This just doesn't make sense! Ughhhhhh. So I had everything connected and transmission bolted to the bell housing. I have an ls7 flywheel, clutch, pressure plate, slave cylinder, and monster remote bleeder with a check valve. I had a friend tell me I needed an ls7 master cylinder. Is that correct? Because the current slave cylinder I just put in was getting barely any feel and then it just started leaking fluid out of the bell housing. It just doesn't seem right that mine im going through slaves left and right (5 now) and each time I get barely or no pedal feel and then it just leaks... I am so fed up with gm and it's design right now im about to pull out the ls2 and put in a ford v8 since their transmissions are so much easier to work with..

Jeff James
04-09-13, 02:02 AM
Just step away from the Ford, Man. Everything will be OK. Sounds like maybe something is loose on the Slave. I've been watching the LS7 clutch threads for some time and never heard these problems. The only real issue has been whether to use an LS7 slave or the LS2 with the spacer. You also may have a thread issue if you installed an NPT bleeder/check valve in the end of the AN hose. Straight thread vs tapered is always a problem. Go back to the bleeder as delivered and remember MOVE Fluid not pressure. The gravity bleed may work better. Air trapped inline won't move very far with each movement of the pedal. Try putting the bleeder -open- in the reservoir then compress pedal. You will be moving the same fluid thru and won't empty the reservoir.

D-RoKK
04-09-13, 02:17 AM
Can someone explain to me how a gravity bleed would work since the bleeder screw is on the top of the slave cylinder?

Jeff James
04-09-13, 02:31 AM
Hopefully air rises out of the system when the open bleeder is below everything else. I am the first to admit that I have not done this . Trying to help here. The bleeder bottle (container) or bleeder in the reservoir is the best way to bleed anything. Ever bench bleed a Master cyl. with bent tubes that just come back into the reservoir?

D-RoKK
04-09-13, 02:34 AM
Now explain what bench bleeding is. Ive heard it but have no idea what it is.

Is it possible I need a new master Cylinder??

If I gravity bleed, do I open my remote bleeder and stick it in fluid and leave it there?

Thanks!!

Bacon V
04-09-13, 08:11 AM
Typical...someone attempts their own repair and then blames GM when they botch it. No you don't need a ls7 master, but you do need an ls7 slave.

Mr.electric
04-09-13, 08:48 AM
Hydraulics can be a huge pain in the ass , frustrating experience. I spent like 5 -7 hours and a gallon of brake fluid trying to bleed the clutch on a ford ranger. Turns out the angle of the lines going into the master makes it impossible to bleed without taking out the master and allowing the air bubble to escape by making the line face up not down then reinstalling. I have been very pleased with pressure bleeders. With clutches I have noticed that simply working the pedal for about 15 minutes with the bleeder closed seems to work every time. Even on a camaro with an ls1 with the concentric slave. I mean just fill up the res, sit in the car and press the pedal in and out for 15 minutes. It has worked for me. By the way does the master mount at a 45 degree angle like the ford?

Bacon V
04-09-13, 08:54 AM
You said you've gone through 5 slaves and they all leak? Doesn't that seem odd? Where are they leaking from? Post a picture of your slave cylinder all we can see it. Where are you getting the slaves from? Are you positive it's an LS7 and not just a stock replacement? There is a big difference between the two.

Bottom line, if you've got leaks you've got a hardware problem somewhere and you'll never get a firm pedal. It's possible you have a bad master, but if it worked before this install then it likely still works.

Bench bleeding is just what it sounds like. Bleed the whole assembly on the bench while it's out of the car, and then install without disconnecting any lines.

PISNUOFF
04-09-13, 09:10 AM
If you aren't getting any pedal pressure after you bleed the system just pump the pedal up and down a bunch of times. This has happened to me many times, especially with new parts.

D-RoKK
04-09-13, 11:19 AM
http://i747.photobucket.com/albums/xx116/imjustsobeast/20130408_224525.jpg
http://i747.photobucket.com/albums/xx116/imjustsobeast/20130408_224747.jpg
http://i747.photobucket.com/albums/xx116/imjustsobeast/20130408_224555.jpg
http://i747.photobucket.com/albums/xx116/imjustsobeast/20130408_224544.jpg

I have gotten 2 from rock auto, 1 from concentric, and I have a total of 3 from OReilly for the exact purpose of fear they would leak. All for the ls7.

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Ive always been a ford guy.. ive had 2 mustangs (built a v6 auto to beat gt's and built a gt 5 speed centennial edition to run down cobras), then ive also had a f150.

Jeff James
04-09-13, 11:46 AM
You said you've gone through 5 slaves and they all leak? Doesn't that seem odd? Where are they leaking from? Post a picture of your slave cylinder all we can see it. Where are you getting the slaves from? Are you positive it's an LS7 and not just a stock replacement? There is a big difference between the two.

Bottom line, if you've got leaks you've got a hardware problem somewhere and you'll never get a firm pedal. It's possible you have a bad master, but if it worked before this install then it likely still works.

Bench bleeding is just what it sounds like. Bleed the whole assembly on the bench while it's out of the car, and then install without disconnecting any lines.


You can "Bench Bleed" on the car if your bleeder line is long enough to fit into your Master reservoir.

Bacon V
04-09-13, 11:52 AM
True, you can bench bleed on the car. Just make sure you retain the TOB with a clamp or something or you'll blow the piston out of the cylinder sleeve.

Where specifically is your leak coming from?

D-RoKK
04-09-13, 12:02 PM
I cant locate the leak per say, but it comes from inside the bell housing. Is there a way that when I have the transmission unstabbed that I can actuate the slave cylinder??

Mr.electric
04-10-13, 04:27 PM
Maybe the slave is over extending. Is the friction plate in backwards or some spacer incorrect? If the slave is leaking it may be pushing too far out.
Also I heard about a Honda where the clutch pedal bracket was cracked. It would never make pressure because the master was not traveling enough.
Would one of those cameras on a stick fit in the hole on the side so you could perk in there while someone press the pedal?

D-RoKK
04-10-13, 04:52 PM
Not sure, but its going to a transmission shop today to get bled. They'll figure out what is wrong for sure haha.

Mr.electric
04-11-13, 09:33 AM
I bet that shop redoes the clutch job and charges you $1200

D-RoKK
04-11-13, 09:43 AM
I bet not, I know what im doing just couldn't get it to bleed

D-RoKK
04-11-13, 04:48 PM
Does the ls7 master have a different connector than the ls2?

NC-V
04-11-13, 09:32 PM
No, the connector is the same LS2/LS6/LS7/LS3

D-RoKK
04-18-13, 01:13 AM
I had a bad master

Mr.electric
04-20-13, 08:20 AM
How much was the shop bill? Too bad we all missed the obvious possibility that the master was the culprit. I guess that's why shops usually replace them as a pair.

WesH8398
04-20-13, 11:55 AM
On this topic, is the master something that should be done with a clutch swap? The LS7 swap is in my distant future, but didn't plan on replacing the master cylinder as well... Do these fail often or at any particular mileage? Are there any telltale signs of wear?

D-RoKK
04-20-13, 01:33 PM
The shop charged me nothing and I do the work myself especially since I did an engine swap from 3.6 to 6.0

Mr.electric
04-21-13, 12:27 PM
Nice. Good shop to help you out.
I have heard of masters failing after being bled, moved or transplanted to another vehicle. I think a weak seal can go when the piston suddenly travels in air not fluid during bleeding. Plus all the silt from the bottom of the reservoir get pushed through.