1987 C4 Z51 Corvette - New Owner
- Thread starter JJTL
- Start date
- Sep 9, 2014
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had exactly same issue. i had both seized calipers (diagnosed from inability to push the caliper piston back in) and also my abs solenoid to front right was seized. if u search cf, there is a pretty easy way to pull it apart and clean the solenoids and that fixes it.
- Thread starter
- #43
Thanks for the kind words!
- Thread starter
- #44
Ok great, I will try and find the thread. I pick up the brake hose tomorrow morning. Cheap check to see if that is the issue. But I feel like I need to start learning how to fix and clean the ABS solenoids in the mean time lol.
Glad to hear that the ABS solenoids can be cleaned.
- Thread starter
- #45
Hi @VikingTrad3r I've done some searching on CF and not sure if I've found the right thread or not. Sounds like the ABS Modulator Pump is not very serviceable, but can be cleaned/flushed.
Do you recall the steps you took to clean yours by chance? My plan tomorrow is to pull the ABS Pump out, and then reverse flush the RF port with compressed air, and maybe brake cleaner. Hopefully blowing air through the RF port will dislodge any blockage, and pass it out through the MC front port on the ABS Pump. Also hoping that compressed air will be enough to do the job.
Any last minute ideas or advice you can give before I dive in tomorrow would be awesome!
Thanks,
Josh
- Sep 9, 2014
- 352
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here u go my friend:
Anti-lock (ABS) : Brake line blocked. My dissaembly. - CorvetteForum - Chevrolet Corvette Forum Discussion
C4 Tech/Performance - Anti-lock (ABS) : Brake line blocked. My dissaembly. - Hello everyone, (I try to write english as weel I can :flag:) My 86 Vette had front left brake blocked. I bought front brake caliper kit, and hoses. After that, the wheel was permanently braked and... absolutly no fluid...
www.corvetteforum.com
- Thread starter
- #47
Boom! Awesome, just what I'm looking for. You the man. Thanks!here u go my friend:
Anti-lock (ABS) : Brake line blocked. My dissaembly. - CorvetteForum - Chevrolet Corvette Forum Discussion
C4 Tech/Performance - Anti-lock (ABS) : Brake line blocked. My dissaembly. - Hello everyone, (I try to write english as weel I can :flag:) My 86 Vette had front left brake blocked. I bought front brake caliper kit, and hoses. After that, the wheel was permanently braked and... absolutly no fluid...www.corvetteforum.com
Here we go, about to jump into it.
- Sep 9, 2014
- 352
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BE VERY CAUTIOUS WHEN YOU REINSTALL THE BRAKE LINES INTO THE PUMP.
on reinstalling, you will want to keep the pump somewhat loose from its mounting bolts as you may need to wiggle or manipulate the pumps body as you attempt to thread the brake line nuts back in. once everything is properly threaded in you can snug them down.
please take pics!
- Thread starter
- #50
Happy Monday!
Thought I would share our progress on the ABS Modulator Pump. Had some good wins and overcame some hurdles. Attached are some pictures for reference.
Took about an hour to get the pump out of the car, not too bad. The driver side brake lines are a little tough as the access is more limited. The next obstacle was to get the cap off the main 12mm allan head bolt that holds the 2 ABS pump housings together. We found that we had to make a score or groove in the cap, and then this allowed us to finally pry it off. Thought we were all good from there, but turns out this main bolt is a monster to break loose! Maybe ours was just seized a bit. But we had quite a challenge to apply enough leverage to break it free. Ended up having to mount a vice to the bench, bolt the vice so it wont swivel, and then use a break bar with a floor jack handle as an extension. After about an hour or more, we were able to get it free.
Taking apart the ABS pump and cleaning it, actually went quite well. Pretty straight forward. We pulled out the 3 solenoids one at a time, taking care to remove the small screen, spring and ball bearing. Cleaning it all thoroughly and then reassembling it. There is a screen on both sides of the solenoid that we cleaned. Also took care to make sure the rubber o-rings are seated properly before reassembly. Went back together with no issues, as far as we can tell. We also blew air through the hard line from the ABS pump to the Right Front, just to make sure it wasn't blocked. Seems good.
So where are we now. We are stuck at the reinstalling it into the car stage haha. Of all the silly things, we cannot get the first brake line to thread back into the housing. It's a tough one to reach, so space is tight. Try to screw it by hand, but it gets stuck and as soon as we put a wrench on it, it pops out. Honestly, I understand if you don't believe me haha. Spent maybe close to 2 hours trying to get the first line on. Ended up calling it a night, before we ended up making something worse lol. Maybe we are being too careful not to stripe the threads. So that's where we are at now.
