Mercury Flatheads

Merc Cruzer said:
Take it all apart and save the parts. Put them on the shelf. Anyone that has worked on engines has a collection. Or give then to your local V8 club and they can use them for a hard luck trophy for the next show! My self I would keep them, when you finish it will remind you how far you have come in your education of a flathead.
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I've got a shed full of those parts, I must be close to being at least a Sophomore at Flathead University. :)
 
I have read that the clean out plugs of both sizes are found in both cranks.(apparently very rare to find the small plug in the merc crank)
The most obvious way to id the crank in this motor is by the merc conrods which are shorter than 7.000" centered length of the std Ford 3 3/4" rods. (someone please confirm this)
The piston heights are shorter as well( that's the height from the gudgeon center to the top edge.
That's the worst blow up inside, that I have seen in a flattie, but I'm sure that it's tame compared to some. A bit of bad luck. Better luck next time around.

THIS POST CONTAINS WRONG INFO. SEE OL' RON'S POST BELOW
 
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The rods in the American Ford made rods are the same length and part No. only the French 255 blocks have short rods. The difference is in the pistons for the Merc engines. As for the clean out plugs, yes some of the Canadian 4" cranks have the small cleanout plug. Pretty rare.
 
"But the face is pretty rusty. Is there plenty of material that can be taken off the face? May need as much as .050" to clean up good.""

I had the flywheel on my truck refaced (0.050), drilled for a 10 " clutch and balanced the clutch and flywheel as a unit. There's plenty of meat in that flywheel to do what you want.
 
I'm a learner.
Thanks for that important bit of info Ron. I didn't know.
Are the std 3 3/4 stroke pistons the right piston height for the French rods, when using the Merc crank?
 
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I can tell I came to the right place for flatheadonoism. :D
I'll clean up the block and crank a bit and do some checking.
Maybe I got the rare 4" little hole crank.
Not likely, but I'll check it out. And see if its bent too.
Thanks guys.
 
The French 63/4 rods have no business in any flathead. They are too short for proper rod angles ratio. Just buy pistons for the stroke your going to use. I get mine from EggE.
 
Judging by the crack in the one pic, yeah, that one's a goner.

Just save anything still serviceable and move on to the next one. Keep all the ford bolts and any fasteners, they're made of good material. Didn't you say there were two motors?

Mart.
 
Yeah, I have another whole long block.
I was just hoping to have a 4" crank in the Merc motor.
And, I still haven't done a proper measurement. I'll do that in a little while.
 
After doing some measuring, I think I DO have a 4" crank and pistons.
The (Ford) block may need bored again. I'll have to mic up and down the bores to see. It's already at .040". I may go on out to 3 5/16 since I'll need pistons anyway.
The busted Merc was 3.187 bore. The crank rod journals were about 2.135.
That's a quick check with calipers. All the journals look really clean except that #1. I think what may have happened is it spun then stacked the bearing. And that popped the rod bolt. Then BOOM!
I can imagine there was smoke and steam pouring out from the hood of that old school bus. Probably stopped it dead in its tracks.
 
See if you can measure across the second counter weight on the crank. Merc should be 6in. Ford 5-3/4. That pic of the plug in the crank trow isn't very good, but it looks to me about 5/8 OD of the plug. Walt
 
I did that and it measures 6 inches. So, it should be the genuine article.
Here's a better shot of the busted block.
ry%3D480


The cam was in 4 pieces!
I've been reading more about the forged steel con rods in these engines and how they will bend before breaking.
The shot above that I posted the other day showing the rod proved that.
Here is a shot of one of the pistons.
ry%3D480
Does this jibe with Mercury piston measurements?
Not that I'll use these anyway, so I guess it doesn't matter.
 
So from your picture, the piston height is about 1 1/2" or slightly less.
That will I.D. the crank.

Good pictures Jef.
 
Ol' Ron said:
The rods in the American Ford made rods are the same length and part No. only the French 255 blocks have short rods. The difference is in the pistons for the Merc engines. As for the clean out plugs, yes some of the Canadian 4" cranks have the small cleanout plug. Pretty rare.
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Both of my Canadian Merc cranks have small plugs,measure the width of the throw is the only true way to know.And they both have the Bean cast on them.
 
Oh, OK. I couldn't see anything it could be holding. Must be too much gunk. LOL!
I'm going to start pressure washing the block and other parts this weekend.
The Ford block must have lived on a dirt or gravel road. It's 1/2 inch thick in places on the outside.
I'll get the sludge plugs out of the Merc crank and blast it too.
Once I pick out all the parts I'll use, I'll take it all down and get it tanked.
Seems the Ford block is a truck engine. Or a truck pan at least. It's rear sump (sort of) with the threaded holes in the lower rear. The Merc has the center sump. According to this website http://www.btc-bci.com/~billben/flathead.htm Link to bellhousing ID photo 24 Left ids as a 48-53 8RT pan.
Photo 26 left shows the pan that was on my Merc motor. Says it's a 49-51 Ford car. (if someone doesn't know, put your cursor on the yellow target square with the photo number and the info pops up)
Which one to use? I was leaning toward the Merc pan. They both seem to be in equal shape. Of course, at this point, I can't really tell until I clean them up.:rolleyes:
 
49 thru 51 Mercury used the rear short sump design and most of them have the three studs welded to the bottom rear of the sump for extra support of the starter plate. The shoe box Fords and the later 52/53 Ford & Merc cars all had the center sump pan. Many of the truck pans also have the round clean out hole in the bottom of the sump but not all do. The 53 F-100 pick ups had a long sump pan like no others had.
 
Yep. It's got the clean out hole.
The other pan has no holes (that I know of at this time) on the bottom.
At least there were no bolts there to remove to get it apart.
I saw the pics of what you're talking about and I'm pretty sure the pan that was on the (what I've been calling) the Merc engine is a Ford pan.
It came out of a school bus. So there's no telling what went on back then in the DoE mechanics shop.
 
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