ABS Modulator Leak

[G. Wiffington]

So I have noticed that I have a leak coming from around the ABS Modulator.
I first thought I was leaking PS Fluid from the speed sensor but, I drove around & did not see any change in the PS Fluid level. That was when I
noticed my ABS reservoir was a little low. I have filled the ABS up, so I will have to keep a close eye on the level.

I could not locate exactly where it was leaking from but there seems to be brake fluid
on the passenger side wheel well as if fluid is leaking from the left side of the modulator.
I cleaned up the dirt & gunk around the area so I can try to see where it is leaking from.
It does not look like it is leaking from the hard lines or the fittings though.

I am not too familiar with the ABS Modulator so, are there any well known
common leaking points that I can check?

Can I replace the whole Modulator from another CB or would that be a gamble?

I saw the DIY on the ABS delete but it I would like to fix the leak instead of ripping the whole ABS system out.

Any ideas would be great. Thanks.

[Rilas]

While I don't know of any places it is known to leak, I have a non-leaking ABS modulator laying on the garage floor I just took out of my '93.

[G. Wiffington]

While I don't know of any places it is known to leak, I have a non-leaking ABS modulator laying on the garage floor I just took out of my '93.

How much?

[G. Wiffington]

I kind of want to just do the whole ABS delete but the DIY doesn't have too
many pictures that I can follow. The instructions seem pretty straight forward
but, I just wish there were more pictures so I could feel more confident in
doing the procedure.

[masospaghetti]

I've had to replace modulators for a different reason (allowing fluid to transfer from the ABS reservoir to the master cylinder, or vise versa). I believe there are some o-rings that could cause an external leak. Maybe the seal for the plastic tank is bad? It's not hard to remove the tank to check.

It's definitely a gamble to get another used one since these parts are so old at this point.

[Losiracer2]

I deleted my ABS system in my 93 EX Coupe. Saved me about 25lbs of lines, computer, sensors and of course that modulator and Accumulator located on the front cross member.

My modulator was leaking too back in Nov 2011, looked like from the screw in front? Honda wanted $900+ for one so I opted to do the non-ABS conversion. My brake pedal feel is way better now with the ABS deleted then it was with the ABS system functioning. I can modulate the pedal a lot better now too, even up until the point of locking up, then I just let off and i regain control again.

You'll need:

-Integra 40/40 proportioning valve, get from one with a rear disc, it'll have 4040 stamped on it.
-Front hard lines to calipers from an LX/DX accord
-Different MC, I upgraded to a Prelude VTEC 1" MC which was only 30 bucks at Autozone (reman. Nissin which was held up since 2011 fine) Or you'll have to reflare one of the fittings on the LX/DX lines (which to me is more work and could be a failure point in the future since I don't know how to flare lines that well lol)

Probably cost a total of 20-30 bucks in the JY for the prop valve and 2 hard lines and 30 for the MC and another 10 for fluid so you could get this done for about 75-80 bucks realistically. Took me about 3 hrs to get everything removed and plumbed, new MC bench bled and installed and then another hour to bleed the brakes with a friend. Definitely invest in some thicker flare wrenches. Harbor freight makes a good less expensive set that broke even the most stubborn brake lines loose without rounding off the heads of the fittings.

The parts list is pretty simple, its just removing the ABS hard lines against the firewall was a pain (I ended up cutting them out with dykes since they snaked around everything), but removing the accumulator and modulator frees up a lot of space in the engine compartment and makes it look cleaner, not to mention the weight savings of those units off the front end.

Also, removing all the ABS sensors and lines from each of the suspension knuckles makes servicing brakes, wheel bearings, rotors, halfshafts, etc. a lot easier since those parts won't get in the way.

[G. Wiffington]

I've had to replace modulators for a different reason (allowing fluid to transfer from the ABS reservoir to the master cylinder, or vise versa). I believe there are some o-rings that could cause an external leak. Maybe the seal for the plastic tank is bad? It's not hard to remove the tank to check.

It's definitely a gamble to get another used one since these parts are so old at this point.

