xSTUDDSx

I have a question about a grinding noise that I am getting that is extremely annoying and probably not very good for the car.

About a month ago, I bought this 1987 Honda Civic Si Hatchback for a good daily driver that got awesome gas mileage. It was in rough condition when I bought it and now I'm trying to clean it back up to great running order. When I first bought it, It had a problem with the clutch. It would slip when changing gears and it also made this weird grinding noise after your let off the gas and weren't on any pedals but were still in gear. If you shift to neutral and coast you don't get the sound, only when your in gear and let off the gas.

So anyway, I thought I just needed a clutch so I got online and ordered a clutch kit and installed it. Well after installing it, the slipping went away immediately and it shifts great, but that grinding noise is still there. And its loud. You can hear it from outside the car when it does it its so loud.

My question is, what is causing that noise? Its really annoying and I'd love to get it fixed because I'm sure its not good on whatever parts are grinding together. And just to reiterate, when your on the gas, on the break, shifting, or in neutral you don't here the sound, its only when your in a gear and let off the gas and the car begins to automatically decelerate due to the gears.

As for everything else I've done to the car I've: replaced plugs, drained oil, replaced oil filter, replaced oil, flushed radiator, replaced the coolant, power washed the motor, powerwashed the transmission, replaced tranny fluid, and as I stated above I replaced the clutch kit.

If you guys have any idea what is causing the problem and how to fix it I'd greatly appreciate it. Thanks in advance!!

cbstd

Best case scenario- it's only the throw out bearing.
Worst case scenario- it's the transmission.

Make sure you have enough MTF fluid in the tranny, most people ignore that viatal fluid. If you change your MTF, *maybe* the grinding goes away. If not, start looking for a new tranny.

xSTUDDSx

Well the throwout bearing came with the clutch kit so it has already been replaced. So I guess I'm looking at the transmission. How much is it gonna run me to replace that?

Lifex

i saw one for sale on red pepper racing forums . . .but it's WAY down the list should be no more than 500 if you find a good runner with low miles . . .that one FS is a 5spd gw tranny which I am assuming you have since you have the 1.5L Si CRX

cbstd

Have you tried replacing the MTF first? Two quarts of 30w will work.

johnjw

most likely the imput shaft bearing on the trans. If you remove the trans and feel the imput shaft it will most likely have some play. I would find somebody or school yourself and tear the trans apart and replace it. I had 3 of those trans do the exact same thing you describe.