Porter Cable G8 maintenance, lubrication, owners manual, etc...

Hello again. I've been gone for quite some time due to family and medical issues, but finally getting back to some long postponed projects. My current target is my Porter Cable G8.

I acquired it some years ago in functional condition but needing some attention. It's got a bunch of minor issues like broken hinge and missing latches on belt door (which has a major belt bite from tracking out), broken sheave on motor pulley, etc. But everything mechanical worked/works great, but I never really put it to use, and when life got in the way, I set it aside for "some day". It appears that day has come.

So, the main thing I need is an owners manual. If I could put my hands on one of those (ideally download), my other questions become moot. It's an early model, with all the swoopy curves and art deco look, I suspect from the 40s or early 50s. I found a brochure online for a late 50s (I think?), and it had a different more square base with the same main casting. But I suspect any manual will do.

Next, what lube is used for the main hubs? The upper idler has a high pressure fitting like used for grease on cars. However, I know that these are also sometimes used for high pressure oilers, for example, on the old bridgeport turret mill ways. The lower hub has what appears to be an access port like you find on lots of automobile axis. It has a flat-head screwdriver slot. Yes, I'm going to pull them and see what I can fish out, but even after grease/oil question may be resolved, the next is "what grade/type". So, thought I would ask along with the manual ask.

Second, has anyone ever taken the top side of one of these apart? The massive tracking and tensioning system (looks a bit like a shaper tool slide) doesn't appear to have a "this is how this comes off" feature. But I'm wondering if removing the pivot bolt for the tracking rocker will let the whole upper hub come out the opposite side complete with wheel. The wheel hub also have a cover plate with screws, and I suspect I'll find a spindle nut under there. Also allows investigation of lube, but really, it runs so freely and smooth, I'm a bit loath to add to my "need to do" list. The main thing I'm after is removing that tensioner slide to clean and lubricate it along with the screw, right now they are the only thing on the grinder that doesn't work smoothly and easily. I'll probably never use it enough to damage it as it is now, but it's something I would like ot address. I can start taking apart and figure it out as I go, but since I'm posting for a manual, I thought I might include this point as well.

And finally, mine doesn't have the wet grinding coolant system. I normally avoid the mess of coolant, but this seems like an exception. As I understand it, the coolant sprays a light mist on the back side of the belt, and it's not terribly messy (at least not like a surface grinder or mill), and will really help with a big metal eater like this. So, can anyone provide information on how that system worked? Pictures? Advice? I found lots of pictures of G8s online, and lots of mentions of the wet grinding system, but nothing at all about exactly how it worked or how it was constructed.

Sorry for the long post, but I just rolled it back into my shop and getting started, so lots of unknowns.

I just got it cleaned up enough and investigated the upper and lower hub lubrication. Fishing with a short piece of wire indicates that both locations appear to have common black moly grease, probably NLGI-2. So, black grease is what's in there, and assuming that's what is supposed to be in there, that's one question down.

And regarding the "wet" feature that I thought was missing.

Turns out, it doesn't work at all as I thought it did from what little information I found. I had read something to the effect that it sprays a mist of coolant on the back side of the belt. I took that to mean on the portion of the belt going up from the drive wheel to the idler (not the backing side), and there was nothing at all back there. However, while breaking out a bunch of debris the consistency of low quality concrete, the remains of old abrasive and ferrous shaving rusting into a solid clump, I noticed a pipe under the work support table. It joins with a pipe plug on the left side under the table. The pipe has perhaps 20 or so small holes, clearly this is the mister spraying the belt just after it exists the work area. So, that question is solved.

However, I'm still not sure how the excess is handled. Other than the debris collection area at the bottom, which appears to only shunk debris to a 6" pipe connector for an evacuation system, there is nothing down there to form a "sump". I assume that indicates that the mist is fine enough and volume of coolant low enough that it will be handled by the debris evacuation mechanism. I suppose a total loss system makes sense for a grinder, no need for filters and such, but I had expected a more complete system. This one could be duplicated for very little effort or money on most any grinder with a suitable shroud to prevent flinging the coolant. Maybe there is some other collection mechanism I haven't uncovered yet.

In any case, at least the next person who searches the web for information no a Porter Cable G8 will find more than I did...

I believe your grinder was also made under the "Engleburg" branding, there might be information under that branding.

Cheers
Kent

Thanks. But unfortunately, it hasn't yielded a manual.

From the results I found, looks like they have smaller grinders that are perhaps the same as the Porter Cable. However, the only Engelberg I found comparable to the G8 is quite a bit different with more industrial looking angles and less art-deco curves. It looked most like the later G8s with the feed table. In any case, that's a name I didn't know, and may yet provide something useful.

Probably not too unlike their 6 x 80 that I had at one time. Gusher pump in the base that drizzled coolant at the top of the belt. Underneath the table it vigorously pressure washed the belt just prior to a scraper that stood off he surface of the belt by a whisper diverted the fluid down to a settling tank. I don't recall what the discharge size was but I am guessing 6-8 inches.

Clearly from a pre OSHA time as it put quite a bit of mist in the air.

Bearings were off she shelf, single shield, original grease who knows. Pretty sure I had Mobil EP-1 poly-urea, which in the day was the usual SKF factory fill for electric motor bearings.

Great information, thanks.

Yeah, I saw very close similarity in the small to medium grinders such as the G4/C4 C3 etc. Engelberg even makes a light duty that looks exactly like my little light duty Porter Cable CN2 (adjustable, max size: 2 x 48).

Thanks for the information on the coolant system. The only thing mine seems to have is a sort of mister bar under the table. I wonder if similar could be cheaply made with evap cooling mister nozzles, which are designed to produce a reasonably fine mist. Maybe nothing but straight water with an anti-rust additive? I suspect the one that exists in mine shoots a dozen or so tiny streams onto the belt. If I'm correct, without the wiper you described, it seems likely to be a big mess maker.

I've also noticed that the later upgrade models (including large Engelbergs), typically with the fancy tables, have the entire main casting sitting in a well, sort of like the catch basin used with Bridgeport style turret mills. So, my current theory is that it was a total loss system, and that excess coolant was probably caught in a basin where it separated, and I suppose perhaps could be filtered for reuse afterward?

With a bit of time to kill (for a change), I was reading through some of the sales brochures I found and downloaded.

Looks like it came from the factory with optional wet OR dry configuration. Wet configuration had a different casting at the lower left side from perspective of the operator. For wet operation, it seals the bottom and has a faucet and fittings supporting wet operation. The plate is removable for cleaning. And there are 2 coolant sources fed from that manifold, one under the table, and a second direct flow from the top of the work area/platten. When equipped for dry work, that lower access panel is replaced with the 6" port for the debris evacuation system. And apparently, they have that under table tube in place even when equipped for dry work. In reading, it sounded like that lower panel bolts into place, but rechecking to see if I missed anything, it looks to have been added in a non-removable manner (assume welded, but haven't checked). So, that does explain a few things.

I still hold out hope for an owner/operator manual, but I think all my questions are answered.