Technical 1951 Mercury Flathead into 1949 Ford...a few questions for those with experience

I have a completely unmolested original 1949 Ford (car) with the 100% original 8BA flathead/3-speed OD. I bought a complete, original & unmolested running 1951 Mercury flathead V8/3-speed OD combo to put in my '49 (gotta keep a flattie in there).

I understand that there are specific differences with the water pumps, bellhousing, clutch fork, etc. etc.

I have researched, read, and looked for a concise answer but have come up lacking certainty I need. Could you guys help a guy out with some clarity? I'm a flathead newb who's just cutting his teeth on this stuff. Still trying to figure out where the hell the valve covers go...

Thanks
Todd

 

If you use the Ford's transmission, clutch, bellhousing, oil pump, oil pan, & water pumps on the Merc engine, just bolt it in and drive.

 

Well, not quite as cut & dry as I had hoped, but that's the kind of info I was looking for. Thanks

 

back in the 60's, I put a 51 Merc engine and transmission in my 1953 Mainline 2-door. I switched it to the overdrive transmission too. I think the 49 ford and 51 merc have the same belllhousing also. You will be happy with the power increase, as I could beat some 265 chevys with it.

 

The '51 Merc has a different bell housing and clutch throwout mechanism than the Ford. The transmission also has some differences ('51 Merc omits the rail switch), although I don't know if the overall dimensions are the same or not.


If you have "unmolested original" Ford parts, then by all means use them. Just think of the Merc as a short block to add all your Ford accessories to. The only internal differences are the crank and the pistons.

I'd use the Merc intake (for 4 bolt carbs) and the Ford heads (greater compression).

This is probably the easiest engine swap that can be done.

 

Great...the Ford only has 76k miles, but sat for about 25 years and the engine is stuck really hard. It wasn't stored well. The transmission shifted great at that time, so not too concerned with using all that equipment.

Probably leave the heads/intake on the Merc as-is (except swap the Merc carb out) since they were running happily with regular use. I'd like to do aluminum heads and a 2x2 intake eventually, but for now just want it to be a runner again. Headers will likely be the only performance upgrade at first.

Appreciate the input, guys.

 

Early 51 Mercs had the half bellhousing like the earlier Ford Flatheads (48 and earlier) and 49 and 50 Mercs did They changed to the Bellhousing like the 8BA had in mid 51 year model.

Either way if you get the complete unit with OD Trans it should be a fairly simple swap outside of a few small issues like maybe the water pumps needing swapped for 8BA pumps and a bit of tinkering with clutch and throttle linkage. You will probably have to shorten the driveshaft to compensate for the OD trans extra length too. But nothing hard and nothing scary about that swap.

 

The Ford and Merc V8's had different clutches, thus different flywheels. Just swap the Ford flywheel and clutch, the Ford bell housing with its starter plate, onto the Merc motor and it will work for you.

 

Are we sure that the flywheel is different?

I was going to install new water pumps anyway, and it looks like after the pan/pump are swapped it should be pretty cut & dry.

It will make the process a helluva lot easier to R&R the flathead without the 3-speed hanging off the back!

Again, I appreciate the input guys. Truly

 

Up thru 1951 the Merc clutches were the Borg & Beck style, whereas the Fords used the Long style. Primary difference is the bolt pattern for the pressure plate. So even if the Ford clutch was a 10" (truck or special duty car) its bolt pattern was in three sets of 2 closely spaced holes in the flywheel. The Merc B&B clutch had a bolt pattern where all the six holes were equally spaced from each other.

To confuse matters slightly, the '49-56 Ford car trans had the 1" x 10 spline input shaft. The '49-50 Merc had the 1-3/8" x 10 spline input shaft. Early '51 Mercs still used that but mid year they changed to the 1" x 10 spline input. Different clutch bearing used for the 1" vs the 1-3/8" input.

So what does this mean for you? Assuming you're using the 49 Ford flywheel, clutch disc & pressure plate, clutch release components, transmission, you can just bolt all this up to the back of any 49-53 Merc V8 motor. As stated above, just swap your Ford oil pan, starter plate, and water pumps onto the Merc motor and you're good.

 

Awesome...thanks. Now, to figure out the best way to get the clutch ass'y off of a stuck flathead