The one idea we have is to lubricate the threads and hopefully that allows us to get the nut started by handed further. If anyone has any tips or ideas we are all ears!
Thanks again to @VikingTrad3r for the info and thread.
Josh
Thought I would share our progress on the ABS Modulator Pump. Had some good wins and overcame some hurdles. Attached are some pictures for reference.
Took about an hour to get the pump out of the car, not too bad. The driver side brake lines are a little tough as the access is more limited. The next obstacle was to get the cap off the main 12mm allan head bolt that holds the 2 ABS pump housings together. We found that we had to make a score or groove in the cap, and then this allowed us to finally pry it off. Thought we were all good from there, but turns out this main bolt is a monster to break loose! Maybe ours was just seized a bit. But we had quite a challenge to apply enough leverage to break it free. Ended up having to mount a vice to the bench, bolt the vice so it wont swivel, and then use a break bar with a floor jack handle as an extension. After about an hour or more, we were able to get it free.
Taking apart the ABS pump and cleaning it, actually went quite well. Pretty straight forward. We pulled out the 3 solenoids one at a time, taking care to remove the small screen, spring and ball bearing. Cleaning it all thoroughly and then reassembling it. There is a screen on both sides of the solenoid that we cleaned. Also took care to make sure the rubber o-rings are seated properly before reassembly. Went back together with no issues, as far as we can tell. We also blew air through the hard line from the ABS pump to the Right Front, just to make sure it wasn't blocked. Seems good.
So where are we now. We are stuck at the reinstalling it into the car stage haha. Of all the silly things, we cannot get the first brake line to thread back into the housing. It's a tough one to reach, so space is tight. Try to screw it by hand, but it gets stuck and as soon as we put a wrench on it, it pops out. Honestly, I understand if you don't believe me haha. Spent maybe close to 2 hours trying to get the first line on. Ended up calling it a night, before we ended up making something worse lol. Maybe we are being too careful not to stripe the threads. So that's where we are at now.
The one idea we have is to lubricate the threads and hopefully that allows us to get the nut started by handed further. If anyone has any tips or ideas we are all ears!
Thanks again to @VikingTrad3r for the info and thread.
Josh
- Sep 9, 2014
- 352
- 361
Wow. I absolutely commend your work so far. Looks very clean. Well done.
So the issue you are having with getting all the nuts rethreaded is exaclty what I experienced. I spent at least 3 hours in futility. It was very VERY frustrating.
I had really hoped that the advice about not bolting it all down would allow you the wiggle room to wiggle the pump body as you rethreaded and you would avoid what i experienced.
So.....I assume that you tried un-doing all the other lines, and starting with your trouble line? I assume that you removed the pump body and inspected the threads to ensure that there is no crossing threading? If I recall correctly what eventually worked for me, was to remove the pump, find a thread pitch that matched, run it into first 4 or so threads to "clean them" and then when I put it back in i installed that one first, and the rest went in.
As long as you havn't forced it with a wrench and caused a cross, you can get this done. If I did reeeaaaalllyyy far back in my brain i think its possible that i used a thread tap that matched the thread to "clean" or "chase" the threads. Available in a kit at Canadian Tire or Amazon very cheap. But! Simply finding a bolt that matches the thread pitch would work too. You could take the pump into home depot and find the screw that matches, or look online at see what the thread pitch/size is for brake line fittings too.
You can definitely get it done.
So the issue you are having with getting all the nuts rethreaded is exaclty what I experienced. I spent at least 3 hours in futility. It was very VERY frustrating.
I had really hoped that the advice about not bolting it all down would allow you the wiggle room to wiggle the pump body as you rethreaded and you would avoid what i experienced.
So.....I assume that you tried un-doing all the other lines, and starting with your trouble line? I assume that you removed the pump body and inspected the threads to ensure that there is no crossing threading? If I recall correctly what eventually worked for me, was to remove the pump, find a thread pitch that matched, run it into first 4 or so threads to "clean them" and then when I put it back in i installed that one first, and the rest went in.
As long as you havn't forced it with a wrench and caused a cross, you can get this done. If I did reeeaaaalllyyy far back in my brain i think its possible that i used a thread tap that matched the thread to "clean" or "chase" the threads. Available in a kit at Canadian Tire or Amazon very cheap. But! Simply finding a bolt that matches the thread pitch would work too. You could take the pump into home depot and find the screw that matches, or look online at see what the thread pitch/size is for brake line fittings too.