Yeah I kept seeing threads about people having an overflowing Modulator.
It sucks because I just cannot locate exactly
where it is leaking from because of how far in the back of the bay it is located. Mine loses the fluid somewhere else instead of overflowing through the cap.
I have checked the fittings to see if they were loose but all seems okay.
The best idea I have is that it looks like it is running down the passenger side of the bay, but not the firewall.
BUt, yeah you are right about it being a gamble. I feel like if I am going to go to the extent to pull the Modulator I might as well follow through with
the ABS delete all together.

[G. Wiffington]

I deleted my ABS system in my 93 EX Coupe. Saved me about 25lbs of lines, computer, sensors and of course that modulator and Accumulator located on the front cross member.

My modulator was leaking too back in Nov 2011, looked like from the screw in front? Honda wanted $900+ for one so I opted to do the non-ABS conversion. My brake pedal feel is way better now with the ABS deleted then it was with the ABS system functioning. I can modulate the pedal a lot better now too, even up until the point of locking up, then I just let off and i regain control again.

You'll need:

-Integra 40/40 proportioning valve, get from one with a rear disc, it'll have 4040 stamped on it.
-Front hard lines to calipers from an LX/DX accord
-Different MC, I upgraded to a Prelude VTEC 1" MC which was only 30 bucks at Autozone (reman. Nissin which was held up since 2011 fine) Or you'll have to reflare one of the fittings on the LX/DX lines (which to me is more work and could be a failure point in the future since I don't know how to flare lines that well lol)

Probably cost a total of 20-30 bucks in the JY for the prop valve and 2 hard lines and 30 for the MC and another 10 for fluid so you could get this done for about 75-80 bucks realistically. Took me about 3 hrs to get everything removed and plumbed, new MC bench bled and installed and then another hour to bleed the brakes with a friend. Definitely invest in some thicker flare wrenches. Harbor freight makes a good less expensive set that broke even the most stubborn brake lines loose without rounding off the heads of the fittings.

The parts list is pretty simple, its just removing the ABS hard lines against the firewall was a pain (I ended up cutting them out with dykes since they snaked around everything), but removing the accumulator and modulator frees up a lot of space in the engine compartment and makes it look cleaner, not to mention the weight savings of those units off the front end.

Also, removing all the ABS sensors and lines from each of the suspension knuckles makes servicing brakes, wheel bearings, rotors, halfshafts, etc. a lot easier since those parts won't get in the way.

See this response is what I need to build my confidence up to actually do
the delete haha. My fear was not being able to remove the fittings without rounding off the heads as well as actually ripping out the old lines which seems pretty intimidating. I was telling Rilas that I was on the verge of rounding off the fittings when replacing my Clutch Master.

BUT, honestly referring back to what you said about cutting the lines with dykes, do I honestly need to worry about even disconnecting any of the lines from the Modulator (regarding rounding off the fittings)? I mean if I am cutting the lines it really doesn't matter because I will not be reusing them, correct? I would assume that the two fittings I need to be concerned with would be the two rear lines that connect to the "H" shaped piece that is routed to the MC, correct?

Another note is that the engine is still in the bay. Is it that much of a pain
to perform the delete with the engine still in the bay?

[masospaghetti]

Honestly, I've had better luck with a small, high quality adjustable wrench (where it fits) even compared to a flare wrench, has less of a tendency of rounding off stuck fittings. Flare wrenches are an obvious improvement over box wrenches though.

For the fittings that are really stuck solid and/or rounded off, use vise grips. I've never had a fitting that I couldn't get off with vise grips. Obviously this chews up the fitting so try using an adjustable or flare wrench first.

[Losiracer2]

See this response is what I need to build my confidence up to actually do
the delete haha. My fear was not being able to remove the fittings without rounding off the heads as well as actually ripping out the old lines which seems pretty intimidating. I was telling Rilas that I was on the verge of rounding off the fittings when replacing my Clutch Master.

BUT, honestly referring back to what you said about cutting the lines with dykes, do I honestly need to worry about even disconnecting any of the lines from the Modulator (regarding rounding off the fittings)? I mean if I am cutting the lines it really doesn't matter because I will not be reusing them, correct? I would assume that the two fittings I need to be concerned with would be the two rear lines that connect to the "H" shaped piece that is routed to the MC, correct?

Another note is that the engine is still in the bay. Is it that much of a pain
to perform the delete with the engine still in the bay?

