What did you do today?

[Blue Chips 837]

I did some more work on the full-flow oil filtration conversion on my Dodge M37's engine. I decided to slightly revise the external filter plumbing---just some minor adjustments to get a better fit.

 

(BTW, just as an explanatory note, the way the original bypass filtration worked in the old MoPar flathead six in my Dodge M37, only a small percentage of the oil was diverted through the filter; the bulk of the oil was delivered to the bearings, etc., with no filtration whatsoever. Eventually, all of the oil would pass through the filter, but if there was any dirt/debris in the oil, it would typically loop through the system many times before it all got filtered out. The later versions of this engine went to a full-flow system, so that all of the oil is filtered before it reaches the bearings. The original bypass filter media was very fine and could trap very small particles, but I think that a modern spin-on oil filter in a full-flow system should do a very adequate job of filtering, while eliminating the possibility of major damage/wear from any larger particles.)

 

First, I bored the NPT end of a male 1/4" NPT-to-JIC AN-8 adapter so that the NPT end has the same ID as the JIC end of the adapter, and also matches the standard (almost 3/8") ID of the 1/4" schedule 40 pipe. This will still allow me to maintain that full inside diameter all the way from the oil pump to the filter and back.

 

 

I turned down part of the hex area of a 1/4" female NPT-to-JIC AN-8 adapter to provide more clearance from an adjacent adapter:

 

 

The net effect of the adapter changes will be to lower everything just enough to allow me to pull the valve compartment cover straight out, without having to maneuver it over the tubing, and it will also move the tubing a little farther away from the exhaust manifold. Here's a loose/dry fit-up just to get a general idea of how the fittings should work with each other:

 

 

I'm about halfway through reassembling the transmission, which I'm totally rebuilding, but I'm waiting for a snap ring to arrive. It can be a little frustrating to get hung up by such a seemingly minor part, but the groove width and diameter are kind of unusual, so 'standard' inch sizes wouldn't work properly. I finally found a metric heavy-duty retaining ring that should be a good fit, both in terms of diameter and thickness.

 

I'm also still in the process of making a couple of upgrades to the engine valves and connecting rods, beyond what the machine shop did for me. More on that later.

 

 

Edited 3 hours ago by Blue Chips