Model A or B engine? Need help please.

ShoeboxSean

New member
Hello everyone, I have recently bought a 1930 Model A sedan. My first A and I am going to be doing as much on my own as I can. I'm learning as I go and have been pretty excited about it all. I had started working on the cooling aspect of the car. While I have been doing this I kept noticing different things about the engine. Keep in mind at first I thought it was an A with a B head on it. Last week putting the new crank pulley on I found out that the timing gear cover is a B as well. Last night a local guy stopped by the garage. He has been working on his A's for a long time. I was telling him about what I knew and found out. He walked around looking at the engine and got all excited when he saw a cover where a fuel pump would go for a B. I had wondered what that was but being my research revolved around A I had only wondered what it was and why that would be there, then continued on with what I was doing at the time.

So now I'm all excited that what I have could be a B engine. I went online and found the site that lists serial numbers and dates. Here is where I get confused and I need help. The serial number is where the A engine would have it and not where the B would be. Also it seems to be a low number. If going on that alone it would be a 1928 motor but the prefix and lack of a star before and after has me wondering what it is and when. FLA 18606 is what is stamped on my block. The FL does not match the stamping of the A18606. Different font and not straight. Any ideas? I'm attaching a few pics. You can see the B head, B timing cover and the fuel pump cover. It's and A exhaust and distributor.
Thanks for any input.
 

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ShoeboxSean,

You definitely have a Model B Block and Head, and the addition of the B Front Motor Mount.
Looks like the earlier '32 with the non-counterweight crankshaft.

Model B engine Serial Number pad or boss were never stamped from the Factory, as in 1932 the Number was stamped onto the Flywheel housing and Frame.

Anything stamped onto a B block would be post production, such as rebuild or previous owner.

Darryl in Fairbanks
 
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Thank you very much! Thats awesome. I didn't notice any number on the housing. I had read it would be above the starter area but have not seen anything. Either way its a great thing, thanks again.
 
Model B Flywheel housings where much different than Model A. Model B Housing cast part is only the upper portion, with the lower cover being an extension of the Oil Pan. when you look at the back of the oil pan you will see evidence that the extension part has been removed or cut off.
The B housing also has a boss for the number.

Yours likely has the Model A Housing, which is one piece, from top to bottom.

Darryl
 
Also note that someone installed a special small crank pulley. That's fine as long as it charges and cools OK, which it likely will do. I would get rid of the fuel line with all the hoses and use an original style steel line.
 
Thanks Darrly, I didn't know that there was that much of a change from the A to B flywheel housing. I will take a look at that for sure.

Tom, the pulley you see on there is the one I have just installed. I had the radiator fixed until I can buy a new one. I changed the water pump to leak less and added a smaller pulley. right now there is an 6v alternator on there. A friend of mine has a 59ab generator he is giving me and I will have it converted to 12v.
 

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The Model B engine is far superior to the Model A engine, so you have a great engine in your Model A. I run Model B engines in both of my Model A's, and I have thousands of miles of experience doing so.

It's been my experience that the Model A water pump is better than the Model B pump, and the A pump is easier to get parts for. You can make your Model B engine look like a Model A engine by running a Model A cylinder head with a Model A water pump and Model A distributor. Changing the head enables you to get a new one with a 5.5:1 or 6:1 compression ratio.

The Model B engine has a pressurized oil feed to the main bearings. Also the connecting rod and main bearings in the Model B engine are larger than those in the Model A. Using synthetic motor oil, I regularly cruise on the interstates at 55 to 60 mph and have done so for over 40,000 miles without any bearing issues.
 
He would have to change the front timing cover since his is the Model B cover and timing would be different with the A distributor.
 
Jim,
I know that each engine may be different, but I run the Model B timing cover which gives 9.5 degrees more advance than the Model A cover. I find that the sweet spot for timing my Model B engine is about midway between the Model A and Model B timing marks. However, I agree with you, the Model A distributor should be run with the Model A timing to avoid improper timing by those who go by the book.
 
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