Finally got around to changing the oil and it was a breeze.There being no oil filter made it so much easier and much less messy.The business coupe sits up high enough where I was able to lay on my back and wiggle under it and remove the drain plug. While waiting for the oil to drain,I cleaned the plug and two brass washers and after waiting for about an hour I reinstalled the plug and put in Fram conventional 30 weight detergent oil. The original owners manual states that the crankcase hold seven quarts but after adding a little over six, the dipstick showed full. I took it out for a short spin and rechecked the stick and it was still up to the full line.
Great to see clean oil in the engine again. Since I now know how simple it is to change the oil there’s no reason to not do it more often.

I’ve decided to go with Fram conventional sae 30 for now and then store it for winter. It was pretty much all that was available in quantity and seemed to fit what I needed. I plan on doing more research in the meantime and will probably have to order an oil that’s more suited to the engine’s specific needs.
Thanks!

Not sure about previous oil used or existing type in it but it is dirty and needs to be changed.
Up until now it wasn’t driven much.
I’ve put about 400 miles on it this summer and had to add about a quart of 30 weight low detergent oil about every 100 miles or so. Don’t know about the sludge situation but as mentioned it runs great with good oil pressure on the original gauge. I’ve got the original owners manual and a 1937 shop manual and neither one mentioned an oil filter. Penngrade 1 sae 30 seems to have what needs.
Any thoughts?
Thanks

Jeez!
Omit the e in coupe and Don Rickles shows up 😂.
So much for auto-correct🙄.

Speaking of operating temperature, the 6 cyl in the coup will run hot if I let it sit and idle for more than a few minutes or even in stop and go traffic. Definitely likes to be moving and have fresh air passing through the grill and side vents in the hood. Strange though,
I pulled the plugs and they were all in good shape except for carbon build up which is evidence of low speed/low rpm driving. Cleaned em up with a wire wheel, checked and re-gaped em and they were as-good as new.

Thanks for all the advice.
I acquired the business coup back in the spring and l want to change the oil before winter storage.
We live up north. Not sure what kind of oil is currently in it but I prefer to stick with a conventional 30 weight detergent oil with zinc. The engine runs well, once warmed up, but like any engine from that era it huffs a bit of oil. I’m fortunate to be able to run a non ethanol high octane fuel in it. Shell Rotella seems to fit the bill but I’m not sure about the zinc or detergent aspect. Any thoughts?

Any recommendations for my 37 business coup?
Type of oil
Thanks!