Piston Slap: The Self-Lathing CRX?

Sajeev Mehta
by Sajeev Mehta

Gareth writes:

Good afternoon Sajeev,

Read your latest and I’m determined to help you out. I recently had a bone-stock 87 CRX Si follow me home from an impound auction and, if I can get the damn thing through an Ontario Safety Inspection, I’ll let TTAC’s very own Derek K drive it.

Therein lies the rub, or brake rub really. The front discs were rubbing, a lot. Constant grinding sound as the wheels turn. I have since removed/lubricated the caliper sliders (they were a bit stuck from sitting) and measured the discs and pads using a measuring tape and straight edge, everything is above min specs.

With the pin lube the grinding noise has abated somewhat but continues, worst is passenger side.

The discs don’t feel warped (no front shudder under hard braking).

Your thoughts?

Sajeev answers:

OMG SON, why can’t someone find ME a nice CRX in Houston? What’s so wrong with giving the Piston Slap Guy a ride in your whip, huh? I care not of the distance between us, I can still feel the pain inflicted upon me! How could this happen to me? It must be my fault!

Perhaps less self-loathing and more self-lathing is in order.

Your situation reminds me of an old road test of mine, where the subject’s rear brakes rusted shut waiting for a test drive. Popping them free was fun, actually. That said, I don’t know what’s out-of-place on the CRX. My gut says that driving more will wipe off the rust/squeaks like a lathe in a machine shop. Assuming you’ve only driven it a few yards…sorry, meters for you Canadians.

So either replace the discs/pads/calipers now (and flush all the brake fluid) OR drive it slowly another 0.25 to 0.5 miles kilometers to learn more. This depends on the population density nearby and your faith in this machine. Driving the CRX it will either clear things up or the offending part will come forward as the brakes continue to lathe themselves.

Who knows, it could be a bad hub! But I bet you have rusty/sticky calipers, so flush the brake fluid and put fresh pads/calipers/new or turned rotors on too.

Cheap insurance, totally worth it. Don’t mess with rusty brake systems, DK will appreciate it.

[Image: Honda]

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

Sajeev Mehta
Sajeev Mehta

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  • Beerboy12 Beerboy12 on Aug 13, 2014

    So the pads should have some retaining clips and springs holding them in place, check those to. They keep the pad in place and allow it to move away from the disk because the pad, when not pressed against the disk, literally floats, but, the wheel has to be moving. I to think wheel bearings could be worn out, possibly due to the dragging brake/s. Sajeev's advice is sound though, replace the entire assembly (pads, disks and caliper) + bleeding for peace of mind. I would advise genuine Honda parts or good quality generics from a reputable brand.

  • 1000songs 1000songs on Aug 14, 2014

    Seriously - nobody has asked the obvious here. HOW MUCH?! Great find. Great rims. Great advice.

  • James Hendricks The depreciation on the Turbo S is going to be epic!
  • VoGhost Key phrase: "The EV market has grown." Yup, EV sales are up yet again, contrary to what nearly every article on the topic has been claiming. It's almost as if the press gets 30% of ad revenues from oil companies and legacy ICE OEMs.
  • Leonard Ostrander Daniel J, you are making the assertion. It's up to you to produce the evidence.
  • VoGhost I remember all those years when the brilliant TTAC commenters told me over and over how easy it was for legacy automakers to switch to making EVs, and that Tesla was due to be crushed by them in just a few months.
  • D "smaller vehicles" - sorry, that's way too much common sense! Americans won't go along because clever marketing convinced us our egos need big@ss trucks, which give auto manufacturers the profit margin they want, and everybody feels vulnerable now unless they too have a huge vehicle. Lower speed limits could help, but no politician wants to push that losing policy. We'll just go on building more lanes and driving faster and faster behind our vehicle's tinted privacy glass. Visions of Slim Pickens riding a big black jacked up truck out of a B-52.