1936 pickup changing motor to a mercury motor
 

Thinking of changing my standard 21 stud
to a mercury motor
I have heard there is a big difference in performance
Has anyone done this replaced with a mercury motor and which motor is it ?
How much difference
Thanks for your help

Re: 1936 pickup changing motor to a mercury motor
 

What year(s) Mercury are you considering? Believe the earlier Mercury blocks had a larger bore and then later a longer stroke. Nothing really magic about a Mercury vs Ford engine, you can bore out a Ford to the same size as the Mercury and/or add a 4 inch Mercury crank to a Ford engine (some years of Ford blocks are easy to modify than others).

VanPelts site provides some basic engine information:

21 Stud: http://www.vanpeltsales.com/FH_web/f...cs-85early.htm
24 Stud: http://www.vanpeltsales.com/FH_web/f...85to100mid.htm
Later Model: http://www.vanpeltsales.com/FH_web/f...0to125late.htm

I would look for at least a 24 stud engine.

Re: 1936 pickup changing motor to a mercury motor
 

The 99A was 239 but the 8CM is 255. I've seen one old 21-stud that was sleeved for 3 3/16" pistons and machined to take the 8CM crankshaft. It was a lot of work but they had a motor for a 35 ford that "looked" original and ran the whole Great American Race with no major problems. I bet it cost a fortune though.

If I was going to try and use the 8CM motor in a 36, I'd change all the frontal components over to the early style frontal accessories so that I could use a generator fan. That would be less work but it would require special build up of the engine to include an early type cam so the cam gear thrust would be correct for a crab type distributor. it's still a fair amount of work but mostly bolt on. The late to early motor adapters would have to be used to fit the engine mounts. I think Bob Drake still carries those. The 49 through early 51 Merc flywheel and clutch will work with the early 3-speed transmissions.

Re: 1936 pickup changing motor to a mercury motor
 

The late to early motor adapters would have to be used to fit the engine mounts


Actually...no adapters required, just run the truck pumps. This pertains to 8BA series

Re: 1936 pickup changing motor to a mercury motor
 

Westie...nothing wrong with a 21 stud.

Re: 1936 pickup changing motor to a mercury motor
 

As to any increase in performance, the engine originally in the vehicle was rated from the factory at 85 HP. If you were to install a '52-'53 Mercury engine (rated from the factory at 125 HP) you would have almost a 50% increase in power. Other Mercury engines through the years were rated at 95, 100, and 110 HP.

Re: 1936 pickup changing motor to a mercury motor
 

I have a 36 pickup with a late merc engine. I purchased it this way & had been sitting in barn for 36 years before I purchased it a few years ago. I have not worked on it yet. Will try to get some pics of engine tomorrow. Cheers
Tony

Re: 1936 pickup changing motor to a mercury motor
 

Westie, ANY flathead you build/buy/ fit into your truck will cost $$$$. There's an old saying that with flatheads you'll never spend so much money to go so slow! Sure, you can fit a much larger displacement engine, but then how are your brakes going to handle?
I've got a 35 sedan, had the old thing forever. It is my testbed...Had numerous different engine combo's in it over the years, ranging from 221 to 284. I much prefer the smaller displacement engines in an early Ford...the general opinion, the info you'll gather from the internet, is that 221's are rubbish, the later engines are far superior, there's no substitute for cubic inches, etc.
Try this concept; change out your existing 4.11 ratio diff to a 3.78.
Throw away your nice white wall cross plies, and fit a set of radials.

Fit aluminum heads.
Fit twin carb intake
You'll have a nice driving truck.
Enjoy it for what it is.

Re: 1936 pickup changing motor to a mercury motor
 

The smoothest engine we have used in the 33 was the stock 33 babbit engine ,would pull 75 mph up a hill .
Lawrie

Re: 1936 pickup changing motor to a mercury motor
 

8RT pumps won't work as well in tight confines so I recommended 37 to 48 pumps with single belt to give more frontal room and fit the old style generator fan better. This is when you need the adapters from Drake.
https://www.bobdrake.com/FordItem.as...5-f427c44eff61

Other things will work too but this is the easiest for bolt on parts. Removing the front pulley from a 42 through 48 crank pulley would be the only mod that would require machining. The crank snout can also be shortened to fit the early short snout pulley too. The 8RT pulley is pretty big.

Re: 1936 pickup changing motor to a mercury motor
 

Rotor, with respect, those adapters are for fitting later engine into 33-34 chassis. From 35 onward, the width of the mounts is the same throughout.

Re: 1936 pickup changing motor to a mercury motor
 

Plus, fan clearance is not as critical on the pick-up as it is on the car. The radiator on the truck does not lean to the rear as much as a car does. DD