DeWalt D55146 leaks air around Regulator knob

Published Categorized as Air Compressor Leaking Air, Air Compressor Troubleshooting, Air Pressure Regulator Guides, Dewalt 11 Comments on DeWalt D55146 leaks air around Regulator knob

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What’s the fix for DeWalt D55146 that leaks air around Regulator knob

by John Harrell
(Orange, Texas)

I have a DeWalt D55146 that leaks air around the regulator knob. Is there an easy fix for this problem ?


It’s Not the diaphragm!

by: Anonymous

This model has a flaw, the nut that the shaft turns in strips out, then it leaks. Cannot find just the nut, need the whole stupid “rebuild kit” that is generic for a variety of models, at least 20 bucks!
-Tom in PA

D55146 regulator repair kit
D55146 regulator repair kit – available from online retailers


55146 leaks air around Regulator

by: Doug in

You should pull the cover and make sure it’s the regulator that’s doing the leaking…

If it’s the reg, a $21 repair kit is available.

But if it’s the manifold, you’re looking at $130 for a new one.

If it’s the manifold, I’d suggest you build a new one from pipe fittings – it’ll probably be cheaper and more maintainable in the future. Looks be damned.


DeWalt D55146 that leaks air

by: Bill

For most folks the complications of trying to find parts for a specific brand regulator, and their unfamiliarity with disassembling and reassembling a regulator, along with the fact that many small air compressors use a regulator you can buy new for $15, suggests that the best course for many is to just replace the regulator with a new one.

If air is leaking around the regulator knob, that suggests that the diaphragm inside is cracked. You can just replace that if you care to undertake the process described above.

Do you have a DeWalt D55146 that leaks around the regulator knob? Care to add a comment? Please do.

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I Bought a regulator valve repair kit and completed it with ease. Still leaking from hole in knob (relieving valve?) I checked process and still leaking.
Also… is the diaphragm the disc that comes in the repair kit? Or is there something I’m missing…

My company has purchased literally hundreds of the 55146’s. Have had great results until 2019. Regulator leaks on 1 out 4 purchased.

Is that a DOA, or an early fail?

We have a Dewalt D55146 that leaks around the regulator knob again. We replaced the regulator in June 2019 it was leaking just like the current one. Is this a common problem with Dewalt?

If you have a type 1 (original) probably, as parts don’t appear to be available.
If it’s a type 2, it is a wear part, and probably should have lasted longer, if you followed the instructions.
Do you adjust the regulator frequently?

How do I tell if it is a type 1 or type 2?

It is on the same sticker with the model number – usually upper right corner.
If that’s missing or illegible, try searching “D55146 parts”
Depending on the like you take, you’ll be asked for the type or given a choice. There are four different “type”s, 1 to 4. Find the one(s) that look like yours. Some parts are the same, some different.

Have fun and good luck.

Label is pretty much gone except for the model. I got lucky there. It was a bad o-ring. The smallest one in the regulator. I have a big box of assorted o-rings and found one to fit. Cleaned up the rest of the components and greased everything and all is good now. Holds pressure like a new compressor.
Thanks for the assistance.

Cool. Those o-ring sets can be nice to have around.
Thanks for letting us know you found a fix.

I took the cap off the bottom of the regulator and noticed that the spring was all the way compressed and the little piston was stuck in the brass sleeve( not moving) , so I pulled harder on the piston until it came out, then cleaned and lubed it and put it back in and it was freely moving up and down now ( against the spring pressure) . That worked for my leak around the regulator knob. It wasn’t the diaphragm ( although I did disassemble it and clean and lube it anyway while I had it apart)

Atm –
That’s good to know – any idea how/why it was stuck?