# Oil Leak In G0602 Lathe



## bluegrass-engineer (Aug 5, 2015)

Recently I bought a Grizzly G0602 lathe. I set it up and completed the required break-in without any troubles. As the owner's manual suggested I changed the oil immediately. Within a few hours there was a significant oil leak from the gear box. In a few days all the oil drained out. It was obvious that the leak was between the case and the front cover along the bottom edge. Page 84 of the manual shows an exploded diagram (boom!) of the gear box. It doesn't show a gasket of any kind.

I called Grizzly for technical assistance. Is there a gasket? Should there be a gasket? Do they have one cut to fit? It turns out that there is no gasket. Tech support could only guess at what was causing the leak, but they recommended removing the cover and using RTV to reseal it. By the way, the folks and Grizzly showed a great deal of concern and wanted to help. This post is not a criticism of Grizzly.

Removing the cover wasn't too difficult. All you have to do is remove four cap screws. The cover was painted on and stuck tight. After a couple of whacks with a rubber mallet, the cover fell on the floor, just missing my foot, and about a half cup of oil splashed onto my leg and the floor.

(Note to self: in the future hold onto the cover and put down a pan to catch the oil.)

After cleaning the floor and me I inspected the cover and the case. A bead of sealant had been put between the cover and the case. If you guessed that the sealant was thinnest along the bottom edge you would be correct. (It was thickest along the top edge. I guess gravity is different in China than here.) It could be that the way the sealant was put on may have contributed to the leak, but that's a guess.

Anyway, I put an adequate amount (I hope) of RTV around the edge of the cover and replaced everything. Oil will be put back after a 24 hour cure.

I took some pictures of the open gearbox and the back of the cover plate. The two gear trains are shown in different positions, C-III and B-II. The two large gears on either side split the shift forks on the back of the cover. When you operate the knobs on the front the forks engage the sides of those gears and move the respective gear train.


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## RJSakowski (Aug 5, 2015)

Thanks for the heads up.  I have not had a problem with oil leaks on mine.  I have had issues in the past with oil causing RTV to soften and swell when in contact with oil.  Permatex makes an oil resistant RTV which would be the choice sealant; Permatex 82180.  

Interesting how they chose to shift the gears.  I would expect to see wear issues and possibly gear box noise.

Bob


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## ch2co (Aug 5, 2015)

Interesting, I've never seen the inside of mine. Those shift levers are weird, no wonder you have to jiggle them and hunt around to engage them.
They look quite flimsy, but haven't given me any real troubles .But what do you expect for lower end machinery.  Mine is second hand and no leaks to speak of. Hope your RTV does the trick, I've used itwhen putting together automotive transmissions and after decades of use, nary a drop has crept out of them. 

Chuck the grumpy old guy


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## xman_charl (Aug 5, 2015)

*Its a cheap lathe, but serves me well.

Notice on mine, carriage lock is flimsy. Need
to make a beefier thingy.*

Threads okay.

Charl


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## RJSakowski (Aug 5, 2015)

xman_charl said:


> *Its a cheap lathe, but serves me well.
> 
> Notice on mine, carriage lock is flimsy. Need
> to make a beefier thingy.*
> ...


If by carriage lock, you are referring to the compound clamp, it is indeed flimsy.  It seems to be one of the first mods that people make.  I had made one for The G4000 9x19 some years ago and patterned the clamp for my G0602 after that. Here is the post that I did. http://www.hobby-machinist.com/threads/improved-g0602-compound-clamp.34796/

Bob


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## Fabrickator (Oct 9, 2015)

You guys jinxed me!  My G0602 is about 6 years old now and as of last week, I started noticing some minor mysterious oil around my drip plate.  I remember reading this post and sure enough it started leaking at the gearbox cover plate.  I picked up a tube of Permatex 82180 per RJ's suggestion. When I cleaned off the existing sealant I noticed some of the interior iron oxide paint on the sealing surface. I took a 400 grit sanding block to it to clean it up and make sure that it was machined properly (no flaws).  It looked good and so I just went ahead and resealed it.  

This was my 1st oil change (probably due anyway) after the initial break-in procedure oil change. When I drained the oil it was crystal clear and I didn't see any chips.  On the bottom inside, there was a very minor film of "CI mud" that didn't/couldn't drain out, but was safely out of harms way.  The gears look like new and the shifting mechanisms were solid.

