rear drums to disk - 95 civic dx hatch

As the subject says, I have a 1995 Civic DX hatchback. The previos
owner of the car, my roomate, had the rear drums converted to disk
breaks. I remember at some point after they were converted, I helped
him change the pad on the back, but the new pads caused the brakes to
seem like they were dragging all the time, you could even smell the
brake dust after just driving it down the street from the house, so we
just put the old pads back on never messed with them again. Well now
the car is mine and the break situation has always bothered me. I have
not noticed any problems with breaking, but I still want to rectify the
situation. Now since it had drums then the factory proportioning valve
on the car would be set to always have few pounds of pressure on the
rears at all times since shoes always need pressure to hold them next
to the drums. I'm not sure if the valve was replaced, and I know the
one that is in the car now is not an adjustable one. Is there another
honda of the same erra I can go to a junk yard and get it's
proportioning valve that was desinged for 4 wheel disk and put it on
and work fine, or what other options are there.

 

the correct proportioning valve is absolutely vital. especially for
safe braking in the wet.

for integras with the 10.25" front disks & rear disks, the proportioning
valve has "4040" stamped on it. for ordinary civic dx's with 9.5" front
disks & rear drums, it's "3525" iirc. i think you want something like
"3540", but check the size of your fronts. if you can get one from the
95 si, you should be ok. if you get the correct valve, lease post the #
to group for reference.

i think civics, preludes, crx's, integras, 88 through 95 had the same
proportioning valve style, only valved different per the number stamped
on the side.

 

While it is true, as jim beam pointed out, that you need a proportioning
valve designed for rear discs, the above statement sounds an awful lot like
an urban myth. The shoes in a rear drum system are held away from the
friction surface by the upper and lower return springs. It's the brake
adjuster, not the proportioning valve, that's used to keep the shoes close
to the drum.

Eric

 

Well, I appretiate both of your replies, but I am still not sure what I
should do then. I suppose I just need to take some time and put new
pads in the back and see if they still stick, if they do, then what? I
know the front disks are the factory, whatever size that is. I think
the back disks were from a ~95 integ's rear. I'm still thinking the
valve was the prob. Chances are the the rear disks that came from an
integra were the same as what got put onto the civic si, so I'll
probably need to find a valve from a 95 civic si or a 95 integra.

 

I thought that jim's post was pretty clear. In it, he wrote that "the
correct proportioning valve is absolutely vital."

 

ok, sorry i guess i was being stupid . I'll do some looking for the
correct valve. Thanks again.

 

Did your friend have them turned before he put the rotors on? They could be
warped a little and dragging.

 

Eric in reply to your email you sent me:

You are correct about the rear pistons needing to be turned to retract
into the housing. We figured that out when we had put new pads in the
rear, the caliper slipped back down over the rotor just fine with new
pads, but then when all was said and done and reassembled and you press
the brake peddle in a few time to push the piston back out, that's when
they stick. Your thought on corrosion could be the problem, I suppose
I could take a day and disassemble it all and see. I have done some
searching for the correct proportioning valve and am only able to find
an OE one at my Honda dealer, but that it is $170, bit steep for me
right now. Went to a junk yard but no luck there either. Tried
searching all over online and can't find squat. So I'll probable just
have to keep looking and hope I get lucky and/or hope I can muster up
the money for the OE one.

Any other thought you have on this would be appreciated.

 

A proportioning valve from http://www.hondaautomotiveparts.com for a '95
Civic Si is $130. You can access an online version of the factory service
manual at http://www.honda.co.uk/owner/CivicManual/index.html. You don't
need to fully disassemble the caliper to check for signs of corrosion on the
piston. Often times you can just carefully pull the dust boot away from the
piston using blunt needle nose pliers and inspect the outer piston surface
with a flash light. If you see corrosion on the outer part just under the
boot, then there's likely more further inside. Be careful when you pull the
boot back to make sure that you don't damage it. Note that rebuilding the
rear calipers is an involved process, check out
http://www.honda.co.uk/owner/CivicManual/pdf/19-25.pdf for disassembly and
http://www.honda.co.uk/owner/CivicManual/pdf/19-28.pdf for reassembly. Most
shops use remanufactured units rather than rebuild them in-house.

By the way, I don't recall if you've mentioned how much rear brake pad is
remaining. The minimum thickness is 1.6 mm so if you have plenty of pad
remaining, and rear disc pads usually wear slowly, you may not need to worry
about replacing the pads for a little while.

Eric

 

I just bought one on ebay for $25 plus shipping. (used)

 

By the way, when you installed the new pads did you correctly align the pin
on the pad's backing plate with the cutout on the piston? For reference see
http://www.honda.co.uk/owner/CivicManual/pdf/19-21-1.pdf.

Eric

 

I'm not sure how much pad is left, I'll have to look. As for when the
pads were installed, since my roomate owned the car at the time, I
didn't take to much interest other than answering questions he had when
he put them on (first time he ever did it) and just kind of watching
casually. Now I have changes pads (front and rear) on every other car
I've owned so I'd hope that I would have noticed if they were aligned
wrong or not, but no one is perfect, especially me.

 

I just looked at the pads and there is probably a good 4 to 5mm of pad
on each side. Just so you understand it's not that I want to change
the pads persay, it's just that the system is not right and was not
installed correctly and that is why i'm wanting to fix it. I'm one of
those people who can't stand things like a little string hanging off of
clothes or to have a one light burnt out in a two buld fixture. I have
this need to fix it and make it correct.

 

It sounds like the thing to do is get the correct proportioning valve and
see how they work after that.

Eric

 

I figured that would ultimatly be what I would need to do. I have to
say though you have given me a few great sites to find info for future
reference. Those links to the service manual are great. All I have is
a Haynes manual and it gets me through all right, but the online manual
could come in very handy later. Thank you.

 

to ensure you have the correct proportioning valve, measure the front
disk diameter and select accordingly.

 

forgot to say, go the junk yard and check out the older preludes -
should have the correct valve if you have the smaller front disk setup.
check per my previous post for the right version numbers depending on
what you have.