manual doesn't help, HG OC3 differences?

ObsoElitist · May 04, 2015, 03:29:10 AM

Someone said my crawler may have HG tracks, they are not the same as in my new OC3 manual for serials 3500000 and 1W000 and up. There is no tag on the starterless bellhousing, and I have an engine that is marked as both 4 cyl gas, waterpumpless Hercules Engines. Does this show HG parts, or just 1939 Oc3, as the engine indicates?

My issues are
1, instead of having on the final drive cover an iron bearing cover with a fill plug as on page 41, there is only a stamped bump on one side and a flat surface on the other. Did they make one with no outer axle bearing, and should I find plugs on the main cast iron housing when I crawl under it?

2, I have no waterpump, is there a thermostat?

3, since the seat and gas tank block the transmission fill plug, there is a1/2 inch bolt I can access on the top rear of the differential housing in the center, pointing down. If I pull it, will something let go inside? I may just have to fill through the level plug, sure to be a very slow process.

ObsoElitist · May 04, 2015, 11:46:54 PM

Confirmed today there is a fill plug inboard of the tracks on top of the axle housing, an overfill plug and a drain plug on the same casting at the bottom. The outboard coveres are a single stamped piece. Is this how and HG is built?

Blake Malkamaki · May 05, 2015, 01:50:16 AM

No thermostat. Yours uses thermosyphon to circulate the water in the radiator. A thermostat is not necessary as it won't circulate until it's hot.

Did you look for a serial number plate on the side of the frame. Right outside of frame near where your foot rest is.

Blake

Lowspeedlife · May 05, 2015, 12:17:37 PM

According to the list of HG/OC3 "improvements" they added the final drive pinion outer bushing in 1941 serial number 5GA180. As Blake said without a water pump there is no thermostat. Oliver acquired Cletrac on October 31, 1944 and continued to call them HGs until late in the 1940's, not exactly sure when but the "Oliver Cletrac" decals started in 1944 so it would have been after then in all likelihood. It sounds like you have an HG, not an OC3 & probably an 1941 or older.

Scott R.

ObsoElitist · May 05, 2015, 04:43:52 PM

That falls in with the IXA3 engine tag, and IXB3 stamped on the deck. Zimmerman said the number was from 1939. I guess I need another manual. There is no tag on the frame, body or bell housing. Its a weird one, you saw the pictures in my ID thread a while back.
Does the HG also take 140 weight mineral oil in the gears and rollers for warm temps?
So I guess this makes it a Cletrac, and not an Oliver?
Thank you

Lowspeedlife · May 05, 2015, 08:43:11 PM

I have one that is an HG, I'm guessing from late '40 or '41. It also has no holes in the right frame rail where the tag should be or on the flywheel housing. It too is a hand crank start model without a water pump, IXA3 engine with a casting date of 2/29/40. (Yes 1940 was A leap year, I checked). As I have previously said I think it's a '41 because they normally allow cast iron to "season" about a year before machining it. The IXA3 engine would be right for an early cletrac, the IXB engines were not installed until 1950, unless the engine was replaced sometime in the past. I doubt the engine could have been bored out to 3 1/4 inches from 3 inches but I guess it could have been sleeved to 3 1/4 inch. Other than the IXB stamping it all sounds like an early HG.

Lowspeedlife · May 05, 2015, 09:21:22 PM

Yes the GL 140/50wt should be correct as the transmission/differential is the same in all HG/OC3s.

ObsoElitist · May 06, 2015, 05:37:51 PM

I ordered an HG manual last night.

ObsoElitist · May 09, 2015, 04:34:18 AM

I got an 1948 original HG manual today. I shows that the final drive pinions are a compleletly different design. Also, it says to run 60 weight oil, not 50 as many do. That is equal with 140 weight mineral oil on the viscosity conversion chart. Ill be picking up a bucket of 140 on Monday, dont know if anyone still makes 60 non detrgent.
I have all the gearboxes drained and refilled with some 3p year old 40 weight non detergent i got at and auction very cheap, along with all zerks pumped full of the same, fresh oil in the engine, fuel system clean and functional. I hope to pull start it with the truck tomorrow and spend an hour or two moving dirt to see how bad the hydraulic leaks are before taking it apart to fix the hand start system. As soon as I shut it down I wil drain all the fluids and leave them open overnight to get all the sludge out. It should be a fun morning