You can definitely get it done.
- Thread starter
- #52
Great thinking on finding a matching bolt to clean the threads. We will do that.
Ya, we kept the mounting bolts very loose, and the first brake line we tried was the Front MC line which is the hardest to reach. So with no other lines attached, we are giving it the best shot. Not so much an alignment of the line issue, but more the threads just not wanting to cooperate. Doesn't look like we have cross-threaded anything, just doesn't seem to want to start.
Thanks for the feedback! Nice to know it's not just us haha.
We will take it slow and it will come back together eventually. Happy that we called it a night, and are taking time to regroup before attempting again.
- Thread starter
- #53
Well another update, and somewhat a request for ideas lol.
Before attempting to reinstall the ABS pump, I thought we hadn't actually tried blowing air through it to make sure it was totally clear and good to go. Turns out it's still blocked! The silver lining I guess, is that at least we didn't reinstall it.
Anyways, so far it has kicked our butt today. Spent about 3 hours on it. Throwing in the towel today, and try again fresh tomorrow. Everything is clear, except the RF solenoid. Can't get air through it. Screens are all cleaned. I even connected the solenoid to 12V and cycled it a bunch of times. I can feel and hear the solenoid click, so pretty confident it's working and not jammed.
So something is in the solenoid and blocking it. Not sure how it got by the fine screens, I guess it has built up. Our only idea so far, is to keep hitting it with brake cleaner and see if we can get it to seep in and dislodge something.
Open to other ideas! Always fun. Well we wont give up, but sure would be nice to solve this, this weekend.
Josh
Before attempting to reinstall the ABS pump, I thought we hadn't actually tried blowing air through it to make sure it was totally clear and good to go. Turns out it's still blocked! The silver lining I guess, is that at least we didn't reinstall it.
Anyways, so far it has kicked our butt today. Spent about 3 hours on it. Throwing in the towel today, and try again fresh tomorrow. Everything is clear, except the RF solenoid. Can't get air through it. Screens are all cleaned. I even connected the solenoid to 12V and cycled it a bunch of times. I can feel and hear the solenoid click, so pretty confident it's working and not jammed.
So something is in the solenoid and blocking it. Not sure how it got by the fine screens, I guess it has built up. Our only idea so far, is to keep hitting it with brake cleaner and see if we can get it to seep in and dislodge something.
Open to other ideas! Always fun. Well we wont give up, but sure would be nice to solve this, this weekend.
Josh
- Sep 9, 2014
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so u can get air through 2 out of 3 solenoids?
- Sep 9, 2014
- 352
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use some mild acid or something. id try that. and keep cycling the solenoid. tapping it? shock it? i realize how crazy that sounds with an abs unit.
- Sep 9, 2014
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- Thread starter
- #58
Ya could try shocking it. I can hear and feel the solenoid click, so I don't think it's jammed. Most likely tiny debris got past the screens and clogged up, but I'm still just guessing based on what we know.
Nothing to loose, if we can't get it clear I assumed we would have too look at a used ABS pump. Thought about looking for solenoids, but I figured they were unlikely to be available on their own. If you have one you're willing to part with, I'd be interested for sure, if we can't free this one up.
Thanks!
- Thread starter
- #59
Well we spent a good amount of time using brake cleaner and compressed air on the blocked solenoid, this afternoon. There is a chance we've made progress, BUT we can't get one of the o-rings back installed to then test if the solenoid is clear. This is one of the o-rings that seals the solenoid to the top housing.
Started noticing yesterday that all of a sudden the o-rings were difficult to reinstall. Hasn't been an issue up until now, but we've spent an hour or so and cannot get it in. I'm guessing they have swelled? Does anyone have a quick tip on shrinking o-rings? Heat or cold? Once again we are all ears.
Thanks in advance for your help! This seems to be one of those projects, where it's one thing after another. Fighting us a bit, but we will keep trying.
Started noticing yesterday that all of a sudden the o-rings were difficult to reinstall. Hasn't been an issue up until now, but we've spent an hour or so and cannot get it in. I'm guessing they have swelled? Does anyone have a quick tip on shrinking o-rings? Heat or cold? Once again we are all ears.
Thanks in advance for your help! This seems to be one of those projects, where it's one thing after another. Fighting us a bit, but we will keep trying.
- Sep 9, 2014
- 352
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for sure try ice water.