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More on A Type The Overdrive

KVH

Obi Wan
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On my 4A, I'm a slow learner. I've rebuilt the OD again, this time to better seat the front annulus bearing. The input and output shafts now seem to spin more freely.

As Randall and a few of you may know, I'm trying to "bench" test the OD with a 1/2" drill. It sort of works, but not good enough, and my hose union between the drill and input shaft still wants to spin, partly because it appears the hose isn't tight enough--or because the resistance is still for some reason too much.

I can't believe I still a bearing not seated correctly. I wasn't very bold with the press, but I also didn't want to damage the casing and I went gradually until it stopped moving and until the force seemed heavy.

I'm inclined as shown in the various articles to buy a cheap motor and a couple of pulleys, keeping RPMs below 800.

As I wade through all this, I guess I'd better ask some more questions. First, the input shaft turns noticeably more easy in first and second gear than in fourth gear. Third gear is also easier than fourth. The "drill test" seems to work best in first gear.

Does all that seem right? Less resistance in first and second?

For some reason I'd thought that the resistance at the input shaft would be greater in first and second gear.

Second, no matter how hard I try, there's no way I'll get 4.2 pints of gear oil in the transmission. Is the shop manual wrong about the capacity. I'm getting about 3.5 pints.

I also wonder if my brand new thick and chilly GL4 gear oil is part of why I'm feeling a little more resistance than expected.

I'll do a third tear down if I need to!

Thanks all.
 
Absolutely less resistance makes sense in 1st,2nd and 3rd- thats your gear ratios at work.

If you can rig up a socket on your your drill, I run the overdrive from the output flange - no slip that way.
 
+1, on above. The resistances are entirely correct.
Cold, thick oil WILL make the gear box stiffer.
The last time I assembled/bench tested mine, I almost smoked my Milwaukee Magnum 1/2" drill. I did start to smell it. So, I stopped. But, the next day, before I stripped it down again, I tried one more time -- running it for a while in 1st gear to get things moving and then up through the gears. It worked.

I won't be all "surprised," however, when that 30-year-old drill needs to rewound.
 
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