Hitachi NR83a Leaking Oil

[Keats26]

Hey y'all -

Having a minor issue with my faithful NR83a and hoping someone might be able to help. Been framing a roof and on Friday I noticed that it's leaking a small amount of oil out of the exhaust cover. Not a ton but enough that the hex bolts holding the exhaust cover on are wet.

Most troubleshooting info online has to do with air leaks but I'm trying to figure out what parts I might need to stop an oil leak. Definitely seems like the large gasket under the exhaust cover should be replaced but I'm not sure what else. Hoping to not have to go through and replace every o-ring in the nailer.

Let me know if you've had a similar issue and were able to fix it.

Thanks!

 

[Ole Slewfoot]

I recently rebuilt mine after 20? Years. $20 kit with urethane bumper, then i had to go back and order 1 or 2 little parts. No biggie its fast once you been in there before.

Tldr: just order the kit everyone sells.

 

[The Cobbler]

the only oil in those guns are what the user puts in to them . or your compressor had bad oil rings. there's not an oil reservoir in them .

 

[Keats26]

the only oil in those guns are what the user puts in to them . or your compressor had bad oil rings. there's not an oil reservoir in them .

Yeah, I know

 

[The Cobbler]

Yeah, I know

so what are you asking for then? oil that goes in is meant to come out ( thru the exhaust) . it's a perfectly normal situation when (too much) oil has been put in. no repair part will change that .

 

[Keats26]

I recently rebuilt mine after 20? Years. $20 kit with urethane bumper, then i had to go back and order 1 or 2 little parts. No biggie its fast once you been in there before.

Tldr: just order the kit everyone sells.

Right on thank you so much! I ordered some new gaskets already but I'll grab that kit.

Hope I can get another 20 years out of mine, was a hand me down from the guy who taught me how to frame.

so what are you asking for then? oil that goes in is meant to come out ( thru the exhaust) . it's a perfectly normal situation when (too much) oil has been put in. no repair part will change that

so what are you asking for then? oil that goes in is meant to come out ( thru the exhaust) . it's a perfectly normal situation when (too much) oil has been put in. no repair part will change that .

I was asking for trouble shooting/ repair parts advice because the exhaust cover shouldn't be slick with oil after normal use. And after normal (1-3 drops) oiling prior to use

 

[liliysdad]

Right on thank you so much! I ordered some new gaskets already but I'll grab that kit.

Hope I can get another 20 years out of mine, was a hand me down from the guy who taught me how to frame.



I was asking for trouble shooting/ repair parts advice because the exhaust cover shouldn't be slick with oil after normal use. And after normal (1-3 drops) oiling prior to use

It’s not making oil. The only oil that comes out is what you put in.

 

[The Cobbler]

good luck with your repair . I will say no more

 

[Keats26]

It’s not making oil. The only oil that comes out is what you put in.

I know it's not making oil and I've never said I thought it was.

I'm genuinely confused why my question is reading as so dumb. Gun oil isn't supposed to be leaking from around the exhaust cover when the gun is oiled correctly. That strikes me that some gasket/seal/whathaveyou isn't working properly, hence my asking if anyone has had a similar issue and knows which parts to replace.

 

[The Cobbler]

I'm genuinely confused why my question is reading as so dumb. Gun oil isn't supposed to be leaking from around the exhaust cover when the gun is oiled correctly.

okay. so I know I said I won't reply again. but, the tool is not meant to hold the oil you put in to it. it is carried thru the air to lubricate the moving parts in the path of the air. when it works it's way thru the gun it exits the exhaust with the air . it has no where else to go . .that's why they will say to oil tool daily or weekly or whatever .
no parts that you toss at the gun will make it do anything different.
I read another post of your where you say you're not mechanically inclined. That's nothing to be ashamed about , & Kudos to you for trying to learn how to repair stuff. but you are not understanding (or accepting) the concept of how these tools oiling system works .
I hope you make sense of this post. I am not demeaning you by any means .please don't take it as such

 

[Keats26]

Oh man... you should've seen me smack my forehead after reading your comment. Duh.

Thank you very much for explaining the (very simple) mechanism that was eluding me for some reason. Trying to get comfortable working on my nailers since they're one of the few tools daily I use that are easily repairable.

 

[AEAdam]

Yeah, this doesn’t sound normal to me. I think @The Cobbler may have been too dismissive.

A couple questions:
What pressure are you delivering to the gun?
Is it sinking nails?
Are you also getting oil from the trigger?
Does the gun ever smoke?

Air nailers are a little like internal combustion engines with a power stroke and a return/exhaust stroke and valves that open and close. If you are getting excessive oil on the exhaust side, it could mean the gun has too much oil and or some seal isn’t working or something is clogged. You should be seeing oil around the nose and the trigger.

see here https://www.everwinpneumatic.com/new/pneumatic-nail-gun-works

An o-ring kit sounds like a good idea to me. If it’s an older and well loved gun, I’d replace them all and clean everything really well.

 

[dscheidt]

Yeah, this doesn’t sound normal to me. I think @The Cobbler may have been too dismissive.
well.

It matches my experience when someone puts way too much oil into an air tool. Most of it comes out pretty fast, but it will weep oil for a long time. it doesn't take much oil to make the exhaust seem like an oily mess.

 

[Keats26]

It matches my experience when someone puts way too much oil into an air tool. Most of it comes out pretty fast, but it will weep oil for a long time. it doesn't take much oil to make the exhaust seem like an oily mess.

I dismissed the "too much oil" issue since I always use 2-3 drops but I realized that it's entirely possible that one of my coworkers could have used way too much sometime recently.

 

[Keats26]

Yeah, this doesn’t sound normal to me. I think @The Cobbler may have been too dismissive.

A couple questions:
What pressure are you delivering to the gun?
Is it sinking nails?
Are you also getting oil from the trigger?
Does the gun ever smoke?

Air nailers are a little like internal combustion engines with a power stroke and a return/exhaust stroke and valves that open and close. If you are getting excessive oil on the exhaust side, it could mean the gun has too much oil and or some seal isn’t working or something is clogged. You should be seeing oil around the nose and the trigger.

see here https://www.everwinpneumatic.com/new/pneumatic-nail-gun-works

An o-ring kit sounds like a good idea to me. If it’s an older and well loved gun, I’d replace them all and clean everything really well.

Hey thanks for the reply.

100-115 PSI depending on material and nail size
Sinking nails perfectly
A little oil from the trigger but not nearly as much
No smoke

I think you're right that an o-ring kit certainly couldn't hurt. A minor repair like that would be good practice for me as well.

 

[Ole Slewfoot]

That 1-3 drop figure assumes nailing all day... if 5 users all do it before a half hour session, the bonus will add up.
But extra oil will do far less harm than no oil, and an inspection every decade wont hurt anything either.