35 or 36 flathead

robertwg

Member
Okay after having the car about 3 months now and fixing a bunch of odds and ends got around to the motor. No aluminum heads thought 35 was supposed to have aluminum heads. Wire wheeled the paint off of heads and found numbers 68-6050b and 68-6049b on top left corner of block is LB. So I guess I have a 36 motor in my 35. Is this good bad or indifferent.

Thanks Bob
 
I believe most people consider the LB one of the best 21 stud blocks, but I know very little about them. So, I would say good.
 
I can tell you that having an LB engine in your '35 would not be a bad thing. LB = Loose/Large Main Bearings. This usually translates into a lower cost rebuild as compared to a poured babbitt mains engine. Rumor has it that some LB's were used in late model year production of '35's. So, if that is true, you have an engine that could have been used in both '35 and '36. The 68-×××× pn heads are normally used with dome top pistons, although some have used flattop pistons with domed cyclinder heads, causing a reduction in compression. While aluminum heads came off the assembly lines on '35 passenger cars, many were replaced early on with cast iron, because of corrosion damage due to the affects of electrolysis occuring between two dissimilar metals in the presence of an electrolyte.
 
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Bob-

Much of what John was saying about the LB is true. It and the '37 (with block-off plates), are excellent 21 stud engines for a '35-'36. As for the "68" heads there has been much discussion on this Forum and HAMB about the origin of these heads. The collective wisdom seems to believe that the "68" was never a production head. It apparently was a Ford after-market head. Considering the age of a '35 or a '36 it undoubtedly underwent some repairs that resulted in a set of new heads.

Tom
 

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So John it's possible that I have a 35 block with 36 heads. Anyway to tell without tearing down the motor?

Bob

To answer your two questions in order, I would say absolutely, and not to my knowledge. The blocks and internals are basically identical, if you separate the poured babbitt from the insert main bearing LB. Now, there are exterior component differences, but these are "bolt ons" that can be swapped back and forth at will, and usually were. Some of these components would include; heads, water pumps, distributors, coils, intake manifolds, fuel pumps, carburetors, generator cutouts, etc.
 
Bob-

Much of what John was saying about the LB is true. It and the '37 (with block-off plates), are excellent 21 stud engines for a '35-'36. As for the "68" heads there has been much discussion on this Forum and HAMB about the origin of these heads. The collective wisdom seems to believe that the "68" was never a production head. It apparently was a Ford after-market head. Considering the age of a '35 or a '36 it undoubtedly underwent some repairs that resulted in a set of new heads.

Tom

Tom, please let me know what I may have said in my earlier post that's not true about the LB engines, since I will be the first to admit, I am still learning new things most everyday on these old Fords.
 
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I suggest you get the Early Ford V8 Club of America 35-36 restoration book. It is available on their web site. The LB block was introduced in late Oct. of 35. By the first couple of weeks of Sept. 35 production of the 35 Fords had ceased and 36 production had begun. The LB block is not correct for the 35 Ford. The 68- part number heads came out as a replacement only part in late 36. These would also be incorrect for a 35. The restoration book can also help you find an approximate production date for your 35 car.
 
I suggest you get the Early Ford V8 Club of America 35-36 restoration book. It is available on their web site. The LB block was introduced in late Oct. of 35. By the first couple of weeks of Sept. 35 production of the 35 Fords had ceased and 36 production had begun. The LB block is not correct for the 35 Ford. The 68- part number heads came out as a replacement only part in late 36. These would also be incorrect for a 35. The restoration book can also help you find an approximate production date for your 35 car.

Well, I wonder how I wound up with a documented original engine and transmission, with matching serial numbers on both transmission and frame that is late '35 and removed from a '35 pickup that had never been apart and the engine is definately an LB. Perhaps the book is wrong. It has been wrong before and probably will be again. Will post pictures of this engine later today when I return home. The present owner of this pickup can confirm this truck was original by the original owner and it had never been taken apart. This pickup now has a later engine and suspension but from the outside still looks original. The owner is a Fordbarn member and I will contact him to see if he will chime in here with more facts.
 
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