No, as long as you have those wrenches I mentioned, they'll make it a lot easier. They're literally twice the thickness of a normal boxend wrench and will not flex against stubborn brake lines.

As long as you mark off which lines are going to the rear calipers, and don't touch those, the rest of the hardlines you can snip at your leasure. I didn't even bother removing the fittings going into the modulator or accumulator, I just cut enough to get them out of the locations they were at.

But I reviewed my notes, and in order to use the factory LX/DX lines, you will have to reflare the rear line going into the MC, regardless if you reuse yours or use a prelude 1" MC. Since they're both used for ABS equipped cars, the MCs from the factory had a slightly larger fitting on the rear. Or you could use a LX/DX MC but to me that would be a downgrade since its a 7/8" bore vs. the current 15/16" of the EX. Autozone sells a reflare tool (4 bucks) that wasn't that difficult to use as well as replacement fittings for 3 bucks.

It's also fine to get a used 4040 prop valve, just try to get one from a car yourself so you can see if its bone dry. If it is, then you should have no issues with it leaking. But if its wet around any of the lines going into it, then stay away from those. I think they're upwards of 100+ at a dealer new and only about 10 bucks at a JY.

I did everything on a running and driving car, I think I even left my intake manifold on there as well. I would start with removing the bulkly modulator and accumulator, and those associated lines, then it'll simplify the process a bit and will help you reduce the amount of lines little by little, until you're left with just the rears you need to keep for the rear discs. Then I would remove the MC, to give easier access to the Prop. valve directly below it about a foot. Then install the new 4040 prop valve in place of the distribution block and work your way up by installing the LX/DX lines on that and route those to each of the corresponding front wheel corners.

Here's some pics of all the stuff I threw away, totaled 25lbs


^^^All the ABS Junk weighing in at 25 lbs

[Granite CB7]

On my old 93 EX, I did the ABS removal while the IM was off the engine. This made it alot easier but it's still hard since I'm kneeling on the valve cover and reaching down towards the rear crossmember, but it's all worth it in the end. I've heard of some people doing the removal with the engine as-is, so it's def possible. If you have some IM upgrades planned maybe do it at the same time. I highly recommend a 10mm flare nut wrench, it will not fail you. Also prev mentioned, but now is a great time to upgrade to a 4040 prop valve too. I highly suggest keeping the original MC but if you do go down to a DX/LX MC you must also change the booster too, do not mix and match NON-ABS MC with ABS booster. Reflaring the M12 fitting on the DX/LX line really isn't that bad. I did end up cutting the old ABS lines, it was the best part of the project! Not required, but I bled the pressure out of the system by unscrewing the bleeders @ the ABS components and putting a rag over the bleeder, you'll be shocked how pressurized it is. On my new 91 SE, I did the ABS removal with the engine and tranny out of the car and it was wayyyy more fun, obviously! Good luck!

[G. Wiffington]

Honestly, I've had better luck with a small, high quality adjustable wrench (where it fits) even compared to a flare wrench, has less of a tendency of rounding off stuck fittings. Flare wrenches are an obvious improvement over box wrenches though.

For the fittings that are really stuck solid and/or rounded off, use vise grips. I've never had a fitting that I couldn't get off with vise grips. Obviously this chews up the fitting so try using an adjustable or flare wrench first.

Yeah, Vice Grips seem to always save the day haha. I have some flare wrenches but they are pretty thin so I should look into some more heavy duty ones that actually grasp the whole width of the fitting.

[G. Wiffington]

No, as long as you have those wrenches I mentioned, they'll make it a lot easier. They're literally twice the thickness of a normal boxend wrench and will not flex against stubborn brake lines.

As long as you mark off which lines are going to the rear calipers, and don't touch those, the rest of the hardlines you can snip at your leasure. I didn't even bother removing the fittings going into the modulator or accumulator, I just cut enough to get them out of the locations they were at.

But I reviewed my notes, and in order to use the factory LX/DX lines, you will have to reflare the rear line going into the MC, regardless if you reuse yours or use a prelude 1" MC. Since they're both used for ABS equipped cars, the MCs from the factory had a slightly larger fitting on the rear. Or you could use a LX/DX MC but to me that would be a downgrade since its a 7/8" bore vs. the current 15/16" of the EX. Autozone sells a reflare tool (4 bucks) that wasn't that difficult to use as well as replacement fittings for 3 bucks.

