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420A Brakes won’t bleed on driver side

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Kevin-eclipse-rs

Probationary Member
11
0
Jan 1, 2023
Phoenix, Arizona
So I recently replaced my brakes on my (420a 98 Eclipse RS) and the passenger side bled correctly, no bubbles good pressure, but the driver side is a pain. Sometimes it gets pressure and comes out fluently no air bubbles then randomly I get a burst of nothing but air bubbles for days. I've cleaned the threads, put grease around the screw, and bought the pump to do it easier and still nothing. The brake master cylinder looks new and no leaks but if it did fail why would it fail now when I’m doing a simple break change.

off topic my Speedo doesn’t work but that’s because it’s missing the plastic thing what is that called. Or can I get a link on where to buy the wheel that goes on it thanks
 
off topic my Speedo doesn’t work but that’s because it’s missing the plastic thing what is that called. Or can I get a link on where to buy the wheel that goes on it thanks
You're talking about the VSS (vehicle speed sensor). By "the wheel" I'm assuming you mean the gear on the end of it? If that's missing it could be a bad thing. It might have fallen down inside your transmission. I haven't been able to find a new gear, and a replacement sensor does not come with the gear.

Your brake issue sounds like there may be a leak somewhere between your master cylinder and driver caliper, or internal issue with the master cylinder. I would check the proportioning valve as well (mounted on the firewall).
 
You're talking about the VSS (vehicle speed sensor). By "the wheel" I'm assuming you mean the gear on the end of it? If that's missing it could be a bad thing. It might have fallen down inside your transmission. I haven't been able to find a new gear, and a replacement sensor does not come with the gear.

Your brake issue sounds like there may be a leak somewhere between your master cylinder and driver caliper, or internal issue with the master cylinder. I would check the proportioning valve as well (mounted on the firewall).

I don’t think it fell into the transmission but unsure. I robbed one from the junk yard and it didn’t come with a gear either. I’ll check that out tomorrow. The master cylinder looks new which is why I find it weird that only the passenger side is bleeding correctly but I’ll check all the lines tomorrow too.
 
You're talking about the VSS (vehicle speed sensor). By "the wheel" I'm assuming you mean the gear on the end of it? If that's missing it could be a bad thing. It might have fallen down inside your transmission. I haven't been able to find a new gear, and a replacement sensor does not come with the gear.

Your brake issue sounds like there may be a leak somewhere between your master cylinder and driver caliper, or internal issue with the master cylinder. I would check the proportioning valve as well (mounted on the firewall).
So I have no leaks with the proportion valves no leaks on any of the lines so it may be an internal master cylinder or the break booster but I see no leaks with the break booster and when I was bleeding I saw chunks of black plastic with looked like the seal of some sort also when bleeding the driver side has little to no pressure in shooting out fluid it either bairly comes off the tip or none at all as of rn iv pumped it a couple of times and it’s bairly going up the tube to bleed
 
Have you replaced your 30 year old brake HOSES? They can and will collapse internally, and sometimes they won't pass fluid BACK out of the caliper so it will lock it up. When you mentioned black plastic, I am thinking the inside of the hose is deteriorated. I have had it happen to me is why I can talk about it first hand. My older car (67 Camaro) did lock up a wheel and I couldn't move it until I cracked the hose open and then the brake released. You might want to check yours. I replaced all of the rubber hoses on that car and fixed the issue.
 
I agree on hoses. At this point finding debris I’d be concerned of what might be inside the calipers. Consider replacing the hoses or at least disconnecting at the calipers and flushing with a full reservoir or two of fluid. I’d do all four corners, since you don’t know where the debris came from. Best practice would be the rebuild the calipers too. The kits are pretty reasonable, so it’s mostly just a time investment.
 
I agree on hoses. At this point finding debris I’d be concerned of what might be inside the calipers. Consider replacing the hoses or at least disconnecting at the calipers and flushing with a full reservoir or two of fluid. I’d do all four corners, since you don’t know where the debris came from. Best practice would be the rebuild the calipers too. The kits are pretty reasonable, so it’s mostly just a time investment

So the thing is my stock ones had broken bleeder valves so I went to the junkyard and got the front two I removed the piston checked if everything was good and it was no tears in the boot piston was good and clean so the calipers are good ima see if I can reset proportioning valve (not sure how) and clean up the lines see if it’s clogged or not
 
Have you replaced your 30 year old brake HOSES? They can and will collapse internally, and sometimes they won't pass fluid BACK out of the caliper so it will lock it up. When you mentioned black plastic, I am thinking the inside of the hose is deteriorated. I have had it happen to me is why I can talk about it first hand. My older car (67 Camaro) did lock up a wheel and I couldn't move it until I cracked the hose open and then the brake released. You might want to check yours. I replaced all of the rubber hoses on that car and fixed the issue.
I’ll check the hoses if there bad I’ll get new ones I wanna check if it’s the proportioning valve and reset it bjt I’m not sure if it’s possible I only see them on bigger vehicles or the ones that have the break switch on them
 
On DSM's, the prop valve splits 4 ways so each wheel has its own dedicated line. Just fyi.
These cars are old.
Brakes are IMPORTANT. :thumb:
I haven't personally seen a proportioning valve go bad.
 
You can’t really check the caliper hoses. You just replace them to rule them out if they haven’t been done.
If you are getting air after bleeding properly(3-4 pumps, hold, and have someone crack the bleeder, and hold down until they can tighten it again) then the system is open somewhere. Clean everything and then look for leaks.
 
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