Rick


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## Fabrickator (Oct 27, 2015)

I thought that I had this leak resolved until the other day when I noticed more oil under the lathe. I know that I got the gear box cover sealed well, but when I removed the cover I found the lens to have multiple cracks (crazing).  I think it happened after I put the cover on and sprayed it down with some electrical contact cleaner to clean up the residual oil during re-assembly.  Sometimes chemicals can attack certain plastics and paint, but electrical contact cleaner is not supposed to do this.

Anyway, rather than change the std. press-fit lens, I decided to thread it and buy a real one from McMaster Carr for the same amount.


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## billr (Jan 5, 2016)

Thanks for the heads up.
I just purchased the G0602 and I am learning all the details I can.
The first oil change after the break in was very clear.
If I have any complaints it is the ball oilers for the spindle bearings.
That could have been better designed, in my opinion.
Bill


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## Baithog (Jan 5, 2016)

I recently did my annual oil change and it was nowhere near clear. In fact, it was downright dirty (see photo). While you have the oil out of the lathe, you might want to upgrade the drain and fill plumbing. I installed a street ell and plug at the fill hole and a nipple and cap at the drain (see photo). The holes in the gear box are threaded 3/8" pipe. I may install a longer nipple the next time I change oil so that it clears the bench entirely. I had to buy a gallon of the oil, so I can do a lot of oil changes without running low.

*Corrected 1/4" to 3/8" - need more coffee!*


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## billr (Jan 5, 2016)

I did install the street elbow in the fill side; 3/8" on mine and the original plug fit perfectly.
I used a plastic ell.
There is not enough room for an ell in the drain since the gears are in the way but the nipple and cap should work.
I may also add a 90 deg. ell on the end of the nipple for easier draining.
Thanks for that tip.
Bill


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## ch2co (Jan 5, 2016)

Baithog said:


> I recently did my annual oil change and it was nowhere near clear. In fact, it was downright dirty (see photo). While you have the oil out of the lathe, you might want to upgrade the drain and fill plumbing. I installed a street ell and plug at the fill hole and a nipple and cap at the drain (see photo). The holes in the gear box are threaded 1/4" pipe. I may install a longer nipple the next time I change oil so that it clears the bench entirely. I had to buy a gallon of the oil, so I can do a lot of oil changes without running low.
> 
> 
> 
> ...



A couple of questions.  
One, how many times have you changed the oil since it was new?
Second, doesn't the street ell on the fill side of the box get in the way of the compound travel when you get really close to the gearbox?

CHuck the grumpy old guy


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## billr (Jan 5, 2016)

I have only changed the oil the one time just after the break in.
I have only had it since 12/28,
The street ell projects 1-5/16" toward the carriage.
I don't think it will be problem but I can pull the ell if needed.
Sure makes it easier to refill the gear box with a short funnel.
Bill


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## Fabrickator (Jan 5, 2016)

I didn't install a Fill Ell because it DOES interfere in the carriage travel.  I've had several projects that completely butted up to the gearbox.  Matter of fact, I had my DRO pickup on the gearbox side of the carriage and it limited travel so I moved it to the other side as well.

I use a custom made drain tray and a small funnel with a pliable filler hose attached, no problems.  I've changed my oil 4 times now and it's always been clear.  When I opened up the gearbox to change the level view window (earlier in this thread) I completely washed down and wiped up a very small amount of "metal mud" off the floor (considered pretty normal).


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## billr (Jan 5, 2016)

Ok Thanks.
Like I said if I find it a problem it is easy to remove.
Time will tell if I need to pull it.
I was guessing the depth below the drain plug was a reservoir to capture  any metal particles.
Bill


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## Baithog (Jan 5, 2016)

billr said:


> If I have any complaints it is the ball oilers for the spindle bearings.
> That could have been better designed, in my opinion.
> Bill



The balls fell out of the oiler in the headstock and one in the carriage. You can pull them with a pry bar after driving a sheet metal screw into the hole. A 5/16" ball oiler from McMaster-Carr fits. Order part #1214K3 Easy-Fill Oil-Hole Covers. The grizzly sourced part was back ordered with no target date.


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## billr (Jan 5, 2016)

I have the same problem with the ball oilers; one fell out in the headstock and the other in the carriage.
Thanks for the part numbers


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## ch2co (Jan 5, 2016)

When I got my used Grizzly lathe, it came with a lot of extras, one of which was a small bag full of these little ball oiler ports, and I soon found out why.
I like the cup oilers where they don't get in the way, but have just put up with these cheap *** little ball oilers where clearance is a problem.

