G'Day ,
I have just recently come across an early 4 cylinder engine that I believe is about 1921 or earlier vintage. Initially I was led to believe it was a Chevrolet, but I now believe it may be an Olds.
It has no head, but came with a 3 port exhaust manifold number 381096. I was previously in possession of a 3 port head number 381099.
I am only familiar with 4 cyl Chevy engines from about 1922 - 1928.
I can't currently locate any numbers on the block. I don't have any experience with Olds engines of this era.
What stands out to me, is the oil pan doesn't bolt straight to the block, but has a cast skirt between the two. It also has a threaded dip stick. I have never seen that before.
It has the gear driven Autlolite System M generator, and Autolite M 407 10D starter. Starter & generator both mounted on right side.
If anyone can shed some light on this it would be appreciated.
Thanks for your time, attention and anticipated enlightenment.............Joe.............

 

welcome joe

hopefully someone knows more about your engine, a few pictures may help as well.

despite the classic olds name most of the banter on here is about 50 year old engines and parts , 100 year old ones are tougher to come by

 

 

Thanks for the response. I'm still not sure what the make is other than GM, but I found the following on the block after scraping off 100 plus years of accumulated crud:
R 3950 11 5 18 2
I believe the 11 5 18 is November 5, 1918 or 11 May 1918.

 

We want you stick around here but your best bet to deciphering this engine will be on AACA Forums www.aaca.org or the H.A.M.B. www.jalopyjournal.com forums

The Oldsmobile knowledge here has no equal, but the general knowledge of all old automotive stuff there is nothing short of astounding.

Let us know what it turns out to be. What I can tell you is that Oldsmobile produced no four cylinder engines from 1917 thru 1920, but did again from 1921 thru 1923.

 

The 4 cylinder engines of that period ended in '23 on the 43A but went back as far as 1916 from memory. I may not have my facts completely correct but the OHV 8 & 6 engines were certainly made by Northway and I believe the 4 cylinder used in the Model 43, 43A & Economy Truck were Northway engines too. If the 43A engine was anything like the Olds model 30 engines (upward of '23) then you might find the engine number stamped onto a pad above the water pump. I do have a list of the engine numbers by year if you can find the number on your engine.
Regarding sources of info, if you are on FaceBook join the National Antique Oldsmobile Club page and post a few pics of the engine there. I'm sure you will get some feedback.
Cheers
Rohan

 

Thanks for the reply and information. After scraping the block down to bare metal, I located the following numbers/letters on the left side of the block just above the bottom edge of the block.
R 3950 11 5 18 2 I believe the 11 5 18 is the block date of November 5th 1918 or 11 May 1918. From later Chevrolet block codes that I am more familiar with, I suspect it is November 5th 1918. That would make it at 1919 model year I think...............Joe...................

 

This list unfortunately doesn't show an "R" prefixed number but it may not be 100% correct. This is from an Olds Master Parts List printed in '26

 

The images of the Olds Truck engine look pretty much the same as the block in question. I notice one difference being the "v" shaped formations in the skirt below the block in the truck engine depiction, are not evident on this block. I assume they would be there to stiffen the sides of the skirt. (Skirt being my description). Otherwise they could be identical.
The letter/numbers I supplied may have been confusing they way I listed them. The first letter "R" is remote from the "3950" numbers. The date code as I believe it to be is separate, and there are single spaces between 11...5...18.. The "2" is also remote.
There is no doubt with the information you have provided that this is an OLDS engine, but it would still be nice to nail it down further in the event someone out there could use the parts for restoration, repairs or spares.
Once again your assistance / research is much appreciated.............Joe........

 

You're welcome Joe. I hope you find the right person who can use it. We've got a few 43.A's here in Australia but there's more parts than complete cars. Cheers Rohan