40 Merc block sleeved from the factory?

F1 Flathead

F1 Flathead

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Guys,
My 40 Merc block, stamped "99" on the front right corner of the intake mounting surface, had standard bore steel sleeves pressed in. Could it have come like that from the factory? They are now scuffed so I am wondering what my options are: 1) Have it resleeved, 2) Bore the existing sleeves? Can that be done? 3) Remove the steel sleeves and have it bored to the next oversize. I remember reading that "99" blocks can be bored extra large. The sleeves appear to be quite thin, unlike cast iron sleeves. I'd appreciate any insight.
Dan
 
I know some 40/41 Fords came with the thin ("tin can") sleeves but did not know Mercury blocks had them. I just rebuilt a Ford 221. It had a couple small cracks that I had stitched so this ruled out boring oversize. Found a set of NOS tin can sleeves to install. Hard to find. The sleeves have a wall thickness of .041. .083 oversize pistons used to be available so you could pull worn sleeves, hone, and install these pistons. Again, difficult to find and not reproduced. Is the bore 3 1/16"? Pull the sleeves and have the block magnafluxed and pressure checked. John
 
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I know the 40 Ford blocks had sleeves, don't know if they are thicker.

What about a Z block, I have heard the blocks with a Z stamped behind intake surface are the ones to have?

marvin
 
F1 Flathead said:
Guys,
My 40 Merc block, stamped "99" on the front right corner of the intake mounting surface, had standard bore steel sleeves pressed in. Could it have come like that from the factory? They are now scuffed so I am wondering what my options are: 1) Have it resleeved, 2) Bore the existing sleeves? Can that be done? 3) Remove the steel sleeves and have it bored to the next oversize. I remember reading that "99" blocks can be bored extra large. The sleeves appear to be quite thin, unlike cast iron sleeves. I'd appreciate any insight.
Dan
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Dan, Some 99 Merc blocks came from the factory with the steel tin can sleeves. They are to thin to be bored, your choice is to remove them, and bore the block, itself, or replace the sleeves with NOS parts. The 3 3/16 tin can sleeves are kind of hard to find, the merc 99 block can be bored to 3 5/16, even 3 3/8 with no problem.....Ed
 
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34fivewindow said:
Dan, Some 99 Merc blocks came from the factory with the steel tin can sleeves. They are to thin to be bored, your choice is to remove them, and bore the block, itself, or replace the sleeves with NOS parts. The 3 3/16 tin can sleeves are kind of had to find, the merc 99 block can be bored to 3 5/16, even 3 3/8 with no problem.....Ed
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Thanks Ed! Kinda sounds like the thing to do is pull the sleeves and bore it oversize. That will work well with my car being a hotrod and all. For now, I will continue to run it as is. It's suprising that I have little or no smoking or oil useage for the amount of scuff I see in the bottom of the bores. I'm just not sure when the scuff occured. It could have been during my last overheat prior to me tearing it down. If that's the case, I may see the smoke and oil consumption now.
Dan
 
did you mike the bore for out of round & taper if with in limits leave them . just hone them so rings seat . i don,t know why guys spend a fortune on rebuilding an eng that they will hardley drive if you plan on driving it for thousands of miles that different .years ago we would rebuild them in the car with cyl taper i just did my forty whith the tin sleves same used pistons rings i got on ebay for 10.00 it runs like a clock & i will be long gone before it gives troulbe.
 
One of the oletimers locally told me that he would pull the sleeves clean up the bore and use Ford tractor pistons? Don't know if this works?
 
The 99 series block usually cones with the "tin" sleeves. Most rebuilders in the past pulled the sleeves and installed ..083" oversize pistons. These are getting hard to find now, but the least expensive way to solve this problem is to bore ir another 40 thou and install 3 5/16 pistons, done a bunch of em. This gives 258 ci, use the 81A head and have 7.5CR. One strong mother of a Flathead.
 
richard crow said:
did you mike the bore for out of round & taper if with in limits leave them . just hone them so rings seat . i don,t know why guys spend a fortune on rebuilding an eng that they will hardley drive if you plan on driving it for thousands of miles that different .years ago we would rebuild them in the car with cyl taper i just did my forty whith the tin sleves same used pistons rings i got on ebay for 10.00 it runs like a clock & i will be long gone before it gives troulbe.
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Richard,
I like your approach. I may just do that. On my last flathead, the bores were totally shot so I had it bored to fit a set of good used pistons that a guy gave me. The guy at the machine shop thought I was nuts but hey, pistons are expensive! I'll see if these tin bores will still work and then look at Ol Ron's approach next if the bores won't clean up enough for new rings to seal. For now, I'm just going to button it back up. It's killing me to have this thing down during the best of the summer driving weather.
Dan
 
Krylon32 said:
One of the oletimers locally told me that he would pull the sleeves clean up the bore and use Ford tractor pistons? Don't know if this works?
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The tractor pistons (2N, 8N & 9N) are identical to the 239 cu. in. V8 (3 3/16" bore). They use the same .083" over pistons if you just want to remove the sleeves but watch out for prior reuilds. One I did years ago had been resleeved before and had chisel marks down the cylinder where the old sleeves had been cut out. Just ran the hone a little extra and put it together. 35+ years later it's still going.
 
I thought all Merc engines were 3-3/16 if so remove the sleeves and bore it to 3-5/16. You cani't bore the the sleeves , but I knew a guys that had his honed .030 in a Sunnen CK-10 cyl hone. Walt
 
I have several sets of NOS 3-3/16 "tin" sleeves ---more than I need for my use.

The original Ford sleeves are case hardened, and pre honed, they were designed to be replaced in the average dealer shop as part of an "in chassis" overhaul.
 
Kurt, I would be interested in a set of sleeves if you have enough. I have a low mileage '39 Merc sleever and would like to have a set in hand...by the way, I too am in NJ (Madison area) and have the toolkit from KRW for installing the sleeves. I would be happy to lend it or help install sleeves for any V8er, but will not mail it because I cannot replace it if it disappears in transit.
 
Bruce,
What does the KRW kit look like? Is it something I could make? I'm in Michigan so it's too far for me to come and borrow but I sure appreciate the offer. I've read about peeling the original tin can sleeves out and pressing in the new ones. I'm thinking you have to be darn careful not to buckle them, given how thin they are.
Dan
 
They usually go in pretty easy. I have put in many when I worked for a Ford Tractor dealer in the 60's.
 
Since the sleeves are thin, the drivers need to be full sized to support the walls...basically, each is a slug of steel that entirely fills the sleeve, with a ledge at the top. I haven't looked in the box for a while, but the force is applied by a big screw through the middle that hooks around crank.
If making one...I think probably the mandrels could be hardwood made to a push fit with a steel plate on the top...
 
Bruce Lancaster said:
Since the sleeves are thin, the drivers need to be full sized to support the walls...basically, each is a slug of steel that entirely fills the sleeve, with a ledge at the top. I haven't looked in the box for a while, but the force is applied by a big screw through the middle that hooks around crank.
If making one...I think probably the mandrels could be hardwood made to a push fit with a steel plate on the top...
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Bruce,
That's what I'm thinking. I have a wood lathe but not a metal one. I could make a big, hardwood mandrel with a flat steel plate on top and hammer or pull the sleeve in as you described. Sounds like just my speed. No machine work. Thanks.
 
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