CHuck the grumpy old guy


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## billr (Jan 5, 2016)

McMaster-Carr offers a wick type oiler, p/n #1221K15, but it fits a 1/4 " hole instead of 5/16".
Also expensive, but has 5/8 oz. reservoir.
They would be bulky on the headstock and probably won't work on the carriage.

Bill


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## Machspeed (May 21, 2022)

I know this is an old post but hoping to revive it, as it is relevant to my issues regarding this specific lathe. Hopefully the OP is still out there, but he's not posted since last year. Maybe someone can chime in? My lathe has leaked excessively since new. A few years back, I pulled the cover and attempted to seal but it continued to leak. I pulled the entire gearbox off a few days ago and re-sealed it and put it on my bench to see if it would leak and sure enough, it is still leaking but from the site glass. I like the OP's approach in addressing this. Wondering if there is a part number for the site glass he used??? Thanks!!!


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## RJSakowski (May 21, 2022)

I have had a 602 for seven years and have had absolutely no problems with a gear box leak.  

RTV sealant tens to soften and swell in petroleum products.  Permatex makes a special formulation RTV for use with gear oil.  I used it several years ago when I repaired my tractor transmission with no leaks.  Apply an even coat and allow to thoroughly set up.  A second thin fresh coat can be used if a bond is desired. https://www.permatex.com/products/g...kers/permatex-gear-oil-rtv-gasket-maker-3-oz/


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## WobblyHand (Oct 31, 2022)

My G0602/G0752Z has started to leak out the front seal of the gearbox.  It's not a fast leak, but it's a messy one.  It seems to drip on the edge of the drip pan so about 75% of the oil drips off the edge of the pan.  Do you need to pop out the roll pins to remove the knobs to get the printed sheet metal panel off?


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## RJSakowski (Oct 31, 2022)

WobblyHand said:


> My G0602/G0752Z has started to leak out the front seal of the gearbox.  It's not a fast leak, but it's a messy one.  It seems to drip on the edge of the drip pan so about 75% of the oil drips off the edge of the pan.  Do you need to pop out the roll pins to remove the knobs to get the printed sheet metal panel off?


The holes for the gear shift knobs in the sheet metal will clear the knobs.


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## WobblyHand (Nov 1, 2022)

RJSakowski said:


> The holes for the gear shift knobs in the sheet metal will clear the knobs.


And so they do.  I don't know why I didn't see that before!

I tried cleaning up the oil, it seems to be everywhere.  I do think one source of the leak is the sight glass.  If I touch the sight glass even lightly, I see oil moving at the seal boundary.  It is also slightly wet under the sight glass.  Also found oil inside the threaded hole of the gear box cover.  This is the hole on the bottom right.  It appears it is drilled nearly all the way through the cover.  All of the holes for the cover appear to have been drilled in place.  They are not straight in, they are all angled downwards.  The bottom right hole could be weeping through a casting imperfection that gets into the hole.  Or maybe, it is just the sight glass weep.  A replacement front gear box cover does not have pre-drilled holes.  The sight glass is cheap. 

Maybe I will pull the sight glass and check if it is an o-ring problem.  There is some OEM paint over spray on the site glass, they didn't do a good job of masking.  For that matter, they didn't do a good paint prep on a lot of the lathe.  I have areas of paint peeling off to the base metal.


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## WobblyHand (Nov 1, 2022)

I don't know if it is this simple, but I noticed the sight glass was sort of sticking out.  So I pushed it flush to the surface.  Have cleaned everything up.  In the process a lot of paint fell off.  The back side of the paint was oily.  It's been a few hours, but I don't see evidence of a leak.  The picture is before a lot of the paint fell off.  Yes, that's bare metal.


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## WobblyHand (Nov 2, 2022)

Knock on wood  no dripping.  Everything seems dry.  Reinstalled front panel.  It covers up the bare metal - but I know it is there.  Will need to paint sometime or another.  Can't see a reason to remove the front gear box cover, as it isn't leaking.

Does anyone know if there is spray paint in Grizzly "putty" color?  The only paint I have found on Grizzly is in a little can.  I don't have air in my basement shop, so spray paint is better for me.


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