Tonyrodz's Tahoe Build Thread

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adventurenali92

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A few years back I had a leak at the master cylinder that was pretty bad. But we couldn’t tell if it was leaking from the master cylinder side or the hydro boost side. Close mechanic friend suggested I replace both since there was no point in replacing one only to find the leak was coming from the other and have to do it all over again so I went ahead and did both MS and hydro post unit and it hasn’t leaked since. I’d imagine if you’re in there to replace a master cylinder if that’s what’s leaking, you may as well do the hydro boost upgrade since it all has to be part anyways.
 

Rocket Man

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Check all your brake lines front to back, look for any pinhole leaks- if there’s any, there will be evidence of brake fluid. If there’s a pinhole in a rusted line you’ll lose pressure slowly while holding the pedal down. It’s a good safety thing to do in the rust belt. Good to see you back in this thread @Tonyrodz !
 
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Tonyrodz

Tonyrodz

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...I was thinking of saying to pull the abs fuse to rule out the EBCM. Probably still worth a shot.

The more things you can rule out, the better chances of finding the issue.
Ever since I put in the new hub(non oem) I had messed around with the abs sensors on both sides. At the time I didn't know an aftermarket hub uses it's own sensor, and it won't take an oem sensor--so I don't have a sensor on that side--so my abs hasn't worked since.
 

89Suburban

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Ever since I put in the new hub(non oem) I had messed around with the abs sensors on both sides. At the time I didn't know an aftermarket hub uses it's own sensor, and it won't take an oem sensor--so I don't have a sensor on that side--so my abs hasn't worked since.
First I heard of this, no schist?
 
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Tonyrodz

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Well, I bench bled the master cylinder the other day, got all the air bubbles out. Installed it today--wasn't able to bleed the brakes yet--but the damn pedal still goes to the floor, and it barely stops. Same exact thing it did before changing the mc. Gonna bleed them tomorrow. I really hope that'll finally fix it. Anyone have any ideas? It's not leaking at any of the 4 calipers--or anywhere else that i can see. Everything is dry.
 
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Tonyrodz

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I had help bleeding the brakes. I was able to bleed 3 out of 4. Ds rear, bleeder wouldn't crack open and I didn't want it to break--you know how it goes. Other 3 bled fine. Pedal still yhe same--right to the floor. Doesn't stop any better then before. Funny--I paid a mechanic to fix a rear brake line--the one i couldn't bleed--it was leaking at the fitting. It's still leaking. I tried a few times, last time and i couldn't get it to seal correctly, that's why I paid someone else to do it.
438766-9500ee5fc4696756bce171facd491899.jpg
438767-6f748c6e7ba5fbc59bf226f824bebccd.jpg

Same crap. I'm not sure if this is the reason the pedal goes to the floor.
 
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Tonyrodz

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Ton, you have to get that brake line right otherwise its not going to build pressure. Thats your issue. Think like a blown out rusted brake line. Same thing, its just blowing right out the fitting instead of a hole.
I figured. I just fought a brake line--same situation but going into the abs in my Vic--I made up a new line and flared it because the old line was leaking. For the life of me I couldn't get it to stop leaking. I fought with it for a few months. Finally I got fed up and wrapped a bunch of Teflon tape where the flare met the fitting--IT WORKED!! Maybe I'll try to do that. I bet it's leaking the same way--where the flare meets the fitting. So i guess I replaced the mc for nothing. Anybody need a good master cylinder? Non hydroboost. Come get it.
 

strutaeng

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Yeah, I agree with @Fless . I've always heard you are never supposed to use Teflon tape on flare fittings. Also never supposed to use regular compression fittings on brake lines, in spite of what mechanic that looks like Hillary Clinton says...I can't remember the dude's name at the moment...?
 

pwtr02ss

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I figured. I just fought a brake line--same situation but going into the abs in my Vic--I made up a new line and flared it because the old line was leaking. For the life of me I couldn't get it to stop leaking. I fought with it for a few months. Finally I got fed up and wrapped a bunch of Teflon tape where the flare met the fitting--IT WORKED!! Maybe I'll try to do that. I bet it's leaking the same way--where the flare meets the fitting. So i guess I replaced the mc for nothing. Anybody need a good master cylinder? Non hydroboost. Come get it.
Try flaring it twice. Meaning, loosen the tool and tighten it again. I had a terrible time with brake line kit I bought for my C10. I ended up having to redo every flare. I didn't cut it off, I just installed the tool and gave it a second go. It worked fine after that.
 

OR VietVet

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Try flaring it twice. Meaning, loosen the tool and tighten it again. I had a terrible time with brake line kit I bought for my C10. I ended up having to redo every flare. I didn't cut it off, I just installed the tool and gave it a second go. It worked fine after that.
There is a talent to flaring the lines right. I ran a suspension/steering/brakes/alignment shop, at one time. People would walk in wanting lines made. I used to do them while they waited. I got to be real quick at it and good too. If I did them now, it would take a little time to get that talent back. Having the right tools helped a bunch.
 

Geotrash

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There is a talent to flaring the lines right. I ran a suspension/steering/brakes/alignment shop, at one time. People would walk in wanting lines made. I used to do them while they waited. I got to be real quick at it and good too. If I did them now, it would take a little time to get that talent back. Having the right tools helped a bunch.
One might say that you have a flair for the flare! :happy175:

I'll show myself out...
 
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Tonyrodz

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Try flaring it twice. Meaning, loosen the tool and tighten it again. I had a terrible time with brake line kit I bought for my C10. I ended up having to redo every flare. I didn't cut it off, I just installed the tool and gave it a second go. It worked fine after that.
I actually did this on my Crown Vic--didn't work. I had no idea there were so many different kinds of flares.
 
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