It's also fine to get a used 4040 prop valve, just try to get one from a car yourself so you can see if its bone dry. If it is, then you should have no issues with it leaking. But if its wet around any of the lines going into it, then stay away from those. I think they're upwards of 100+ at a dealer new and only about 10 bucks at a JY.

I did everything on a running and driving car, I think I even left my intake manifold on there as well. I would start with removing the bulkly modulator and accumulator, and those associated lines, then it'll simplify the process a bit and will help you reduce the amount of lines little by little, until you're left with just the rears you need to keep for the rear discs. Then I would remove the MC, to give easier access to the Prop. valve directly below it about a foot. Then install the new 4040 prop valve in place of the distribution block and work your way up by installing the LX/DX lines on that and route those to each of the corresponding front wheel corners.

Here's some pics of all the stuff I threw away, totaled 25lbs


^^^All the ABS Junk weighing in at 25 lbs

-You are the man!
- Referring to the MC bore, I went to Rockauto & found a Dorman MC Non-ABS with the Bore : 15/16". Part : DORMAN M39882 Will this be the match I am looking for? The info states that both outlets are a M10x1.0. My MC on the car now has been leaking for sometime anyway.
-Good info. on the 4040 valve. I keep seeing threads on Honda-Tech about some 4040 valves leaking..is this a very common thing?
-All the steps you said for the procedure is exactly how I was thinking, so I am on the right track.
-Wow I didn't realize how heavy the ABS system was. My bay will look so much cleaner after the delete.

Thanks for the detailed responses. I appreciate when members on the forum really put thought into helping out when needed!

[G. Wiffington]

On my old 93 EX, I did the ABS removal while the IM was off the engine. This made it alot easier but it's still hard since I'm kneeling on the valve cover and reaching down towards the rear crossmember, but it's all worth it in the end. I've heard of some people doing the removal with the engine as-is, so it's def possible. If you have some IM upgrades planned maybe do it at the same time. I highly recommend a 10mm flare nut wrench, it will not fail you. Also prev mentioned, but now is a great time to upgrade to a 4040 prop valve too. I highly suggest keeping the original MC but if you do go down to a DX/LX MC you must also change the booster too, do not mix and match NON-ABS MC with ABS booster. Reflaring the M12 fitting on the DX/LX line really isn't that bad. I did end up cutting the old ABS lines, it was the best part of the project! Not required, but I bled the pressure out of the system by unscrewing the bleeders @ the ABS components and putting a rag over the bleeder, you'll be shocked how pressurized it is. On my new 91 SE, I did the ABS removal with the engine and tranny out of the car and it was wayyyy more fun, obviously! Good luck!

-I am trying to go the route of relying on my long ass arms instead of pulling the IM. Trying to use my 6'4" height to my advantage this time haha.
-Yeah I have some flare wrenches but they are so baby! They were a cheap set that I bought from Advanced Auto forever ago. I need a nice THICK set that grasps the fitting even more.
**Regarding the Booster...can you elaborate on why you cannot use an ABS BB with a Non-ABS MC? Is it because of the rod length differs between ABS & non?
-Haha I am excited to cut those damn ABS lines. It looks like shit all those lines.

[G. Wiffington]

Well I guess I answered my own question because I found this thread:

http://www.cb7tuner.com/vbb/showthread.php?p=3245204

Looks like there is a pretty good distance in length of the rod when comparing the ABS BB to the Non-ABS BB.

Does anybody know if the bore size varies for the Non-ABS BB? When I was looking up BB on RockAuto they don't list bore size, only listing if it for an ABS or a Non-ABS setup.
Losiracer2 said that the LX/DX MC has a 7/8" bore but I also found a MC listed for the LX/DX with a 15/16" bore. : RAYBESTOS MC39882 {#2539882} Professional Grade; New; Bore Size=15/16"
DX Model; LX Model
Would that MC with the 15/16" bore work with the Non-ABS BB? Sorry, I just am not sure on the details about the bore size. I just noticed the BB were not listed with any specifications regarding bore.