Your InSinkErator has been working for decades.
It came with the house about 25 years ago.
It is an Essential model at 3/4 HP.
A plumber says the unit is still in good shape.
But you have a small crack and a steady drip.
The crack is at the “anti-vibration tailpipe” area.
You do not want a $600 replacement.
You want the small part that stops the leak.
Quick Q&A
Q: What part usually cracks on “anti-vibration tailpipe” setups?
A: It is often the rubber flex coupler at the discharge, not the disposer body.
First, confirm where the water starts
Dry everything under the sink.
Unplug the disposer or switch off the breaker.
Put paper towels under the discharge area.
Run cold water into the sink for one minute.
Do not turn on the disposer yet.
Then run the disposer for five seconds.
Look for the first wet spot.
That spot tells you what part to buy.
The most common “$5 part” you need
Many InSinkErator units use a flexible discharge coupler.
It is also called an anti-vibration tailpipe mount.
The current OEM part is often listed as InSinkErator 75499.
It may replace an older number, 74085, in some listings.
This part sits between the disposer outlet and the tailpipe.
It can crack with age and vibration.
What if the tailpipe is the cracked part?
Sometimes the discharge tube is split instead.
That tube may be listed as a separate part.
Match your tube shape before you order.
Look for a straight tube or a 90-degree tube.
Also, match the tube length.
Simple install tips
- Unplug the disposer and clear the cabinet.
- Loosen the clamp and remove the old coupler.
- Clean the disposer outlet and tube end.
- Slide the new coupler on fully.
- Reinstall the clamp and tighten evenly.
- Test with water and a short disposer run.
When to replace the whole unit instead
If the leak comes from the housing seam, replace it.
If the motor hums and trips, replace it.
If the unit smells burned, replace it.
But a discharge drip is usually an easy win.
Helpful links
- InSinkErator: disposal leaking at the discharge
- InSinkErator: replacement guide and discontinued models
- OEM part listing: InSinkErator 75499 flex coupler
- Parts counter listing: InSinkErator 75499
One last tip.
Find the model label on the disposer body.
Write down the model and serial number.
Parts can look similar, but fit can vary.
A photo helps at any parts counter.
I’m Chris Mayer, writing for Plumbing 101.