Oil Leak In G0602 Lathe

[bluegrass-engineer]

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.

 

[RJSakowski]

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

 

[ch2co]

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

 

[xman_charl]

Its a cheap lathe, but serves me well.

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

Threads okay.

Charl

 

[RJSakowski]

Its a cheap lathe, but serves me well.

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

Threads okay.

Charl

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

 

[Fabrickator]

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

 

[Fabrickator]

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.

 

[billr]

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

 

[Baithog]

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!

 

[billr]

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